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  <xsd:element id="fdus_AverageDebtPerShare" name="AverageDebtPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AverageFullyDilutedEquityOwnershipPercentage" name="AverageFullyDilutedEquityOwnershipPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AverageNetAssets" name="AverageNetAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_BaseManagementAndIncomeIncentiveFeeWaivers" name="BaseManagementAndIncomeIncentiveFeeWaivers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_BaseManagementFeeWaiver" name="BaseManagementFeeWaiver" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_BorrowingsUnderCreditFacilityNetOfDeferredFinancingCosts" name="BorrowingsUnderCreditFacilityNetOfDeferredFinancingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_CapitalGainsIncentiveFeeAccruedReversed" name="CapitalGainsIncentiveFeeAccruedReversed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_CapitalGainsIncentiveFeePayable" name="CapitalGainsIncentiveFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_CapitalGainsIncentiveFeePayableDueToAffiliate" name="CapitalGainsIncentiveFeePayableDueToAffiliate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_CapitalLossCarryForward" name="CapitalLossCarryForward" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_CapitalLossCarryForwardUtilization" name="CapitalLossCarryForwardUtilization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_CommitmentsOutstandingToFundVariousUndrawnRevolvingLoansOtherDebtInvestmentsAndCapitalCommitments" name="CommitmentsOutstandingToFundVariousUndrawnRevolvingLoansOtherDebtInvestmentsAndCapitalCommitments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_CommonStockWeightedAveragePricePerShare" name="CommonStockWeightedAveragePricePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_CumulativeGrossProceedsFromIssuanceOfCommonStock" name="CumulativeGrossProceedsFromIssuanceOfCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_CumulativeUnderwritingFeesAndCommissionAndOfferingCosts" name="CumulativeUnderwritingFeesAndCommissionAndOfferingCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DebentureLeverageFees" name="DebentureLeverageFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_Debentures" name="Debentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_DebtInstrumentAdditionalAggregatePrincipalAmount" name="DebtInstrumentAdditionalAggregatePrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DebtInstrumentAssetCoveragePercentage" name="DebtInstrumentAssetCoveragePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentAverageMarketValuePerUnitIncreaseAmount" name="DebtInstrumentAverageMarketValuePerUnitIncreaseAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_DebtInstrumentInterestRatePercentageBasedOnAfterCertainConditionsSatisfied" name="DebtInstrumentInterestRatePercentageBasedOnAfterCertainConditionsSatisfied" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentInterestRatePercentageBasedOnPriorToCertainConditionsSatisfied" name="DebtInstrumentInterestRatePercentageBasedOnPriorToCertainConditionsSatisfied" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentInterimInterestRate" name="DebtInstrumentInterimInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentIssuedAmount" name="DebtInstrumentIssuedAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DebtInstrumentMaturityYearRangeEnd" name="DebtInstrumentMaturityYearRangeEnd" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentMaturityYearRangeStart1" name="DebtInstrumentMaturityYearRangeStart1" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentPoolingDate" name="DebtInstrumentPoolingDate" type="xbrli:dateItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtInstrumentRedemptionOfAggregatePrincipalAmount" name="DebtInstrumentRedemptionOfAggregatePrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DebtInstrumentRedemptionOfIssuedAndOutstandingAmount" name="DebtInstrumentRedemptionOfIssuedAndOutstandingAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DebtInstrumentRedemptionOfRemainingAggregatePrincipalAmount" name="DebtInstrumentRedemptionOfRemainingAggregatePrincipalAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DebtInvestmentInNumberOfPortfolioCompaniesOnNonAccrualStatus" name="DebtInvestmentInNumberOfPortfolioCompaniesOnNonAccrualStatus" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DebtIssueCosts" name="DebtIssueCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DeemedDistributionOfLongTermCapitalGains" name="DeemedDistributionOfLongTermCapitalGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DeferredFinancingCostsExcludingSecuredBorrowings" name="DeferredFinancingCostsExcludingSecuredBorrowings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_DeferredUnderwritingDiscounts" name="DeferredUnderwritingDiscounts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DeferredUpfrontFees" name="DeferredUpfrontFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_DesignateRetainedNetCapitalGains" name="DesignateRetainedNetCapitalGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_DesignateRetainedNetCapitalGainsPerShare" name="DesignateRetainedNetCapitalGainsPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DistributionsToCommonStockholders" name="DistributionsToCommonStockholders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_ExpensesNetOfBaseManagementAndIncomeIncentiveFeeWaivers" name="ExpensesNetOfBaseManagementAndIncomeIncentiveFeeWaivers" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_FairValueAssetsLevelOneToLevelTwoTransfersAmount" name="FairValueAssetsLevelOneToLevelTwoTransfersAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_FairValueAssetsLevelTwoToLevelOneTransfersAmount" name="FairValueAssetsLevelTwoToLevelOneTransfersAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAccretionOfLoanOriginationFees" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAccretionOfLoanOriginationFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAccretionOfOriginalIssueDiscount" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetAccretionOfOriginalIssueDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetInterestAndDividendIncomePaidInKind" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetInterestAndDividendIncomePaidInKind" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetProceedsFromLoanOriginationFees" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetProceedsFromLoanOriginationFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_FairValueOfLoansIncludedInInvestments" name="FairValueOfLoansIncludedInInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_GrossProceedsFromIssuanceOfCommonStockUnderAtTheMarketProgram" name="GrossProceedsFromIssuanceOfCommonStockUnderAtTheMarketProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncentiveFeeReversalCapitalGains" name="IncentiveFeeReversalCapitalGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncomeIncentiveFee" name="IncomeIncentiveFee" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncomeIncentiveFeePayable" name="IncomeIncentiveFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_IncomeIncentiveFeesPayableDueToAffiliate" name="IncomeIncentiveFeesPayableDueToAffiliate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_IncomeIncentiveFeeWaiver" name="IncomeIncentiveFeeWaiver" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncomeTaxProvisionBenefitFromRealizedGainsOnInvestments" name="IncomeTaxProvisionBenefitFromRealizedGainsOnInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncomeTaxProvisionFromDeemedDistributionOfLongTermCapitalGains" name="IncomeTaxProvisionFromDeemedDistributionOfLongTermCapitalGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncreaseDecreaseAdditionalPaidInCapital" name="IncreaseDecreaseAdditionalPaidInCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_IncreaseDecreaseAdministrationFeePayableAndOtherDueToAffiliate" name="IncreaseDecreaseAdministrationFeePayableAndOtherDueToAffiliate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncreaseDecreaseInAccruedInterestAndFeesPayable" name="IncreaseDecreaseInAccruedInterestAndFeesPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncreaseDecreaseInBaseManagementFeePayable" name="IncreaseDecreaseInBaseManagementFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncreaseDecreaseInCapitalGainsIncentiveFeeReversalDueToFromAffiliate" name="IncreaseDecreaseInCapitalGainsIncentiveFeeReversalDueToFromAffiliate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_IncreaseDecreaseInIncomeIncentiveFeePayableDueToAffiliate" name="IncreaseDecreaseInIncomeIncentiveFeePayableDueToAffiliate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_IncreaseDecreaseInTotalDistributableEarnings" name="IncreaseDecreaseInTotalDistributableEarnings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_InterestAndDividendIncomePaidInKind" name="InterestAndDividendIncomePaidInKind" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_InterestEarningOnUnfundedBalanceCommitment" name="InterestEarningOnUnfundedBalanceCommitment" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InterestOnIdleFunds" name="InterestOnIdleFunds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_InvestmentAndMoneyMarketFundsOwnedPercentOfNetAssets" name="InvestmentAndMoneyMarketFundsOwnedPercentOfNetAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyAssetCoveragePerShare" name="InvestmentCompanyAssetCoveragePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyBaseManagementFeeWaiver" name="InvestmentCompanyBaseManagementFeeWaiver" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyDistributionsFromCapitalGainsPerShare" name="InvestmentCompanyDistributionsFromCapitalGainsPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyDividendsToStockholdersPerShare" name="InvestmentCompanyDividendsToStockholdersPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyExpenseRatioToAverageNetAssets" name="InvestmentCompanyExpenseRatioToAverageNetAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyExpensesRatioBeforeBaseManagementFeeWaiver" name="InvestmentCompanyExpensesRatioBeforeBaseManagementFeeWaiver" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyInvestmentIncomeLossPeriodIncreaseDecrease" name="InvestmentCompanyInvestmentIncomeLossPeriodIncreaseDecrease" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyPercentageOfIncentiveFeeWaived" name="InvestmentCompanyPercentageOfIncentiveFeeWaived" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyPortfolioTurnoverRatio" name="InvestmentCompanyPortfolioTurnoverRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentCompanyTotalReturnBasedOnMarketValue" name="InvestmentCompanyTotalReturnBasedOnMarketValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentIncomeExpenseNetAfterTax" name="InvestmentIncomeExpenseNetAfterTax" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_InvestmentIncomeFeeIncome" name="InvestmentIncomeFeeIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_InvestmentIncomePaymentInKindInterestIncome" name="InvestmentIncomePaymentInKindInterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_InvestmentMaturityPeriod" name="InvestmentMaturityPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentOwnedAtCostNetOfClosingFeeAllocation" name="InvestmentOwnedAtCostNetOfClosingFeeAllocation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_InvestmentsAndMoneyMarketFundsOwnedAtCost" name="InvestmentsAndMoneyMarketFundsOwnedAtCost" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_InvestmentsAndMoneyMarketFundsOwnedAtFairValue" name="InvestmentsAndMoneyMarketFundsOwnedAtFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_InvestmentsAsPercentageOfAssets" name="InvestmentsAsPercentageOfAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_LineOfCreditFacilityMinimumUtilizationCommitmentFeePercentage" name="LineOfCreditFacilityMinimumUtilizationCommitmentFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_LineOfCreditFacilityRemainingUnusedCapacityCommitmentFeePercentage" name="LineOfCreditFacilityRemainingUnusedCapacityCommitmentFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_LongTermCapitalGain" name="LongTermCapitalGain" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_ManagementFeesAnnualRatePercentage" name="ManagementFeesAnnualRatePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_MaximumAggregateOfferingPriceOfCommonStockUnderAtTheMarketProgram" name="MaximumAggregateOfferingPriceOfCommonStockUnderAtTheMarketProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_MoneyMarketFundsAtFairValue" name="MoneyMarketFundsAtFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_MoneyMarketFundsOwnedPercentOfNetAssets" name="MoneyMarketFundsOwnedPercentOfNetAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NetAssetValuePerShareOther" name="NetAssetValuePerShareOther" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NetChangeInUnrealizedAppreciationDepreciationOnInvestments" name="NetChangeInUnrealizedAppreciationDepreciationOnInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_NetIncreaseDecreaseInNetAssetsResultingFromOperationsToCommonStockholdersBasicAndDiluted" name="NetIncreaseDecreaseInNetAssetsResultingFromOperationsToCommonStockholdersBasicAndDiluted" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NetRealizedGainLossOnInvestmentsNetOfTaxes" name="NetRealizedGainLossOnInvestmentsNetOfTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_NetUnrealizedAppreciationDepreciationOnInvestments" name="NetUnrealizedAppreciationDepreciationOnInvestments" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NumberOfInvestmentPorfolioCompanies" name="NumberOfInvestmentPorfolioCompanies" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NumberOfInvestmentsRepresentedMoreThanTenPercentageOfAggregateInvestmentPortfolio" name="NumberOfInvestmentsRepresentedMoreThanTenPercentageOfAggregateInvestmentPortfolio" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NumberOfResidualInvestmentPorfolioCompanies" name="NumberOfResidualInvestmentPorfolioCompanies" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_OrdinaryIncomeDistributions" name="OrdinaryIncomeDistributions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_OutstandingSbaDebentures" name="OutstandingSbaDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_OwnershipPercentageOfOutstandingVotingSecuritiesInPortfolioInvestment" name="OwnershipPercentageOfOutstandingVotingSecuritiesInPortfolioInvestment" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PaidInKindInterestIncome" name="PaidInKindInterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_PaymentPercentageOfPreincentiveFeesNetInvestmentIncome" name="PaymentPercentageOfPreincentiveFeesNetInvestmentIncome" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PaymentsOfDividendsIncludingExpenses" name="PaymentsOfDividendsIncludingExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_PercentageOfAmountOfPreIncentiveFeeNetInvestmentIncome" name="PercentageOfAmountOfPreIncentiveFeeNetInvestmentIncome" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfBoardRepresentation" name="PercentageOfBoardRepresentation" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfCapitalGainsIncentiveFeeAccrued" name="PercentageOfCapitalGainsIncentiveFeeAccrued" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_Percentageofcost" name="Percentageofcost" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfEquityInvestmentsHeldInPortfolioCompanies" name="PercentageOfEquityInvestmentsHeldInPortfolioCompanies" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfExciseTax" name="PercentageOfExciseTax" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_Percentageoffairvalue" name="Percentageoffairvalue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfInvestmentCompanyTaxableIncome" name="PercentageOfInvestmentCompanyTaxableIncome" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfMinimumQualifyingAssetsToPurchaseNonQualifyingAssets" name="PercentageOfMinimumQualifyingAssetsToPurchaseNonQualifyingAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfNetCapitalGains" name="PercentageOfNetCapitalGains" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfNetCapitalGainsRealized" name="PercentageOfNetCapitalGainsRealized" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfNonQualifyingAssetsFairValue" name="PercentageOfNonQualifyingAssetsFairValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfPortfolioInvestmentsAtFairValue" name="PercentageOfPortfolioInvestmentsAtFairValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfPublicOfferingPrice" name="PercentageOfPublicOfferingPrice" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfTaxableIncome" name="PercentageOfTaxableIncome" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PercentageOfVotingSecurities" name="PercentageOfVotingSecurities" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PermanentBookIncomeAndTaxIncomeDifferences" name="PermanentBookIncomeAndTaxIncomeDifferences" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_PreIncentiveFeeFixedHurdleRate" name="PreIncentiveFeeFixedHurdleRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PrepaymentOfDebentures" name="PrepaymentOfDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_ProceedsFromSalesAndRepaymentsIncludingPrincipalReturnOfCapitalDistributionsAndRealizedGains" name="ProceedsFromSalesAndRepaymentsIncludingPrincipalReturnOfCapitalDistributionsAndRealizedGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_ProceedsFromSalesAndRepaymentsOfInvestments" name="ProceedsFromSalesAndRepaymentsOfInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_ProceedsReceivedFromRepaymentsOfSecuredBorrowingsNet" name="ProceedsReceivedFromRepaymentsOfSecuredBorrowingsNet" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_ProceedsReceivedFromSmallBusinessAdministrationDebentures" name="ProceedsReceivedFromSmallBusinessAdministrationDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_RealizedInvestmentGainsLossesOnEscrowSecuritiesNotHeldDuringPeriod" name="RealizedInvestmentGainsLossesOnEscrowSecuritiesNotHeldDuringPeriod" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_RepaymentsOfSmallBusinessAdministrationDebentures" name="RepaymentsOfSmallBusinessAdministrationDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_SalesAgentCommissionsAndOfferingCostsUnderAtTheMarketProgram" name="SalesAgentCommissionsAndOfferingCostsUnderAtTheMarketProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_SbicDebentureProgramMaximumAmountOutstandingSbaDebentures" name="SbicDebentureProgramMaximumAmountOutstandingSbaDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_SecuredBorrowings" name="SecuredBorrowings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_SeniorAssetCoverageRatio" name="SeniorAssetCoverageRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SeniorSecuritiesAmountOutstandingExcludingTreasurySecurities" name="SeniorSecuritiesAmountOutstandingExcludingTreasurySecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_SeniorSecurityIndebtednessThresholdAssetCoverageRatioPerUnit" name="SeniorSecurityIndebtednessThresholdAssetCoverageRatioPerUnit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_SeniorSecurityIndebtednessThresholdPerAverageMarketValuePerUnit" name="SeniorSecurityIndebtednessThresholdPerAverageMarketValuePerUnit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_ShareValueAvailableUnderAtTheMarketProgram" name="ShareValueAvailableUnderAtTheMarketProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_TaxableIncome" name="TaxableIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_TaxableIncomeEarnedInCurrentPeriodAndCarriedForwardForDistributionInFollowingYear" name="TaxableIncomeEarnedInCurrentPeriodAndCarriedForwardForDistributionInFollowingYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_TaxableIncomeEarnedInPriorYearAndCarriedForwardForDistributionInCurrentYear" name="TaxableIncomeEarnedInPriorYearAndCarriedForwardForDistributionInCurrentYear" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_TaxableSubsidiariesLiquidatingDistributions" name="TaxableSubsidiariesLiquidatingDistributions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_TaxBasisAmortizedCostOfInvestments" name="TaxBasisAmortizedCostOfInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_TemporaryBookIncomeAndTaxIncomeDifferences" name="TemporaryBookIncomeAndTaxIncomeDifferences" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_TemporaryBookTaxDifferences" name="TemporaryBookTaxDifferences" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_TotalDistribution" name="TotalDistribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_UnderwritingDiscounts" name="UnderwritingDiscounts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_UndistributedLongTermCapitalGains" name="UndistributedLongTermCapitalGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_UndistributedLongTermCapitalGainsPerShare" name="UndistributedLongTermCapitalGainsPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_UndistributedOrdinaryIncome" name="UndistributedOrdinaryIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_UndistributedOrdinaryTaxableIncomePerShare" name="UndistributedOrdinaryTaxableIncomePerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_UnitedStatesFederalIncomeTaxesBehalfOfStockholdersRelatedDeemedDistribution" name="UnitedStatesFederalIncomeTaxesBehalfOfStockholdersRelatedDeemedDistribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_UnitedStatesFederalIncomeTaxesBehalfOfStockholdersRelatedDeemedDistributionPerShare" name="UnitedStatesFederalIncomeTaxesBehalfOfStockholdersRelatedDeemedDistributionPerShare" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_UnrealizedAppreciationDepreciation" name="UnrealizedAppreciationDepreciation" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_WarrantOrRightsPercentageOfOutstandingDebtPrincipalToPurchase" name="WarrantOrRightsPercentageOfOutstandingDebtPrincipalToPurchase" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <xsd:element id="fdus_WeightedAverageDiscountToNetAssetValue" name="WeightedAverageDiscountToNetAssetValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_WeightedAverageOfferingPriceOfCommonStock" name="WeightedAverageOfferingPriceOfCommonStock" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_WeightedAveragePriceOfCommonStockUnderAtTheMarketProgram" name="WeightedAveragePriceOfCommonStockUnderAtTheMarketProgram" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_WrittenNoticePeriodForTerminationOfAgreement" name="WrittenNoticePeriodForTerminationOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AbilityToEnterIntoAndExitInvestmentTransactionsWithAffiliatesWillBeRestrictedMember" name="AbilityToEnterIntoAndExitInvestmentTransactionsWithAffiliatesWillBeRestrictedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AbilityToInvolvingDerivativesAndUnfundedCommitmentTransactionsMayBeLimitedMember" name="AbilityToInvolvingDerivativesAndUnfundedCommitmentTransactionsMayBeLimitedMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AcendreMidcoIncMember" name="AcendreMidcoIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AcendreMidcoIncRevolvingLoanMember" name="AcendreMidcoIncRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AdministrationAgreementMember" name="AdministrationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AeronixIncMember" name="AeronixIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AerospaceAndDefenseManufacturingMember" name="AerospaceAndDefenseManufacturingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AffiliateInvestmentMember" name="AffiliateInvestmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AffiliateInvestmentsMember" name="AffiliateInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AllrediLlcMember" name="AllrediLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AmericanAllwasteLlcMember" name="AmericanAllwasteLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AmeriwaterLlcMember" name="AmeriwaterLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AomIntermediateHoldcoLlcMember" name="AomIntermediateHoldcoLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ApmIntermediateHoldingsLlcMember" name="ApmIntermediateHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ApplegateGreenfiberIntermediateIncMember" name="ApplegateGreenfiberIntermediateIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AppliedDataCorporationMember" name="AppliedDataCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ArgoTurboserveCorporationMember" name="ArgoTurboserveCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AtTheMarketOfferingProgramMember" name="AtTheMarketOfferingProgramMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AutoCrmLlcMember" name="AutoCrmLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AvcInvestorsLlcMember" name="AvcInvestorsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BandonFitnessTexasIncMember" name="BandonFitnessTexasIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BBRoadwayAndSecuritySolutionsLlcMember" name="BBRoadwayAndSecuritySolutionsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BcmOneGroupHoldingsIncMember" name="BcmOneGroupHoldingsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BedfordPrecisionPartsLLCMember" name="BedfordPrecisionPartsLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BoardOfDirectorsChangeInvestmentObjectiveOperatingPoliciesAndStrategiesWithoutPriorNoticeOrStockholderApprovalMember" name="BoardOfDirectorsChangeInvestmentObjectiveOperatingPoliciesAndStrategiesWithoutPriorNoticeOrStockholderApprovalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BorrowMoneyAndInFutureIssueAdditionalSeniorSecuritiesMayIncreaseRiskOfInvestingInCompanyMember" name="BorrowMoneyAndInFutureIssueAdditionalSeniorSecuritiesMayIncreaseRiskOfInvestingInCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BpThriftBuyerLlcMember" name="BpThriftBuyerLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BuildingProductsManufacturingMember" name="BuildingProductsManufacturingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_BusinessServicesMember" name="BusinessServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CapitalMarketsDisruptionAndEconomicUncertaintyMember" name="CapitalMarketsDisruptionAndEconomicUncertaintyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CardbackIntermediateLLCMember" name="CardbackIntermediateLLCMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CardboardBoxLlcDbaAnthonysCoalFiredPizzaMember" name="CardboardBoxLlcDbaAnthonysCoalFiredPizzaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChangeInInterestRateAffectCostOfCapitalAndNetInvestmentIncomeMember" name="ChangeInInterestRateAffectCostOfCapitalAndNetInvestmentIncomeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChangesInHealthcareLawsAndOtherRegulationsApplicableToPortfolioCompaniesMember" name="ChangesInHealthcareLawsAndOtherRegulationsApplicableToPortfolioCompaniesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChangesInLawsOrRegulationsGoverningOperationsMember" name="ChangesInLawsOrRegulationsGoverningOperationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChangesRelatedToDiscontinuationOfLiborMember" name="ChangesRelatedToDiscontinuationOfLiborMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChangesToUSTariffAndImportExportRegulationsMember" name="ChangesToUSTariffAndImportExportRegulationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChoiceTechnologySolutionsLlcDbaChoiceMerchantSolutionsLlcRevolvingLoanMember" name="ChoiceTechnologySolutionsLlcDbaChoiceMerchantSolutionsLlcRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ChoiceTechnologySolutionsLlcMember" name="ChoiceTechnologySolutionsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CihIntermediateLlcMember" name="CihIntermediateLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CombinedSystemsIncMember" name="CombinedSystemsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CombinedSystemsIncRevolvingLoanMember" name="CombinedSystemsIncRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonAndPreferredEquityUnitsMember" name="CommonAndPreferredEquityUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityClassATwoMember" name="CommonEquityClassATwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityClassBUnitsOneMember" name="CommonEquityClassBUnitsOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityEighteenMember" name="CommonEquityEighteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFiftyFiveMember" name="CommonEquityFiftyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFiftyFourMember" name="CommonEquityFiftyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFiftySevenMember" name="CommonEquityFiftySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFiftySixMember" name="CommonEquityFiftySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFiftyThreeMember" name="CommonEquityFiftyThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFiftyTwoMember" name="CommonEquityFiftyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityFortyNineMember" name="CommonEquityFortyNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityNineteenMember" name="CommonEquityNineteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesFortyMember" name="CommonEquitySharesFortyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesFortyOneMember" name="CommonEquitySharesFortyOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesOneMember" name="CommonEquitySharesOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyEightMember" name="CommonEquitySharesThirtyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyFiveMember" name="CommonEquitySharesThirtyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyFourMember" name="CommonEquitySharesThirtyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyMember" name="CommonEquitySharesThirtyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyOneMember" name="CommonEquitySharesThirtyOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtySevenMember" name="CommonEquitySharesThirtySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtySixMember" name="CommonEquitySharesThirtySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyThreeMember" name="CommonEquitySharesThirtyThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesThirtyTwoMember" name="CommonEquitySharesThirtyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesTwentyEightMember" name="CommonEquitySharesTwentyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesTwentyNineMember" name="CommonEquitySharesTwentyNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesTwentySevenMember" name="CommonEquitySharesTwentySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySharesTwentySixMember" name="CommonEquitySharesTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySixtyFiveMember" name="CommonEquitySixtyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquitySixtySixMember" name="CommonEquitySixtySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentyFiveMember" name="CommonEquityTwentyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentyFourMember" name="CommonEquityTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentyMember" name="CommonEquityTwentyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentyOneMember" name="CommonEquityTwentyOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentySixMember" name="CommonEquityTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentyThreeMember" name="CommonEquityTwentyThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityTwentyTwoMember" name="CommonEquityTwentyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsEighteenMember" name="CommonEquityUnitsEighteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsEightMember" name="CommonEquityUnitsEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsElevenMember" name="CommonEquityUnitsElevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFifteenMember" name="CommonEquityUnitsFifteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyEightMember" name="CommonEquityUnitsFiftyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyFiveMember" name="CommonEquityUnitsFiftyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyFourMember" name="CommonEquityUnitsFiftyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyMember" name="CommonEquityUnitsFiftyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyNineMember" name="CommonEquityUnitsFiftyNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyOneMember" name="CommonEquityUnitsFiftyOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftySevenMember" name="CommonEquityUnitsFiftySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftySixMember" name="CommonEquityUnitsFiftySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyThreeMember" name="CommonEquityUnitsFiftyThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiftyTwoMember" name="CommonEquityUnitsFiftyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFiveMember" name="CommonEquityUnitsFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortyEightMember" name="CommonEquityUnitsFortyEightMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortyFiveMember" name="CommonEquityUnitsFortyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortyFourMember" name="CommonEquityUnitsFortyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortySevenMember" name="CommonEquityUnitsFortySevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortySixMember" name="CommonEquityUnitsFortySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortyThreeMember" name="CommonEquityUnitsFortyThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFortyTwoMember" name="CommonEquityUnitsFortyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFourMember" name="CommonEquityUnitsFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsFourteenMember" name="CommonEquityUnitsFourteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsMember" name="CommonEquityUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsNineMember" name="CommonEquityUnitsNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsOneMember" name="CommonEquityUnitsOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSevenMember" name="CommonEquityUnitsSevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSeventeenMember" name="CommonEquityUnitsSeventeenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixMember" name="CommonEquityUnitsSixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixteenMember" name="CommonEquityUnitsSixteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtyFiveMember" name="CommonEquityUnitsSixtyFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtyFourMember" name="CommonEquityUnitsSixtyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtyMember" name="CommonEquityUnitsSixtyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtyOneMember" name="CommonEquityUnitsSixtyOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtySixMember" name="CommonEquityUnitsSixtySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtyThreeMember" name="CommonEquityUnitsSixtyThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsSixtyTwoMember" name="CommonEquityUnitsSixtyTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsTenMember" name="CommonEquityUnitsTenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsThirteenMember" name="CommonEquityUnitsThirteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsThirtyNineMember" name="CommonEquityUnitsThirtyNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsThreeMember" name="CommonEquityUnitsThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsTwelveMember" name="CommonEquityUnitsTwelveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsTwelveOneMember" name="CommonEquityUnitsTwelveOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsTwelveTwoMember" name="CommonEquityUnitsTwelveTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonEquityUnitsTwoMember" name="CommonEquityUnitsTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ComplyThreeHundredAndSixtyFiveLlcMember" name="ComplyThreeHundredAndSixtyFiveLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ComponentManufacturingMember" name="ComponentManufacturingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ConflictsWithInvestmentAdvisorRelatedToOtherArrangementsMember" name="ConflictsWithInvestmentAdvisorRelatedToOtherArrangementsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ConsumerProductsMember" name="ConsumerProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ConsumerProductsSectorMember" name="ConsumerProductsSectorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ControlInvestmentsMember" name="ControlInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ControlManyOfPortfolioCompaniesMember" name="ControlManyOfPortfolioCompaniesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_Covid19PandemicMember" name="Covid19PandemicMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CreditLossRiskMember" name="CreditLossRiskMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CrsSolutionsHoldingsLlcMember" name="CrsSolutionsHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CtmGroupIncMember" name="CtmGroupIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CurrentMarketConditionsMember" name="CurrentMarketConditionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CurrentTaxLiabilityOnDistributionsElectToReinvestCommonStockMember" name="CurrentTaxLiabilityOnDistributionsElectToReinvestCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CybersecurityRisksAndCyberIncidentsMember" name="CybersecurityRisksAndCyberIncidentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DataguiseIncMember" name="DataguiseIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DebtInvestmentsSubordinatedToClaimsOfOtherCreditorsOrSubjectToLenderLiabilityClaimsMember" name="DebtInvestmentsSubordinatedToClaimsOfOtherCreditorsOrSubjectToLenderLiabilityClaimsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DebtSecuritiesOfLeveragedCompaniesThatMayExperienceBankruptcyOrSimilarFinancialDistressMember" name="DebtSecuritiesOfLeveragedCompaniesThatMayExperienceBankruptcyOrSimilarFinancialDistressMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DefaultsByPortfolioCompaniesMember" name="DefaultsByPortfolioCompaniesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DelayedDrawCommitmentFourMember" name="DelayedDrawCommitmentFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_DelayedDrawCommitmentThreeMember" name="DelayedDrawCommitmentThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_DispositionOfInvestmentsMayResultInContingentLiabilitiesMember" name="DispositionOfInvestmentsMayResultInContingentLiabilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_EnvironmentalIndustriesMember" name="EnvironmentalIndustriesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_EnvironmentalSocialAndGovernanceFactorsMember" name="EnvironmentalSocialAndGovernanceFactorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_FailureToManageBusinessAndFutureGrowthMaterialAdverseEffectOnBusinessFinancialConditionAndResultsOfOperationsMember" name="FailureToManageBusinessAndFutureGrowthMaterialAdverseEffectOnBusinessFinancialConditionAndResultsOfOperationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_FinancialConditionAndResultsOfOperationDependsOnAbilityToManageBusinessEffectivelyMember" name="FinancialConditionAndResultsOfOperationDependsOnAbilityToManageBusinessEffectivelyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_FirstLienDebtFiveMember" name="FirstLienDebtFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_FivePointThreeFourFourPercentInterestRateMember" name="FivePointThreeFourFourPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_GlobalClimateChangeMember" name="GlobalClimateChangeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_GoldmanSachsFinancialSquareTreasuryObligationInstitutionCusipMember" name="GoldmanSachsFinancialSquareTreasuryObligationInstitutionCusipMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_HighlyCompetitiveMarketForInvestmentOpportunitiesMember" name="HighlyCompetitiveMarketForInvestmentOpportunitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_HilcoPlasticsHoldingsLlcMember" name="HilcoPlasticsHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_InternalAndExternalCyberThreatsAndOtherDisasterMember" name="InternalAndExternalCyberThreatsAndOtherDisasterMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_InvestmentInOurSecuritiesMayInvolveAboveAverageDegreeOfRiskMember" name="InvestmentInOurSecuritiesMayInvolveAboveAverageDegreeOfRiskMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_InvestmentsInCertainIndustrySectorsEnergySectorMayBeSubjectToSignificantPoliticalEconomicAndCapacityRisksMember" name="InvestmentsInCertainIndustrySectorsEnergySectorMayBeSubjectToSignificantPoliticalEconomicAndCapacityRisksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_InvestmentsInPortfolioCompaniesInvolvesNumberOfSignificantRisksMember" name="InvestmentsInPortfolioCompaniesInvolvesNumberOfSignificantRisksMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_IssueOfPreferredStockAndOrDebtSecuritiesNetAssetValueAndMarketValueOfCommonStockMember" name="IssueOfPreferredStockAndOrDebtSecuritiesNetAssetValueAndMarketValueOfCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
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  <xsd:element id="fdus_LackOfLiquidityMember" name="LackOfLiquidityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_LegislativeOrOtherActionsRelatingToTaxesMember" name="LegislativeOrOtherActionsRelatingToTaxesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_LevelEducationGroupLlcMember" name="LevelEducationGroupLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_LifespanBiosciencesIncMember" name="LifespanBiosciencesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_LimitedPartnershipAgreementMember" name="LimitedPartnershipAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MagentaBuyerLlcDbaTrellixMember" name="MagentaBuyerLlcDbaTrellixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ManagementAndIncentiveFeeStructureForInvestmentAdvisorNotFullyAlignedWithStockholdersAndMayEncourageToMakeSpeculativeInvestmentMember" name="ManagementAndIncentiveFeeStructureForInvestmentAdvisorNotFullyAlignedWithStockholdersAndMayEncourageToMakeSpeculativeInvestmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MarketConditionsMember" name="MarketConditionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MayNotHaveFundsToMakeAdditionalInvestmentMember" name="MayNotHaveFundsToMakeAdditionalInvestmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MayNotRealizeGainsFromEquityInvestmentMember" name="MayNotRealizeGainsFromEquityInvestmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MbsOpcoLlcDbaMarketronMember" name="MbsOpcoLlcDbaMarketronMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MeasurementInputAssetCoverageMember" name="MeasurementInputAssetCoverageMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MeasurementInputWeightedAverageCostOfCapitalMember" name="MeasurementInputWeightedAverageCostOfCapitalMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MedsurantHoldingsLlcMember" name="MedsurantHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MesaLineServicesLlcMember" name="MesaLineServicesLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MicronicsFiltrationHoldingsIncDbaMicronicsEngineeredFiltrationGroupIncMember" name="MicronicsFiltrationHoldingsIncDbaMicronicsEngineeredFiltrationGroupIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MidwestTransitEquipmentIncMember" name="MidwestTransitEquipmentIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MinimumDistributionRequirementToMaintainStatusAsRicMember" name="MinimumDistributionRequirementToMaintainStatusAsRicMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MirageTrailersLlcMember" name="MirageTrailersLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_MobilewallaIncMember" name="MobilewallaIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NetbaseSolutionsIncDbaNetbaseQuidFirstLienDebtLastOutMember" name="NetbaseSolutionsIncDbaNetbaseQuidFirstLienDebtLastOutMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NetbaseSolutionsIncDbaNetbaseQuidFirstLienDebtLastOutOneMember" name="NetbaseSolutionsIncDbaNetbaseQuidFirstLienDebtLastOutOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NetbaseSolutionsIncMember" name="NetbaseSolutionsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NewTaxLegislationMember" name="NewTaxLegislationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NgtAcquisitionHoldingsLlcDbaTechniksIndustriesMember" name="NgtAcquisitionHoldingsLlcDbaTechniksIndustriesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NonControlOrNonAffiliateInvestmentsMember" name="NonControlOrNonAffiliateInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NonDiversifiedInvestmentCompanyMember" name="NonDiversifiedInvestmentCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NotesMember" name="NotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_November2024NotesMember" name="November2024NotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_November2026NotesMember" name="November2026NotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ObligatedToPayInvestmentAdvisorIncentiveCompensationMember" name="ObligatedToPayInvestmentAdvisorIncentiveCompensationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_OilAndGasServicesMember" name="OilAndGasServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_OmcInvestorsLlcDbaOhioMedicalCorporationMember" name="OmcInvestorsLlcDbaOhioMedicalCorporationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_OnepathSystemsLlcMember" name="OnepathSystemsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_OnePointThreeNineEightPercentInterestRateMember" name="OnePointThreeNineEightPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_OtherPerformanceBasedIncentiveFeesMember" name="OtherPerformanceBasedIncentiveFeesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PalisadeCompanyLlcMember" name="PalisadeCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PalmettoMoonLlcMember" name="PalmettoMoonLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PayDividendsInOwnStockMayRequiredToPayTaxInExcessOfCashMember" name="PayDividendsInOwnStockMayRequiredToPayTaxInExcessOfCashMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PfanstiehlIncMember" name="PfanstiehlIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PfanstiehlLtdMember" name="PfanstiehlLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PinnergyLtdMember" name="PinnergyLtdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PoolAndElectricalProductsLlcMember" name="PoolAndElectricalProductsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PortfolioCompaniesMayIncurDebtThatRanksEquallyWithOrSeniorMember" name="PortfolioCompaniesMayIncurDebtThatRanksEquallyWithOrSeniorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PotentialConflictsOfInterestRelatedToObligationsOfInvestmentAdvisorMember" name="PotentialConflictsOfInterestRelatedToObligationsOfInvestmentAdvisorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PowerGridComponentsIncMember" name="PowerGridComponentsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PowergridServicesAcquisitionLlcMember" name="PowergridServicesAcquisitionLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityClassAUnitsOneMember" name="PreferredEquityClassAUnitsOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityClassBUnitsMember" name="PreferredEquityClassBUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityClassCUnitsTwoMember" name="PreferredEquityClassCUnitsTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityMember" name="PreferredEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquitySharesOneMember" name="PreferredEquitySharesOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquitySharesTenMember" name="PreferredEquitySharesTenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitNineMember" name="PreferredEquityUnitNineMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsEighteenMember" name="PreferredEquityUnitsEighteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsElevenMember" name="PreferredEquityUnitsElevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsFifteenMember" name="PreferredEquityUnitsFifteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsFourMember" name="PreferredEquityUnitsFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsFourteenMember" name="PreferredEquityUnitsFourteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsNineteenMember" name="PreferredEquityUnitsNineteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsOneMember" name="PreferredEquityUnitsOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsSevenMember" name="PreferredEquityUnitsSevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsSeventeenMember" name="PreferredEquityUnitsSeventeenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsSixMember" name="PreferredEquityUnitsSixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsSixteenMember" name="PreferredEquityUnitsSixteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsTenMember" name="PreferredEquityUnitsTenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsThirteenMember" name="PreferredEquityUnitsThirteenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsThreeMember" name="PreferredEquityUnitsThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsTwelveMember" name="PreferredEquityUnitsTwelveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsTwentyMember" name="PreferredEquityUnitsTwentyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitsTwoMember" name="PreferredEquityUnitsTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PreferredEquityUnitTwoMember" name="PreferredEquityUnitTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PrepaymentsOfDebtInvestmentsByPortfolioCompaniesMember" name="PrepaymentsOfDebtInvestmentsByPortfolioCompaniesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PrimaryInvestmentsDeemedNotToBeQualifyingAssetsMember" name="PrimaryInvestmentsDeemedNotToBeQualifyingAssetsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PrimeAeGroupIncMember" name="PrimeAeGroupIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PromotionalProductsMember" name="PromotionalProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ProvisionsOfMarylandGeneralCorporationLawMember" name="ProvisionsOfMarylandGeneralCorporationLawMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_PughLubricantsLlcMember" name="PughLubricantsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_QedParentHoldingsIncMember" name="QedParentHoldingsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_QuarterlyDividendMember" name="QuarterlyDividendMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_QuestSoftwareUsHoldingsIncMember" name="QuestSoftwareUsHoldingsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_R1HoldingsLlcDbaRoadoneIntermodalogisticsCommonEquityMember" name="R1HoldingsLlcDbaRoadoneIntermodalogisticsCommonEquityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_R1HoldingsLlcDbaRoadoneIntermodalogisticsFirstLienDebtMember" name="R1HoldingsLlcDbaRoadoneIntermodalogisticsFirstLienDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_R1HoldingsLlcDbaRoadoneIntermodalogisticsSeniorSubordinatedDebtMember" name="R1HoldingsLlcDbaRoadoneIntermodalogisticsSeniorSubordinatedDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RaymondJamesAndAssociatesIncAndRobertWBairdAndCoMember" name="RaymondJamesAndAssociatesIncAndRobertWBairdAndCoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RegulationsGoverningOperationsAsBdcMember" name="RegulationsGoverningOperationsAsBdcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RenductionInAssetCoverageRequirementMayIncreaseRiskOfInvestingInCompanyMember" name="RenductionInAssetCoverageRequirementMayIncreaseRiskOfInvestingInCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ResignationOfInvestmentAdvisorFromAdministratorRoleUnderAdministrationAgreementMember" name="ResignationOfInvestmentAdvisorFromAdministratorRoleUnderAdministrationAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ResignationOfInvestmentAdvisorMember" name="ResignationOfInvestmentAdvisorMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RestaurantsMember" name="RestaurantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RetailSectorsMember" name="RetailSectorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanFiveMember" name="RevolvingLoanFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanFourMember" name="RevolvingLoanFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanMember" name="RevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanOneMember" name="RevolvingLoanOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanSixMember" name="RevolvingLoanSixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanThreeMember" name="RevolvingLoanThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RevolvingLoanTwoMember" name="RevolvingLoanTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RhinoAssemblyCompanyLlcDelayedDrawCommitmentMember" name="RhinoAssemblyCompanyLlcDelayedDrawCommitmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RhinoAssemblyCompanyLlcMember" name="RhinoAssemblyCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RiskRelatedToInflationMember" name="RiskRelatedToInflationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RisksRelatingToOurBusinessAndStructureMember" name="RisksRelatingToOurBusinessAndStructureMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RisksRelatingToOurCommonStockMember" name="RisksRelatingToOurCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RisksRelatingToOurInvestmentsMember" name="RisksRelatingToOurInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_RoadSafetyServicesIncMember" name="RoadSafetyServicesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ROneHoldingsLlcMember" name="ROneHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SafetyProductsGroupLlcCommonEquityUnitsMember" name="SafetyProductsGroupLlcCommonEquityUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SalesOfSubstantialAmountsOfCommonStockMember" name="SalesOfSubstantialAmountsOfCommonStockMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SbaRegulationsLimitAmountAvailableToBeBorrowedBySbicMember" name="SbaRegulationsLimitAmountAvailableToBeBorrowedBySbicMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SbaRegulationsMember" name="SbaRegulationsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SecondLienDebtMember" name="SecondLienDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SecondPriorityLiensOnCollateralSecuringLoansMayBeSubjectToControlBySeniorCreditorsWithFirstPriorityLienMember" name="SecondPriorityLiensOnCollateralSecuringLoansMayBeSubjectToControlBySeniorCreditorsWithFirstPriorityLienMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SecuredBorrowingsMember" name="SecuredBorrowingsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SeniorSecuredRevolvingCreditAgreementMember" name="SeniorSecuredRevolvingCreditAgreementMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SeniorSecuredRevolvingCreditFacilityMember" name="SeniorSecuredRevolvingCreditFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SesInvestorsLlcDbaSesFoamMember" name="SesInvestorsLlcDbaSesFoamMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SharesTradeAtDiscountToNetAssetValueMember" name="SharesTradeAtDiscountToNetAssetValueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SignificantChangeInNetAssetValueMember" name="SignificantChangeInNetAssetValueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SignificantFluctualtionOnMarketPriceOfSecuritiesMember" name="SignificantFluctualtionOnMarketPriceOfSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SixPointZeroZeroZeroPercentNotesDueTwoThousandTwentyFourMember" name="SixPointZeroZeroZeroPercentNotesDueTwoThousandTwentyFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SixteenAndSeventeenPortfolioCompanyInvestmentsMember" name="SixteenAndSeventeenPortfolioCompanyInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SmallBusinessAdministrationDebenturesMember" name="SmallBusinessAdministrationDebenturesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SonicwallUsHoldingsIncMember" name="SonicwallUsHoldingsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SpecialDividendMember" name="SpecialDividendMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SpecialtyChemicalsMember" name="SpecialtyChemicalsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SpecialtyDistributionMember" name="SpecialtyDistributionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SpectraAAndDAcquisitionIncMember" name="SpectraAAndDAcquisitionIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SpendmendLlcMember" name="SpendmendLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_StewardHoldingLlcMember" name="StewardHoldingLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_StockholdersNotParticipateInShareTradeAtDiscountToNetAssetValuePerShareMayExperienceImmediateDilutionMember" name="StockholdersNotParticipateInShareTradeAtDiscountToNetAssetValuePerShareMayExperienceImmediateDilutionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SubjectToSecuritiesLitigationOrShareholderActivismCauseToIncurSignificantExpenseHinderExecutionOfInvestmentStrategyAndImpactOurStockPriceMember" name="SubjectToSecuritiesLitigationOrShareholderActivismCauseToIncurSignificantExpenseHinderExecutionOfInvestmentStrategyAndImpactOurStockPriceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SubjectToUSFederalIncomeTaxAtCorporateRatesMember" name="SubjectToUSFederalIncomeTaxAtCorporateRatesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SubordinatedDebtOneMember" name="SubordinatedDebtOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SuitedConnectorLlcMember" name="SuitedConnectorLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SummaryOfRiskFactorsMember" name="SummaryOfRiskFactorsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SupplementalDividendMember" name="SupplementalDividendMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SupplementalDividendOneMember" name="SupplementalDividendOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SupplementalDividendTwoMember" name="SupplementalDividendTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TediaCompanyLlcDelayedDrawTermLoanMember" name="TediaCompanyLlcDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TediaCompanyLlcMember" name="TediaCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TediaCompanyLlcRevolvingLoanMember" name="TediaCompanyLlcRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TerroristAttacksActsOfWarOrNaturalDisastersMember" name="TerroristAttacksActsOfWarOrNaturalDisastersMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TheKyjenCompanyLlcMember" name="TheKyjenCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TheTranzonicCompaniesMember" name="TheTranzonicCompaniesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointFiveThreeFourPercentInterestRateMember" name="ThreePointFiveThreeFourPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointFiveZeroPercentNotesDueTwoThousandTwentySixMember" name="ThreePointFiveZeroPercentNotesDueTwoThousandTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointOneNineZeroPercentInterestRateMember" name="ThreePointOneNineZeroPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointTwoFourNinePercentInterestRateMember" name="ThreePointTwoFourNinePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointTwoSevenSevenPercentInterestRateMember" name="ThreePointTwoSevenSevenPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointTwoSixSevenPercentInterestRateMember" name="ThreePointTwoSixSevenPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointTwoSixZeroPercentInterestRateMember" name="ThreePointTwoSixZeroPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ThreePointTwoZeroNinePercentInterestRateMember" name="ThreePointTwoZeroNinePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TigerCalciumServicesIncMember" name="TigerCalciumServicesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TotalInvestmentsMember" name="TotalInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheFiveMember" name="TrancheFiveMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheFourMember" name="TrancheFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheOneMember" name="TrancheOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheSevenMember" name="TrancheSevenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheSixMember" name="TrancheSixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheThreeMember" name="TrancheThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TrancheTwoMember" name="TrancheTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TransgoLlcMember" name="TransgoLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TransportationServicesMember" name="TransportationServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwentyTwentyThreeNotesMember" name="TwentyTwentyThreeNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwoKDirectIncMember" name="TwoKDirectIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwoPointOneSevenTwoPercentInterestRateMember" name="TwoPointOneSevenTwoPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwoPointSevenNineThreePercentInterestRateMember" name="TwoPointSevenNineThreePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwoPointThreeSevenSevenPercentInterestRateMember" name="TwoPointThreeSevenSevenPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwoThousandTwentyFourNotesMember" name="TwoThousandTwentyFourNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TwoThousandTwentyThreeNotesMember" name="TwoThousandTwentyThreeNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_TypicalRiskAssociatedWithOIDAndPIKInteretsIncomeMember" name="TypicalRiskAssociatedWithOIDAndPIKInteretsIncomeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UbeoLlcMember" name="UbeoLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnableToInvestSignificantPortionOfNetProceedsFromOofferingOrFromExitingIinvestmentOrOtherCapitalOnAcceptableTermMember" name="UnableToInvestSignificantPortionOfNetProceedsFromOofferingOrFromExitingIinvestmentOrOtherCapitalOnAcceptableTermMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnableToProtectIntellectualPropertyRightsMember" name="UnableToProtectIntellectualPropertyRightsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UncertaintyAboutUSPresidentialAdministrationInitiativesMember" name="UncertaintyAboutUSPresidentialAdministrationInitiativesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UncertaintySurroundingPotentialLegalRegulatoryAndPolicyChangesByCurrentPresidentialAdministrationsAndCongressMember" name="UncertaintySurroundingPotentialLegalRegulatoryAndPolicyChangesByCurrentPresidentialAdministrationsAndCongressMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitedBiologicsLlcMember" name="UnitedBiologicsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitedStatesMidwestMember" name="UnitedStatesMidwestMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitedStatesNortheastMember" name="UnitedStatesNortheastMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitedStatesSoutheastMember" name="UnitedStatesSoutheastMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitedStatesSouthwestMember" name="UnitedStatesSouthwestMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitedStatesWestMember" name="UnitedStatesWestMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnitrancheInvestmentsMember" name="UnitrancheInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnrealizedDepreciationOnInvestmentPortfolioMayBeIndicationOfFutureRealizedLossesMember" name="UnrealizedDepreciationOnInvestmentPortfolioMayBeIndicationOfFutureRealizedLossesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UpgCompanyLlcMember" name="UpgCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UsgAsHoldingsLlcMember" name="UsgAsHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UsGreenfiberLlcMember" name="UsGreenfiberLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UtilitiesServicesMember" name="UtilitiesServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UtilityEquipmentManufacturingMember" name="UtilityEquipmentManufacturingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ValuationTechniqueEnterpriseValueMember" name="ValuationTechniqueEnterpriseValueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ValueOfPortfolioInvestmentAndValuationProcessCreatesConflictOfInterestMember" name="ValueOfPortfolioInvestmentAndValuationProcessCreatesConflictOfInterestMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_VendingEquipmentManufacturingMember" name="VendingEquipmentManufacturingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_VirginiaTileCompanyLlcMember" name="VirginiaTileCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_VirtexEnterprisesLpMember" name="VirtexEnterprisesLpMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WaiverMember" name="WaiverMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WarrantSharesThreeMember" name="WarrantSharesThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WarrantsNotesMember" name="WarrantsNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WarrantUnitsOneMember" name="WarrantUnitsOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WarrantUnitsThreeMember" name="WarrantUnitsThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WarrantUnitsTwoMember" name="WarrantUnitsTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WesternsSmokehouseLlcDelayedDrawTermLoanMember" name="WesternsSmokehouseLlcDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WesternsSmokehouseLlcMember" name="WesternsSmokehouseLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WinonaFoodsIncMember" name="WinonaFoodsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WonderwareHoldingsLlcDbaCoreBusinessTechnologiesDelayedDrawTermLoanMember" name="WonderwareHoldingsLlcDbaCoreBusinessTechnologiesDelayedDrawTermLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WonderwareHoldingsLlcDbaCoreBusinessTechnologiesMember" name="WonderwareHoldingsLlcDbaCoreBusinessTechnologiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WorldwideExpressOperationsLlcMember" name="WorldwideExpressOperationsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_XeevaIncMember" name="XeevaIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ZeroPointNineOnePercentInterestRateMember" name="ZeroPointNineOnePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ZonkdLlcMember" name="ZonkdLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DeferredFinancingCostsPolicyTextBlock" name="DeferredFinancingCostsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_DividendsAndDistributionsTextBlock" name="DividendsAndDistributionsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_FeeIncomePolicyTextBlock" name="FeeIncomePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InterestAndDividendIncomePolicyTextBlock" name="InterestAndDividendIncomePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_InvestmentRiskPolicyTextBlock" name="InvestmentRiskPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_NonAccrualPolicyTextBlock" name="NonAccrualPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_OriginationAndClosingFee" name="OriginationAndClosingFee" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PartialLoanAndEquitySalesPolicyTextBlock" name="PartialLoanAndEquitySalesPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_PaymentInKindIncomePolicyTextBlock" name="PaymentInKindIncomePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_RealizedGainsOrLossesAndUnrealizedAppreciationOrDepreciationOnInvestmentsPolicyTextBlock" name="RealizedGainsOrLossesAndUnrealizedAppreciationOrDepreciationOnInvestmentsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_RealizedLossesOnExtinguishmentOfDebtPolicyTextBlock" name="RealizedLossesOnExtinguishmentOfDebtPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_ScheduleOfExpenseRatiosToAverageNetAssetsTableTextBlock" name="ScheduleOfExpenseRatiosToAverageNetAssetsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_ScheduleOfInformationAboutSeniorSecuritiesTableTextBlock" name="ScheduleOfInformationAboutSeniorSecuritiesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_ScheduleOfInterestAndFinancingExpensesRelatedToDebtTableTextBlock" name="ScheduleOfInterestAndFinancingExpensesRelatedToDebtTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_StockRepurchaseProgramPolicyTextBlock" name="StockRepurchaseProgramPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfCommonStockAtmProgram1TableTextBlock" name="SummaryOfCommonStockAtmProgram1TableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfCommonStockTableTextBlock" name="SummaryOfCommonStockTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfDeferredFinancingCostsAmortizedIntoInterestAndFinancingExpensesTableTextBlock" name="SummaryOfDeferredFinancingCostsAmortizedIntoInterestAndFinancingExpensesTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfOutstandingCommitmentsTableTextBlock" name="SummaryOfOutstandingCommitmentsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfPermanentBookToTaxDifferenceOfAdditionalPaidInCapitalAndTotalDistributableEarnings" name="SummaryOfPermanentBookToTaxDifferenceOfAdditionalPaidInCapitalAndTotalDistributableEarnings" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfReconciliationTaxableIncomeAndTotalDistributionsDeclaredToCommonStockholdersTableTextBlock" name="SummaryOfReconciliationTaxableIncomeAndTotalDistributionsDeclaredToCommonStockholdersTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfRepurchaseOfCommonStockTableTextBlock" name="SummaryOfRepurchaseOfCommonStockTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfTaxBasisComponentsOfDistributableEarningsTableTextBlock" name="SummaryOfTaxBasisComponentsOfDistributableEarningsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfTaxCharacterOfDistributionsToCommonStockholders" name="SummaryOfTaxCharacterOfDistributionsToCommonStockholders" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_SummaryOfUnamortizedDeferredFinancingCostsTableTextBlock" name="SummaryOfUnamortizedDeferredFinancingCostsTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_WarrantsPolicyTextBlock" name="WarrantsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
</xsd:schema>
