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  <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_DelayedDrawCommitmentTwoMember" name="DelayedDrawCommitmentTwoMember" 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_DividendsAndDistributionsTextBlock" name="DividendsAndDistributionsTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_InvestmentVariableIndexSpreadRate" name="InvestmentVariableIndexSpreadRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_FirstLienDebtOneMember" name="FirstLienDebtOneMember" 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_FourPointFiveThreeThreePercentInterestRateMember" name="FourPointFiveThreeThreePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SixPointZeroEightThreePercentInterestRateMember" name="SixPointZeroEightThreePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_FairValueAssetsLevelTwoToLevelOneTransfersAmount" name="FairValueAssetsLevelTwoToLevelOneTransfersAmount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_PaymentsOfDividendsIncludingExpenses" name="PaymentsOfDividendsIncludingExpenses" 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_AldingerCompanyMember" name="AldingerCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_AccretionOfOriginalIssueDiscount" name="AccretionOfOriginalIssueDiscount" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_UtilitiesServicesMember" name="UtilitiesServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_RealizedLossesOnExtinguishmentOfDebtPolicyTextBlock" name="RealizedLossesOnExtinguishmentOfDebtPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_DeferredUpfrontFees" name="DeferredUpfrontFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_NetChangeInUnrealizedAppreciationDepreciationOnInvestments" name="NetChangeInUnrealizedAppreciationDepreciationOnInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" 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_UnitrancheInvestmentsMember" name="UnitrancheInvestmentsMember" 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_HallmarkHealthCareSolutionsIncMember" name="HallmarkHealthCareSolutionsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_UnderwritingFeesAndCommissionsUnderAtTheMarketProgram" name="UnderwritingFeesAndCommissionsUnderAtTheMarketProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_FivePointSevenThreeFivePercentInterestRateMember" name="FivePointSevenThreeFivePercentInterestRateMember" 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_SummaryOfOutstandingCommitmentsTableTextBlock" name="SummaryOfOutstandingCommitmentsTableTextBlock" 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_FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetInterestAndDividendIncomePaidInKind" name="FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisAssetInterestAndDividendIncomePaidInKind" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_PercentageOfPortfolioInvestmentsAtFairValue" name="PercentageOfPortfolioInvestmentsAtFairValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_RhinoAssemblyCompanyLlcDelayedDrawCommitmentMember" name="RhinoAssemblyCompanyLlcDelayedDrawCommitmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SeniorAssetCoverageRatio" name="SeniorAssetCoverageRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_RaymondJamesAndAssociatesIncAndRobertWBairdAndCoMember" name="RaymondJamesAndAssociatesIncAndRobertWBairdAndCoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ProceedsReceivableFromStockOffering" name="ProceedsReceivableFromStockOffering" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_K2MergerAgreementAgentLlcMember" name="K2MergerAgreementAgentLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_IncreaseDecreaseInPayablesForInvestmentsPurchased" name="IncreaseDecreaseInPayablesForInvestmentsPurchased" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_DebtInstrumentPoolingDate" name="DebtInstrumentPoolingDate" type="xbrli:dateItemType" 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_AffiliateInvestmentMember" name="AffiliateInvestmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_ValuationTechniqueEnterpriseValueMember" name="ValuationTechniqueEnterpriseValueMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DividendTwoMember" name="DividendTwoMember" 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_MidwestTransitEquipmentIncMember" name="MidwestTransitEquipmentIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AdministrativeServiceExpenses" name="AdministrativeServiceExpenses" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_ControlInvestmentsMember" name="ControlInvestmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_NwsTechnologiesLlcMember" name="NwsTechnologiesLlcMember" 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_MeasurementInputAssetCoverageMember" name="MeasurementInputAssetCoverageMember" 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_ThreePointTwoSixZeroPercentInterestRateMember" name="ThreePointTwoSixZeroPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_FairValueOfLoansIncludedInInvestments" name="FairValueOfLoansIncludedInInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_ProceedsFromSalesAndRepaymentsIncludingPrincipalReturnOfCapitalDistributionsAndRealizedGains" name="ProceedsFromSalesAndRepaymentsIncludingPrincipalReturnOfCapitalDistributionsAndRealizedGains" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_IncreaseDecreaseInReceivablesFromInvestmentsSold" name="IncreaseDecreaseInReceivablesFromInvestmentsSold" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_NumberOfInvestmentPorfolioCompanies" name="NumberOfInvestmentPorfolioCompanies" type="xbrli:integerItemType" 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_PfanstiehlIncMember" name="PfanstiehlIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_InvestmentAndMoneyMarketFundsOwnedPercentOfNetAssets" name="InvestmentAndMoneyMarketFundsOwnedPercentOfNetAssets" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_UnitedStatesNortheastMember" name="UnitedStatesNortheastMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_PercentageOfVotingSecurities" name="PercentageOfVotingSecurities" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_LineOfCreditFacilityMinimumUtilizationCommitmentFeePercentage" name="LineOfCreditFacilityMinimumUtilizationCommitmentFeePercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_FivePointEightSixOnePercentInterestRateThreeMember" name="FivePointEightSixOnePercentInterestRateThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_HaematologicTechnologiesIncMember" name="HaematologicTechnologiesIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_ApplegateGreenfiberIntermediateIncMember" name="ApplegateGreenfiberIntermediateIncMember" 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_CardbackIntermediateLLCMember" name="CardbackIntermediateLLCMember" 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_FivePointFourthreeNinePercentInterestRateMember" name="FivePointFourthreeNinePercentInterestRateMember" 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_InvestmentIncomePaymentInKindInterestIncome" name="InvestmentIncomePaymentInKindInterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_SpectraAAndDAcquisitionIncMember" name="SpectraAAndDAcquisitionIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_ProceedsFromSalesAndRepaymentsOfInvestments" name="ProceedsFromSalesAndRepaymentsOfInvestments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_FivePointNineEightThreePercentInterestRateMember" name="FivePointNineEightThreePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_FidusEquityFundILimitedPartnershipMember" name="FidusEquityFundILimitedPartnershipMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SecuredBorrowingsMember" name="SecuredBorrowingsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_FivePointEightSixOnePercentInterestRateTwoMember" name="FivePointEightSixOnePercentInterestRateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DividendReinvestmentPlanMember" name="DividendReinvestmentPlanMember" 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_CumulativeGrossProceedsFromIssuanceOfCommonStock" name="CumulativeGrossProceedsFromIssuanceOfCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_FivePointThreeFourOnePercentInterestRateOneMember" name="FivePointThreeFourOnePercentInterestRateOneMember" 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_InvestmentMaturityPeriod" name="InvestmentMaturityPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_OriginationAndClosingFee" name="OriginationAndClosingFee" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_FivePointEightSixOnePercentInterestRateOneMember" name="FivePointEightSixOnePercentInterestRateOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_NetbaseSolutionsIncDbaNetbaseQuidFirstLienDebtLastOutMember" name="NetbaseSolutionsIncDbaNetbaseQuidFirstLienDebtLastOutMember" 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_ZonkdLlcDelayedDrawTermLoanMember" name="ZonkdLlcDelayedDrawTermLoanMember" 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_PreIncentiveFeeFixedHurdleRate" name="PreIncentiveFeeFixedHurdleRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_FivePointThreeFourOnePercentInterestRateTwoMember" name="FivePointThreeFourOnePercentInterestRateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_ElementsBrandsLlcRevolvingLoanMember" name="ElementsBrandsLlcRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DebtInstrumentMaturityYearRangeEnd" name="DebtInstrumentMaturityYearRangeEnd" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_FarResearchIncMember" name="FarResearchIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_IproTechLlcMember" name="IproTechLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_EblLlcMember" name="EblLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_HealthcareProductsMember" name="HealthcareProductsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_EblLlcEblensCommonEquityUnitsMember" name="EblLlcEblensCommonEquityUnitsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AssetCoverageRatio" name="AssetCoverageRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_TediaCompanyLlcRevolvingLoanMember" name="TediaCompanyLlcRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_GpCOperationLlcMember" name="GpCOperationLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SbicDebentureProgramMaximumAmountOutstandingSbaDebentures" name="SbicDebentureProgramMaximumAmountOutstandingSbaDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_PaidInKindInterestIncome" name="PaidInKindInterestIncome" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_AccretionOfLoanOriginationFees" name="AccretionOfLoanOriginationFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_BedfordPrecisionPartsLLCMember" name="BedfordPrecisionPartsLLCMember" 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_NonAccrualPolicyTextBlock" name="NonAccrualPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_BurgerfiInternationalLlcMember" name="BurgerfiInternationalLlcMember" 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_DebentureLeverageFees" name="DebentureLeverageFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_FiberMaterialsIncMember" name="FiberMaterialsIncMember" 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_DebtInstrumentInterimInterestRate" name="DebtInstrumentInterimInterestRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_PercentageOfNonQualifyingAssetsFairValue" name="PercentageOfNonQualifyingAssetsFairValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_InvestmentCompanyTotalReturnBasedOnMarketValue" name="InvestmentCompanyTotalReturnBasedOnMarketValue" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" 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_GrossProceedsFromIssuanceOfCommonStockUnderAtTheMarketProgram" name="GrossProceedsFromIssuanceOfCommonStockUnderAtTheMarketProgram" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_GarlockPrintingAndConvertingOperationsLlcMember" name="GarlockPrintingAndConvertingOperationsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_WinonaFoodsIncMember" name="WinonaFoodsIncMember" 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_NumberOfInvestmentsRepresentedMoreThanTenPercentageOfAggregateInvestmentPortfolio" name="NumberOfInvestmentsRepresentedMoreThanTenPercentageOfAggregateInvestmentPortfolio" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" 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_FivePointThreeFourOnePercentInterestRateMember" name="FivePointThreeFourOnePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AggregateAmountOfOutstandingOfSeniorSecurities" name="AggregateAmountOfOutstandingOfSeniorSecurities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_InvestmentVariableIndexFloorRate" name="InvestmentVariableIndexFloorRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_FivePointEightSixOnePercentInterestRateMember" name="FivePointEightSixOnePercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_FourPointSevenFivePercentNotesDueTwoThousandTwentySixMember" name="FourPointSevenFivePercentNotesDueTwoThousandTwentySixMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_InterestAndDividendIncomePolicyTextBlock" name="InterestAndDividendIncomePolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AdditionalInterestRateOnInvestments" name="AdditionalInterestRateOnInvestments" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_InvestmentCompanyPortfolioTurnoverRatio" name="InvestmentCompanyPortfolioTurnoverRatio" 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_ChoiceTechnologySolutionsLlcDbaChoiceMerchantSolutionsLlcRevolvingLoanMember" name="ChoiceTechnologySolutionsLlcDbaChoiceMerchantSolutionsLlcRevolvingLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_RestaurantsMember" name="RestaurantsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CommonStockIssuedUnderAtTheMarketProgram" name="CommonStockIssuedUnderAtTheMarketProgram" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AdditionalInterestRateOnInvestmentsPaidInKind" name="AdditionalInterestRateOnInvestmentsPaidInKind" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_WeightedAveragePriceOfCommonStockUnderAtTheMarketProgram" name="WeightedAveragePriceOfCommonStockUnderAtTheMarketProgram" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AccruedCapitalGainsIncentiveFeePayable" name="AccruedCapitalGainsIncentiveFeePayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_AdministrationAgreementMember" name="AdministrationAgreementMember" 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_PercentageOfExciseTax" name="PercentageOfExciseTax" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false"/>
  <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_DebtInvestmentInNumberOfPortfolioCompaniesOnNonAccrualStatus" name="DebtInvestmentInNumberOfPortfolioCompaniesOnNonAccrualStatus" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <xsd:element id="fdus_AggregateAmountOfCapitalGainsIncentiveFees" name="AggregateAmountOfCapitalGainsIncentiveFees" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_InvestmentRepresentedMoreThanTenPercentageOfAggregateInvestmentPortfolio" name="InvestmentRepresentedMoreThanTenPercentageOfAggregateInvestmentPortfolio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_DividendsAndDistributionsAbstract" name="DividendsAndDistributionsAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_SixPointZeroFourSevenPercentInterestRateMember" name="SixPointZeroFourSevenPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SuitedConnectorLlcMember" name="SuitedConnectorLlcMember" 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_AccretiveDilutiveEffectOfShareIssuancesAndRepurchases" name="AccretiveDilutiveEffectOfShareIssuancesAndRepurchases" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_AeronixIncMember" name="AeronixIncMember" 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_UsGreenfiberLlcMember" name="UsGreenfiberLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_AccruedInterestAndFeesPayable" name="AccruedInterestAndFeesPayable" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <xsd:element id="fdus_WarrantsPolicyTextBlock" name="WarrantsPolicyTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_PowerGridComponentsIncMember" name="PowerGridComponentsIncMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_InterestOnIdleFunds" name="InterestOnIdleFunds" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_DealerbuiltAcquisitionLlcMember" name="DealerbuiltAcquisitionLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_AllrediLlcMember" name="AllrediLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_WinonaFoodsIncFirstLienDebtMember" name="WinonaFoodsIncFirstLienDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_EquityInvestmentMember" name="EquityInvestmentMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_MirageTrailersLlcMember" name="MirageTrailersLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_FivePointFourThreeNinePercentInterestRateTwoMember" name="FivePointFourThreeNinePercentInterestRateTwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_SecuredBorrowings" name="SecuredBorrowings" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_RepaymentsOfSmallBusinessAdministrationDebentures" name="RepaymentsOfSmallBusinessAdministrationDebentures" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_InvestmentsAndMoneyMarketFundsOwnedAtFairValue" name="InvestmentsAndMoneyMarketFundsOwnedAtFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <xsd:element id="fdus_FivePointThreeFourOnePercentInterestRateThreeMember" name="FivePointThreeFourOnePercentInterestRateThreeMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_QedTechnologiesInternationalIncMember" name="QedTechnologiesInternationalIncMember" 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_AmeriwaterLlcMember" name="AmeriwaterLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_AmericanAllwasteLlcDbaWasteWaterTransportServicesFirstLienDebtMember" name="AmericanAllwasteLlcDbaWasteWaterTransportServicesFirstLienDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_InformationTechnologyServicesMember" name="InformationTechnologyServicesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_CashDistribution" name="CashDistribution" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_UpgCompanyLlcMember" name="UpgCompanyLlcMember" 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_WhiteLabelCommunicationsLlcMember" name="WhiteLabelCommunicationsLlcMember" 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_SpecialDividendMember" name="SpecialDividendMember" 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_PaymentInKindIncomePolicyTextBlock" name="PaymentInKindIncomePolicyTextBlock" type="dtr-types:textBlockItemType" 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_FirstLienDebtMember" name="FirstLienDebtMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_FivePointNineEightEightPercentInterestRateMember" name="FivePointNineEightEightPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_AdministrationFeesPayableAndOtherDueToAffiliate" name="AdministrationFeesPayableAndOtherDueToAffiliate" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_MoneyMarketFundsAtFairValue" name="MoneyMarketFundsAtFairValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
  <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_Percentageoffairvalue" name="Percentageoffairvalue" 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_WesternsSmokehouseLlcMember" name="WesternsSmokehouseLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_CardboardBoxLlcDbaAnthonysCoalFiredPizzaMember" name="CardboardBoxLlcDbaAnthonysCoalFiredPizzaMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_OnePointThreeNineEightPercentInterestRateMember" name="OnePointThreeNineEightPercentInterestRateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_NetIncreaseDecreaseInNetAssetsResultingFromOperationsToCommonStockholdersBasicAndDiluted" name="NetIncreaseDecreaseInNetAssetsResultingFromOperationsToCommonStockholdersBasicAndDiluted" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_FidusInvestmentAdvisorsLlcMember" name="FidusInvestmentAdvisorsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_IngCapitalLimitedLiabilityCompanyMember" name="IngCapitalLimitedLiabilityCompanyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_NetRealizedGainLossOnInvestmentsNetOfTaxes" name="NetRealizedGainLossOnInvestmentsNetOfTaxes" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false" xbrli:balance="credit"/>
  <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_ApmIntermediateHoldingsLlcMember" name="ApmIntermediateHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_FivePointFourThreeNinePercentInterestRateOneMember" name="FivePointFourThreeNinePercentInterestRateOneMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <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_WrittenNoticePeriodForTerminationOfAgreement" name="WrittenNoticePeriodForTerminationOfAgreement" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="false"/>
  <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_January2026NotesMember" name="January2026NotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" nillable="true" abstract="true"/>
  <xsd:element id="fdus_DebtIssueCosts" name="DebtIssueCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" nillable="true" abstract="false" xbrli:balance="debit"/>
</xsd:schema>
