Class Oligochaeta Grube, 1850 - oligochaetes see [unranked] oligochaetous Clitellata
Count: [f] 5o;27f
   Subclass Diplotesticulata
  Count: [f] 2o;19f
     Superorder Metagynophora Jamieson, 1988
    Count: [f] 2o;17f
       Order Opisthopora
      Count: [f] 16f
         Suborder Crassiclitellata
        Count: [f] 14f
           Cohort Aquamegadrili Jamieson, 1988
          Count: [f] 4f
             Superfamily Sparganophiloidea
            Count: [f] 1f
               Family Sparganophilidae
              Count: -