Genus Trichodrilus Claparède,1862

Lumbriculids with two pairs of testes and one pair of ovaries. One pair of male ducts open typically in X, with a semiprosoporous organization, i.e. each atrium receives one pair of vasa deferentia which run independently from two sperm funnels serving separately testes in the pre-atrial and atrial segments. One pair of spermathecae opening in the ovarian segment; some species also have one additional pair in the post ovarian segment and one species with spermathecae in 4 postatrial segments.