Their species can be found sporadically in caves, groundwater, and deep lakes in Central Asia, Far East and North America.

[4] Kenkiidae species have the testicles situated anterior to the pharynx, feature also common in the Dugesiidae and Planariidae.

They have an anterior adhesive organ, which is also found in the family Dendrocoelidae.

[2] Kenkiidae is the sister group of the family Dendrocoelidae.

[4][5] Phylogenetic supertree after Sluys et al., 2009:[5] Maricola Cavernicola Planariidae Kenkiidae Dendrocoelidae Dugesiidae Geoplanidae Data related to Kenkiidae at Wikispecies