 The taxonomy, anatomy and other aspects of the biology of this genus were reviewed in 2000, and the diverse mating behaviors were reviewed in 2007.In 2000, in the most recent monograph on the genus, Wiktor rejected earlier attempts (including his own) at a subgeneric ("Agriolimax" Mörch, 1865, "Plathystimulus" Wiktor, 1973) classification, because there appeared to be so many convergences and reversals.The only exception was that he split off "Liolytopelte" as a subgenus because of its distinctive hard plate within the penis; all other species were included in the subgenus "Deroceras".