Key to the subgenera of Drymaeus

- Peristome usually expanded, suture straight or ascending behind the peristome; mandibula with 13-18 plates, which are 4-5 times as long as wide; transverse row of radula straight, with relatively large, mono- to tricuspid central teeth and bi- to tricupid lateromarginal teeth... Subgenus Drymaeus s. str.
- Peristome usually simple, suture straight or descending in front; mandibula with more than 20 plates, which are ca. 8 times as long as wide; transverse rows of radula V- or W-shaped, with relatively small tri- to multicuspid central and lateromarginal teeth ... Subgenus Drymaeus (Mesembrinus)

Distribution. Venezuela, Guyana, Suriname, French Guiana, Brazil, Uruguay, Paraguay, Argentina, Bolivia, Peru, Ecuador, Colombia, Panama, Costa Rica, Nicaragua, El Salvador, Honduras, Guatemala, Belize, Mexico, U.S.A., Caribbean (most islands).