The sternum is also tan, sometimes darker, as wide as long, convex, and rounds towards the rear.

The abdomen is light grey or tan, with no clear markings, and bears sparse setae.

Although the genus is troglobitic, they have no specific modifications for living in caves or other dark places.

[2] Diagnostic features include: the base of the epigynum in female Plato species having a median projection; the cymbium having distal or mesal groves; and the underside of the male conductor having a curved apophysis.

[4] As of 2018[update], the World Spider Catalog recognizes the following nine species:[1] Jonathan A. Coddington, a biologist at the National Museum of Natural History, circumscribed the genus Plato in a 1986 revision of the family Theridiosomatidae.

[2] André Lopez at the Centre national de la recherche scientifique described P. juberthiei in 1996,[8] and Pedro H. Prete and colleagues at the Instituto Butantan described the three species P. novalima, P. ferriferus, and P. striatus in 2018.

[2] Coddington placed Plato in a new subfamily Platoninae, alongside the genus Chthonos.