The genus Erythrolamprus belongs to the subfamily Dipsadinae, which is sometimes referred to as the family Dipsadidae.

Female topotypes had relatively shorter tails.

The belly is black, as indicated by its specific name (from Latin atra (=black) and venter (=belly)).

[1][3] The IUCN did not identify any overt threats affecting E. atraventer, and lists the species as "Least Concern".

It is locally common, e.g., in the Serra do Mar State Park.