Echimys is a genus of the spiny rats family, the Echimyidae. Members of this genus are collectively called spiny tree-rats.
The genus name Echimys, and also its synonym Echinomys, derive from the two Ancient Greek words, meaning "hedgehog", and, meaning "mouse, rat".[1] [2]
The genus contains three extant species
Members of the genera Callistomys, Makalata, Pattonomys, and Phyllomys were all formerly considered part of the genus Echimys.
Echimys is the sister genus to Phyllomys, and then to Makalata. These taxa are closely related to the genera Pattonomys and Toromys.In turn, these five genera share phylogenetic affinities with a clade containing the bamboo rats Dactylomys, Olallamys, Kannabateomys together with Diplomys and Santamartamys.