Known as the "red-crested tree rat",[REF] this species was originally described as Isothrix rufodorsalis by American biologist Joel Asaph Allen in 1899, and was transferred to genus Diplomys in 1935 by George Henry Hamilton Tate [REF].
The genus name Santamartamys comes from "Santa Marta", part of the name of the location where the specimens were found, and mys, meaning "mouse" [REF].