Pseudotepuibasis gen. nov. is erected for P. garrisoni sp. nov. from the Colombian Amazon (December 2015, Caquetá Department, Solano Municipality, Araracuara, Guacamayo Guard, -72.2497, -0.6308, L. Pérez leg.). Male and female of this new genus are described and illustrated, cerci of male with a ventrobasal spur for which it is considered in the tribe Teinobasini, close to Tepuibasis De Marmels, 2007 and Austrotepuibasis Machado Lencioni, 2011, by its color pattern and cerci morphology; and close to Leptobasis Selys, 1877 and Mesoleptobasis Sjöstedt, 1918, by its genital ligula. Some notable characters of Pseudotepuibasis are a chitinized spine-like process directed posteriorly on the genital ligula, male cerci with chitinized median tooth, and thoracic color pattern.