Diagnosed from all its congeners by having a unique pigmentation pattern of body and fins in males consisting of a uniform bluish gray background color on the body that lacks vertical bands, and uniform pigmentation of unpaired fins. Can also be distinguished by the combination of characters associated with reduced squamation in the abdominal, preopercular, and opercular regions. The reduction in the number of scales in the abdomen occurs in three alternative states: completely naked abdomen, only a ventral row of small scales, or just area below pectoral fin without scales (vs. scales always absent in anterior part of the abdomen as in Austrolebias gymnoventris); preopercular region is either completely naked or only has a few scales present in its center (vs. preopercular region always naked as in Austrolebias gymnoventris); and the opercular region is from completely naked to only distal edge naked (vs. only opercular distal edge naked as in Austrolebias gymnoventris). However, in extremely large males (SL > 40 mm) and females (SL > 34 mm), which represent less than 7% of individuals analyzed, scales almost completely cover the preopercular, opercular, and abdominal regions (Ref. 87318).

Description: dorsal-fin rays in males 19-27; in females 15-19; anal-fin rays in males 17-24, in females 14-19; pectoral fin rays 9-14 in males, 10-12 in females;