Carlhubbsia is a small genus of livebearing fish in family Poeciliidae, native to Atlantic-slope streams and rivers of southern Mexico and Guatemala. The atlas covers 2 species, 2–2.5 in, both slender-bodied fish of the Yucatan and Usumacinta region typical of the gambusia-like poeciliid build. The genus name honors Carl L. Hubbs, the American ichthyologist whose work described and revised much of the poeciliid family.
Hobby profile is modest - Carlhubbsia is more a livebearer-specialist genus than a fish routinely seen in general aquarium retail. Both atlas species, C. kidderi and C. stuarti, are currently assessed Least Concern, and one carries a CARES conservation priority listing here. As with other small poeciliids, care would follow the broad livebearer pattern of live birth, omnivorous feeding, and modest space needs, though detailed husbandry notes specific to the genus are sparse outside specialist circles.