Scolichthys is a small genus of livebearing fish in family Poeciliidae, confined to the freshwater drainages of Guatemala. The atlas covers 2 species, both small - 1.5–2 in - with the slim body and upturned, insect-picking mouth typical of surface-oriented poeciliids. Like all poeciliids, females carry and give live birth to developed fry rather than laying eggs, and the genus's entire known range sits within a single Central American country, a narrow footprint that makes it vulnerable to any one watershed's decline.
Scolichthys has never been a hobby staple; it is known mainly to livebearer specialists and to the conservation-aquarium community, reflected in the atlas's CARES listing for one of its two species. The IUCN picture is a genuine concern rather than an artifact of under-study - one species is assessed Vulnerable and the other Data Deficient, consistent with small-range Central American freshwater fish under pressure from habitat degradation and water use. For a keeper, that conservation weight matters more than any care reputation: these are fish worth maintaining as an assurance population, not casual community-tank picks.