Profundulus is a genus of Middle American killifish, the namesake genus of the family Profundulidae, native to montane streams and rivers of southern Mexico and northern Central America. The atlas's records span Mexico, Guatemala, Belize, Honduras, and El Salvador. Unlike many killifish known from temporary pools, Profundulus species are non-annual, living year-round in flowing, often cool highland streams rather than seasonal habitats, and the four species in the atlas are modest in size, from about 3 in as adults.
Profundulus is a genus of scientific rather than aquarium interest — it is essentially absent from the ornamental fish trade, and reliable species-specific husbandry guidance is sparse. What stands out instead is a troubling conservation profile: none of the atlas's four species — the Guatemalan killifish (P. guatemalensis), Chiapas killifish (P. hildebrandi), P. kreiseri, and Oaxacan killifish (P. oaxacae) — carries a Least Concern rating, with two rated Vulnerable, one Endangered, and one Data Deficient. That pattern fits montane stream fish confined to small highland drainages, where deforestation, water extraction, and stream degradation can affect an entire population at once.