Grundulus is an unusual genus of characins - small relatives of the tetras - adapted to a habitat almost no other characiform occupies: cold, high-elevation Andean lakes and rivers of Colombia and Ecuador. The atlas' 3 species, including the guapucha (G. bogotensis) and the La Cocha tetra (G. cochae), are known from waters such as the Bogotá savanna drainage and Lake San Pablo/La Cocha, far outside the warm lowland rivers where most characins live; sizes across the genus span a wide range, from under 1 in to nearly 3 in.
The guapucha in particular has long been an important small food fish for communities around Bogotá, though populations have declined with water pollution, habitat modification and competition from introduced trout and other non-native fish - a decline reflected in the genus' mixed IUCN picture of Least Concern, Near Threatened and not-yet-evaluated assessments. Grundulus has essentially no presence in the ornamental aquarium trade; its interest is regional-food and scientific rather than hobbyist, given how narrowly its cold-water Andean habitat is defined.