The bulldog goodeid, Alloophorus robustus, is a large goodeid endemic to Mexico where it is found in the Lerma River basin and other Pacific slope river basins. This species grows to a length of 12 centimetres (4.7 in) TL. It is the only known species in its genus.This species is found in the aquarium trade where it is hard to maintain due to the predatory nature of the adults. They have to be fed a diet of small fish and watch the water quality as with all goodeids.