Suckermouth

In fishes, a suckermouth is a ventrally-oriented (inferior) mouth adapted for grazing on algae and small organisms that grow on submerged objects.

All Loricariidae possess a suckermouth as do the cypriniform algae eaters of the genus Gyrinocheilus and other genera. The 'False Siamensis' (Epalzeorhynchus sp. or Garra taeniata) also has this feature. Three genera in Mochokidae, Atopochilus, Chiloglanis, and Euchilichthys, also possess an oral sucker, formed by the lips and part of the barbels. The Loricariidae and members of the genus Gyrinocheilus are further adapted by having a special opening on the gill cover so that the fish can breathe without using its mouth.