The percichthydos are an exclusive family of the South hemisphere. The investigators have not agreed themselves as far as the number of species, although in general three species are recognized: perca small mouth Percichthys trout, perca great mouth Percichthys colhuapensis, and perca espinuda Percichthys altispinnis. In Argentina they are mainly in the introduced salmónidos south and Whose sharing the habitat with, with those who it occupies he himself ecological niche. Nevertheless perca has some adaptive advantages, that have not allowed him to survive the competition of a so efficient pregiver and it even inhabits atmospheres in which the salmónidos ones find resistance environmental. Perca, although promotes some streams for its reproduction, are not to him necessary. It can make egg-layings in the coast of the lakes or lagoons. On the other hand their oxygen requirements are smaller and tolerates high temperatures but. Sometimes it shares the atmosphere with pejerreyes.

They are fish of the evolutionary point of view, but advanced that the salmónidos ones. They are of golden brown color with dark spots but, that can vary according to the atmosphere. They have two dorsal fins with radios, in the one of ahead very thorny, and the very near pelvic fins escapulares and, that allows a capable swimming him. They have gregarious habits but that the salmónidos ones, specially in its youthful stages. It is common to observe shoals of fish in the borders, being looked for pleasant temperatures but.

Although it does not have the combat efficiency characteristics that display the salmónidos ones, does not stop being very attractive, taking any type from decoy.