| Common names: grunt (English), roncacho (Espanol), corocoro (Espanol), ronco (Espanol) |
Pomadasys bayanus Jordan & Evermann, 1898
Purple-mouth grunt, Freshwater grunt
Elongate, strongly compressed; mouth long, reaches under center of eye, inside not red, lips thin; chin with 2 pores at front and 2 inside hole behind, plus a longitudinal groove; preopercle weakly or not serrated, ventral serrations not forward pointing; dorsal fin XII-XIII, 12, moderately notched; anal III, 7, second anal spine very long and stout, its length about two times eye diameter or more; pectoral fins relatively short, not reaching tips of depressed pelvic fins; pelvics short, not reaching anus (except in small juveniles); no scales on soft dorsal and anal fins; 50-51 pored lateral line scales; 8 oblique rows of scales between lateral line and origin of dorsal fin.
Silvery, with an orange tint on sides; fins orangish; juvenile with wavy stripes.
Size: grows to 36 cm.
Habitat: tolerates salinities between 20-30 ppt, but travels considerable distances up fast moving rivers.
Depth: 0-10 m.
Southern Baja to Peru.