An osteological comparison of seven species of silversides that occur from the Patos-Mirim lagoons systems is presented and discussed. Five species inhabit freshwater environments, Odontesthes bonariensis (Valenciennes, 1835), O. humensis De Buen, 1953, O. retropinnis (De Buen, 1953), O. perugiae Evermann & Kendall, 1906, and O. mirinensis Bemvenuti, 1995. The other species, O. incisa (Jenyns, 1842) and O. argentinensis (Valenciennes, 1835), inhabit in coastal and brackish waters.
Atheriniformes; bone feature; morphology; taxonomy