Rhonciscus bayanus (Jordan & Evermann, 1898). Freshwater Grunt or Purplemouth Grunt. To 41 cm (16.1 in) SL (Jiménez Prado et al. 2015). Bahía Magdalena, southern Baja California (Rodríguez-Romero et al. 2011) to Rio Tumbes, Peru (Chirichigno 1974), and at mouth of Gulf of California (Robertson and Allen 2002). Marine, brackish and fresh waters (Jiménez-Prado et al. 2014); depth: 0–10 m (33 ft) (Robertson and Allen 2002). We follow Tavera et al. (2018) in moving Pomadasys bayanus Jordan & Evermann, 1898 to the genus Rhonciscus.