Symphurus callopterus Munroe & Mahadeva, 1989. Chocolate Tonguefish or Feather Tonguefish. To 40 cm (15.7 in) TL (Vargas et al. 2020). Pacific coast of southern Baja California (Munroe et al. in Fischer et al. 1995) to northern Peru (Chirichigno and Vélez 1998), including lower Gulf of California (Munroe et al. in Fischer et al. 1995). Benthic; depth: 18–636 m (59–2,086 ft) (min.: Munroe et al. in Fischer et al. 1995; max.: Nakaya et al. 2009).