Poromitra crassiceps (Günther, 1878) .

Crested Bigscale or Crested Ridgehead. To 19 cm (7.5 in) SL (Kotlyar, 2009). Atlantic, Pacific, and Southern Oceans (Fricke et al. 2020); western Pacific Ocean north to Japan (Fujii in Masuda et al. 1984), and Russian north-western Pacific Ocean (Orlov and Tokranov 2019), to southern Bering Sea, and Gulf of Alaska (Mecklenburg et al. 2002), to Chile (Pequeño 1989). Primarily mesopelagic and bathypelagic; depth: 0–4,000 m (13,120 ft) (Orlov and Tokranov 2019). Considered a separate species, Poromitra rugosa (Chapman, 1939), by some authors. However, we follow Robertson et al. (2017) and consider this P. crassiceps . This species was split into many taxa by Kotlyar (2009).