Stomias boa ferox

Stomias boa ferox has an elongated body and small head;[6] it is up to 30 cm (0.98 ft) in length, black underneath and iridescent silver on its flanks, with a barbel that has a pale stem, dark spot at base of bulb and three blackish filaments.[7][8] It has six rows of hexagonal areas above a lateral series of large photophores.[9] The dorsal and anal fins are opposite each other, just anterior to the caudal fin.[10] It can be distinguished from the S. boa boa subspecies by its larger number of photophores.[11]

The subspecies name ferox means "wild, ferocious." It is sometimes called dragon-boa, dragonfish or boa dragonfish,[12][13] but those names are equally applied to Stomias boa as a species, or the S. boa boa subspecies. In Icelandic it is marsnákur ("sea snake") and in Norwegian storkjeft ("big jaw").[14][15]

Stomias boa ferox is mesopelagic and bathypelagic, living at depths of 20–800 m (66–2,625 ft), concentrated in the north Atlantic.[16][17]

Stomias boa ferox eats midwater fishes and crustaceans; it rises to near the surface to feed at night.[8] It positions itself horizontally in the water column with pelvic and pectoral fins spread wide and barbel pointing forward.[18]

Stomias boa ferox is oviparous.[19][20]