The abyssal halosaur (Halosauropsis macrochir) is a species of bottom-dwelling, deep-sea fish in the family Halosauridae that is found in all oceans at depths of 1100 to 3500 meters.[1] It is the only member of its genus.[2]
Abyssal halosaur can reach total length of at least and weight in excess of . Berstad et al.[1] could not sex fish smaller than 25 cm, giving an indication about length at maturation. Abyssal halosaur are long-lived, with maximum reported age of 36 years, although individuals sampled on the Mid-Atlantic Ridge were mostly <20 years. It appears to be an opportunistic feeder, mostly taking epibenthos and small fish.[1]