Microlophichthys microlophus

Microlophichthys microlophus is, like the other deep sea anglerfishes, sexually dimorphic. The metamorphosed females are characterised by having naked skin, without spinules. They further have spines on the sphenotic bone and the rear margin of the operculim is deeply incised. The pectoral fins have a lobe which is shorter than the longest rays of that fin and wide. There is a spine at the symphysis of the lower jaw and the dentary bones are convex at the lower margin of the symphyses. The fin rays in the caudal fin have no internal pigmentation, the black skin of the caudal peduncle extends past the caudal fin base. The short illicium emerges on the snout between the frontal bones, the escal bulb has a length which is greater than half of the length of the illicium and the mouth extends past the eye.^[6] The metamorphosed males share many of the characteristics of the metamorphosed females but they have no teeth in their jaws, the upper dentary bone has an undetermined number, some being fused, of denticles which are long and irregularly curved while the lower dentary bone has 8 low and robust denticle on a row with the outer denticle slightly offset.^[7] The maximum published total length is for a female of M. microlophus and was 11.8 cm (4.6 in),^[8] while males vary in total length between 6.8 and 17 mm (0.27 and 0.67 in).^[7]

Microlophichthys microlophus is found in the tropical and subtropical paortions of the Atlantic, Indian and Pacific Oceans.^[8] Although it has been recorded as far north as the subarctic Atlantic Ocean off Greenland.^[9] These anglerfishes are bathypelagic and are found at depths between 800 and 2,000 m (2,600 and 6,600 ft).^[8]