Aspidophoroides monopterygius; Print; The Alligatorfish (Aspidophoroides monopterygius; also known commonly as the Aleutian alligatorfish and the Atlantic alligatorfish) is a fish in the family Agonidae (poachers). It was described by Marcus Elieser Bloch in 1786. It is a marine; temperate water-dwelling fish which is known from the northwestern Atlantic Ocean; including western Greenland; Labrador; Canada; and Cape Cod; Massachusetts; USA. It dwells at a depth range of 0-695 metres; most often around 60-150 m; and inhabits sand and mud bottoms mostly on the lower continental shelf all year. It prefers a temperature range of -1.07 to 2.52 癈. Males can reach a maximum total length of 22 centimetres; but more commonly reach a TL of 14.2 cm.; 1700-1880