Ancistrocheirus lesueurii is of moderate size (25 cm ML) and occupies tropical and subtropical waters of the world's oceans at mesopelagic depths. Adults may be associated with the ocean floor over the slope (Nesis, 1982/7). They bear hooks on the arms and tentacles and have large sagittate fins. Photophores have a distinctive arrangement and appearance. Those on the ventral surface of the head and mantle occur in two very different size catagories.

Brief diagnosis:

A member of the enoploteuthid families ...

• with numerous, small integumental photophores, including photophores on the tentacles but without photophores on the eyeballs or viscera.