Young and Roper, 1969
Mantle widely-conical, not tapering into tail, its anterior margin without finger-like flaps. Head wider than mantle, eyes in juveniles protruding anteriorly and sideways. Fin wide, transverse-oval, its length in juveniles approx. 60% ML, in adults equal to ML. Arms rather short, commonly broken off at ends. Tentacles very long, club wide, with prominent aboral keel. Central suckers (4-5 pairs in mid-part of club) very large, globular. Funnel cartilage elongate-triangular with rather shallow pit located near short side of triangle and one narrow anterior groove. Mantle cartilage: a low crest with knob on end. Gladius thick, paddle-like, with short rachis and parallel sides, without conus.
A large unpaired photophore on outer mantle surface ventrally near end of body, some others around iris. No photophores on anterior mantle, head, or ink sac.
Juveniles may be distinguished by very large fin, large central club suckers, and tail photophore. Known ML up to 13 cm.
Another species, Discoteuthis laciniosa Young and Roper, 1969, differs in having 2 pairs of photophores on the ventro-anterior mantle margin and on the head between the bases of 3rd and 4th arms, a series of finger-like flaps on anterior mantle margin, no tail photophore, funnel cartilage with 2 grooves, large central club suckers flattened.