Front half of body and head (including pectoral and pelvic fins) roughly diamond shaped and greatly flattened; with a distinct neck between the pectorals; head oval, relatively narrow behind; distance between nostrils distinctly less than that between eyes; nostril barbell narrow, notched and convex; eyes relatively small (6.3 times in space between them) on top of head, with prominent spiracles behind them; mouth at front; pectoral and pelvic fins greatly enlarged; dorsal fins small, about equal sized, situated near tail fin; lower lobe of tail larger; denticles on lower surface almost entirely covering the pectoral and pelvic fins, with a transverse band on chest, a large patch on the abdomen and almost entirely covering the underside of the tail. Holotype with heavy thorns on snout, between eyes and spiracles; a double row of large hooked thorns down midback and between dorsal fins; large thorns on front edge of pectorals.
Grey to grey-brown, mottled and blotched with olive; irregular dusky areas on tail and dorsal fins; lower surface white.
Reaches 113 cm.
On sandy bottoms.
Depth range 3-200m.
A basically temperate species that ranges from Costa Rica to Chile.