Head about as wide as deep, depressed anteriorly; middle of length of head behind anterior border of pupil. Snout short and broadly protruding, with acute rostral spine; lateral margin strongly curved. Teeth in premaxillaries conical, not arrow-shaped, in 5 to 8 irregularly oblique series, forming a wide band as a whole, those of outer series evenly enlarged and widely spaced. Scales on body large, hexagonal, and rather deciduous; spinules stout and pungent, forming 4-11 divergent ridges, last spinule of each series more or less projecting beyond apical margin of scales. Scales on head coarser, less imbricated, and more adhesive than those on body; scales 7 or 8 in a longitudinal series on nasal crest, with spinous rows radiating in all directions from center of each scale, spinules never on ridges but independently rising from surface of scales. This median series of scales followed on each side by a single series of less-modified scales. Nasal fossa naked. No naked area on dorsal surface of snout, but a naked groove extending from base of rostral spine backward to interorbital space alongside median rostral series of scales. Underside of head, including mandibular regions and branchiostegal membranes, entirely naked. Vent immediately before anal fin and preceded by a luminous organ of short type (Ref. 54421).