Author: Cuvier, 1817
Diagnostic Features:
Body very stout. Snout acutely conical, rather long; nostrils more mesial on snout, situated medial to head rim in ventral view; mouth broadly parabolic; teeth narrow and thick, awl-shaped, with narrow smooth-edged, nearly straight cusps and usually well-developed lateral cusplets (except in young below 1 m long); intermediate teeth in upper jaw small, less than half height of upper anteriors. First dorsal origin over or just behind the pectoral insertions, anal origin about under second dorsal origin; small secondary keels present on base of caudal fin just below primary keels.
Remarks:
Specimens and the literature suggest that there are only two species in the genus, with L. philippi from Chile and L. whitleyi from New Zealand and Australia most probably being synonyms of L. nasus. As shown by Bigelow and Schroeder (1948) and Nakaya (1971), L. ditropis is readily separable from L. nasus.