Species: Mustelus sinusmexicanus, Gulf Smoothhound, Gulf Smoothhound Shark

Mustelus sinusmexicanus Heemstra, 1997

Gulf Smoothhound, Gulf Smoothhound Shark

Elongate, slender body, with its ventral surface flattened; a low pointed skin ridge along top; head short, flattened on top, with thin-tipped snout; snout moderately short, 4.8-6.3% of TL; eyes close-set, moderately large, diameter 1.9-3.1% of TL, oval, with nictitating lower eyelids; spiracles small; nostrils widely separated; mouth broad; labial furrows of upper jaw longer than lower; teeth small, low, in rows or mosaic or pavement pattern, cutting edge with pointed, relatively high crown; five gill slits, last two above pectoral fin; first dorsal taller than second, entirely before pelvics, both with a rounded tips, a concave rear edge and a sharply pointed rear tip; anal fin origin under middle of second dorsal fin; pectoral fins broad, rear edge straight; tail fin slightly raised above body, its tip with a straight edge, subterminal notch present, bottom lobe expanded, rounded; dermal denticles on flank mainly with 3 points.

Top grey to grey-brown, bottom light colored, young may have dusky spots on tips of dorsal fin and caudal fin.

Size: 140 cm.

Habitat: offshore continental shelf and upper slope.

Depth: 20-250 m, usually 42-91 m.

The Gulf of Mexico.