Species: Mustelus canis, Dusky Smoothhound Shark, Smooth Dogfish, Smooth Dogfish Shark

Mustelus canis (Mitchill, 1815)

Smooth Dogfish, Dusky Smooth-hound Shark, Smooth Dogfish Shark

Elongate and slender, relatively flat on ventral surface; a low pointed skin ridge on midline of back; head flattened on top; snout relatively short (5-5.8% of TL); eyes oval, moderately large (2.2-2.4% of TL), close together, with longitudinal nictitating eyelid; spiracles small but prominent; space between nostrils broad, 2.7-3.6% of TL; mouth relatively broad, 4.7-6.8% of TL; labial furrows longer on upper jaw longer than lower, 1.6-2.7% of TL; teeth small, oval, low, in several rows in a mosaic or pavement pattern, cutting edges bluntly rounded; 5 gill slits, last two over pectoral fin; two dorsal fins, both with tips rounded, and deeply concave rear margins and acute rear corners, first dorsal higher than second, origin over back of pectoral base; anal fin origin under mid-point of second dorsal; pectoral fins broad; tail fin low, blunt tip, top lobe with a well developed sub-terminal notch, ventral lobe small, rounded; dermal denticles on flank elongate, single point.

Back olive or slaty grey, variable with substrate; belly yellowish or whitish grey; posterior margin of first dorsal fin whitish in young.

Size: 152 cm.

Habitat: dwells on bottom in coastal waters, generally on muddy bottoms.

Depth: 7-808 m.

Canada to Uruguay.

Note: Two subspecies are recognized, M. c. canis from the continental shore and M. c. insularis from the Greater and Lesser Antilles.