Species: Ginglymostoma cirratum, Nurse Shark

Ginglymostoma cirratum (Bonnaterre, 1788)

Nurse Shark

Head broad and flattened; snout broad, rounded; nostrils with large barbels; eyes small, oval, behind the mouth; mouth small, transverse, opens a little under snout; teeth small, multicusped; five small gill arches, last two close together and over pectoral fin; fins blunt and rounded; two large dorsal fins, second dorsal ~½ size of first, base of first one over base of pelvics; tail asymmetrical, lower lobe hardly developed.

Yellow brown to grey brown; young with small dark spots and obscure saddle markings on back.

Size: to ~ 300 (possibly 430) cm.

Lives around reefs, mangroves, and sand flats.

Depth range: 0-130 m, usually nearshore.

The E and W Atlantic; in the W Atlantic from Rhode Island to S Brazil.

Note: Compared to its East Pacific sister species, G unami, the Atlantic species G cirratum has: (i) the 1st dorsal fin origin further back relative to the pelvic fins (ii) the pelvic fins not reaching as far towards the 2nd dorsal fin; (iii) the two dorsal fins are further apart; (iv) the 2nd dorsal fin does not reach as close to the tail fin; (v) the anal fin does not reach as close to the base of the tail fin; (vi) the pelvic fins are further from the anal fin; (vii) the body is more slender; (viii) the teeth have fewer secondary cusplets (2-3 on each side vs 5-6), which are pointed rather than blunt; and (ix) the skin denticles are narrower and with fewer keels.