Family: GINGLYMOSTOMATIDAE, Nurse Sharks
Diagnostic features of nurse sharks (which reach ~ 3 m) include a short, wide, blunt snout; oval eyes, behind mouth; a pair of large barbels below the snout; a groove between each nasal opening and the corner of the mouth; mouth small, transverse, opens a little under snout; 5 gill slits, the last two very close together and above the pectoral fin; two relatively close-set dorsal fins of about equal size on the rear half of the body; a relatively short, strongly asymmetric tail with almost no lower lobe; no keels on tail base.
Nurse sharks are found on reefs, usually close to shore. The sole W Atlantic representative of this family, Ginglymostoma cirratum, is ovoviviparous, with young that are nourished mainly by yolk while in the uterus; litters of 20-30 young are produced. Nurse sharks, which are nocturnally active, cruise around the bottom in search of food with their mouth and barbels close to the substrate. Prey (fishes, crabs, shrimps, lobsters, other crustaceans, and cephalopods) are ingested with a powerful sucking action.
A circumglobal family with 3 subtropical to tropical genera and 3 species; one species occurs in our region and in the east and West Atlantic.