Species: Sphyrna tiburo, Bonnethead shark, Common bonnethead shark, the Bonnethead

Sphyrna tiburo (Linnaeus, 1758)

Bonnethead shark, Common bonnethead shark

A small hammerhead shark with a very narrow, rounded shovel-shaped head, without the prominent lateral-blade extensions of other hammerheads; width of head 19-25% of TL; front margin of head broadly convex and without indentations; teeth smooth; front teeth blade-like, with 1 short, stout point, rear teeth are enlarged keeled molars; lower front teeth straight, upper front teeth oblique & deeply notched on rear side;  five gill slits, last one over pectoral; first dorsal fin moderately large and erect, its rear margin concave, its origin behind the pectoral rear tip, its free rear tip not reaching over pelvic fins; second dorsal fin base about half length of anal fin base; origin of second dorsal fin above middle of anal fin; anal fin rear edge shallowly concave; transverse pit above tail base crescent shaped, a pit below tail base; tail fin strongly asymmetrical, notched under tip of top lobe, large lower lobe.