Bigeye thresher shark

Alopias superciliosus

Length Up to 16 ft, generally under 13 ft
Description Very long tail, almost as long as rest of body; violet-gray dorsally becoming lighter on sides; distinctive v-shaped groove on top of head gives helmet-like appearance
Food Eats squid and bony fishes; stuns prey with tail before feeding
Habitat Pelagic waters and at deep bottom areas, from the surface to depths of over 1,600 ft
Reproduction Aplacental vivipary, embryos feed on eggs in uterus after using up yolk sac; litter size normally 2; size at maturity 9 ft (9-10 yrs) for males, 11 ft (12-13 yrs) for females