Facing full into the camera, this is a zoea larva of a fighting or swimming crab. The British swimming crab used to be called Portunus but now is Necora puber. Compound eyes are placed one each side of its head. Spines are protective against predators. Also known as fighting crabs, portunids have a very sharp spur on the inner side of their pincers. This, they very efficiently swipe across any attacker that approaches from the front, and can inflict a very painful wound to a careless human who fails to lift it from behind, where this spur cannot reach.
Lizard Island, Australia (1998)
Nikon F301 | Custom Optics | Fuji Velvia