Colossal Squid

The heaviest known invertebrate, with eyes the size of dinner plates/Deep Sea & Ocean Life

The colossal squid (Mesonychoteuthis hamiltoni) is the heaviest known living invertebrate, reaching up to 14 meters in length and 495 kilograms in mass. Its eyes are the largest of any known animal at 27 centimeters in diameter -- roughly the size of a dinner plate -- allowing it to detect bioluminescent prey in the near-total darkness of the deep ocean. Unlike the giant squid's sucker-lined tentacles, the colossal squid's tentacles are armed with sharp, swiveling hooks. Very few intact specimens have been recovered, meaning most of what we know comes from pieces found in the stomachs of sperm whales.