Scientific Illustration

rhamphotheca:

Diversity of Squid

The giant squid may be the biggest, but it’s not the only squid in the sea. Scientists estimate there are about 500 species of squid. Some are surprisingly tiny—only about 2.5 cm (1 in) in length. Others are impressively large. There are three species of giant squid (Architeuthis), the largest of which may grow up to 16 m (50 ft) long. And there are other large squid as well—including one known as the colossal squid (Mesonychoteuthis hamiltoni). Despite these vast differences in size, all squids share certain features: long, cylindrical bodies, usually with eight arms and two long feeding tentacles; and two fins that help them balance and maneuver as they swim.

(image: Kim Moeller/Smithsonian Institution)