Squat lobsters are dorsoventrally flattened crustaceans with long tails held curled beneath the cephalothorax. They are found in the two superfamilies Galatheoidea and Chirostyloidea, which form part of the decapod infraorder Anomura, alongside groups including the hermit crabs and mole crabs. They are distributed worldwide in the oceans, and occur from near the surface to deep sea hydrothermal vents, with one species occupying caves above sea level. More than 900 species have been described, in around 60 genera. Some species form dense aggregations, either on the sea floor or in the water column, and a small number are commercially fished.
Squat lobster
Squat lobsters can form dense aggregations.
Porcelain crabs, like Neopetrolisthes maculatus, are closely related to squat lobsters.
Dorsal (left) and ventral (right) views of the holotype of Kiwa puravida (Kiwaidae); two pereiopods have broken off on the animal's left side.
The Galatheoidea are a superfamily of decapod crustaceans comprising the porcelain crabs and some squat lobsters. Squat lobsters within the three families of the superfamily Chirostyloidea are not closely related to the squat lobsters within the Galatheoidea. The fossil record of the superfamily extends back to the Middle Jurassic genus Palaeomunidopsis.
Image: Porcelain crab Nick Hobgood
Image: Three toothed squat lobster, Munidopsis tridentata
