Corystidae is a

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

crab Crabs are decapod crustaceans of the infraorder Brachyura (meaning "short tailed" in Greek language, Greek), which typically have a very short projecting tail-like abdomen#Arthropoda, abdomen, usually hidden entirely under the Thorax (arthropo ...

s, in its own superfamily, Corystoidea. It includes what was once thought to be the oldest

Eubrachyura Eubrachyura is a group of decapod crustaceans ( ranked as a "section") comprising the more derived crabs. It is divided into two subsections, based on the position of the genital openings in the two sexes. In the Heterotremata, the openings are o ...

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

, '' Hebertides jurassica'', thought to be dating from the

Bathonian In the geologic timescale the Bathonian is an age (geology), age and stage (stratigraphy), stage of the Middle Jurassic. It lasted from approximately 168.2 ±1.2 annum, Ma to around 165.3 ±1.1 Ma (million years ago). The Bathonian Age succeeds ...

(

Middle Jurassic The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relativel ...

); the species was subsequently reinterpreted as being Cenozoic in age. Corystidae contains ten extant and five extinct species in eight genera: *''

Corystes ''Corystes cassivelaunus'', the masked crab, helmet crab or sand crab, is a burrowing crab of the North Atlantic and North Sea from Portugal to Norway, which also occurs in the Mediterranean Sea. It may grow up to long (carapace length). The na ...

'' Bosc, 1802 *'' Corystites'' Lőrenthey, in Lőrenthey & Beurlen, 1929 *'' Gomeza'' Gray, 1831 *'' Gomezinus'' † Collins, Lee & Noad, 2003 *'' Harenacorystes'' † Van Bakel, Jagt, Artal & Fraaije, 2009 *'' Hebertides'' † Guinot, De Angeli & Garassino, 2007 *'' Jonas'' Hombron & Jacquinot, 1846 *'' Micromithrax'' † Noetling, 1881

References

Crabs Extant Miocene first appearances Decapod families Taxa named by George Samouelle {{Corystoidea-stub