The decapods or Decapoda (literally means "ten footed") are an order of crustaceans within the class Malacostraca, including many familiar groups, such as crayfish, crabs, lobsters, prawns and shrimp. Most decapods are scavengers.
Anatomy
As their name implies, all decapods have ten legs; these are the last five of the eight pairs of thoracic
appendages characteristic of crustaceans. The front three pairs function as mouthparts and are generally referred to as
maxillipeds, the remainder being
pereiopods. In many decapods, however, one pair of legs has enlarged pincers; the
claws are called
chelae, so those legs may be called
chelipeds. Further appendages are found on the abdomen, with each segment capable of carrying a pair of biramous
pleopods, the last of which form part of the tail fan (together with the
telson) and are called
uropods.
Classification
Classification within the order Decapoda depends on the structure of the
gills and legs, and the way in which the
larvae develop, giving rise to two suborders:
Dendrobranchiata and
Pleocyemata. Dendrobranchiata consists of
prawns, including many species colloquially referred to as "shrimp", such as the
Atlantic white shrimp. Pleocyemata includes the remaining groups, including true
shrimp.
The following classification to the level of superfamilies follows Martin and Davis , with some changes based on more recent morphological and molecular studies .
Order Decapoda Latreille, 1802
- Suborder Dendrobranchiata Bate, 1888 — prawns
- Suborder Pleocyemata Burkenroad, 1963
- Infraorder Stenopodidea Claus, 1872
- Infraorder Caridea Dana, 1852 — true shrimp
- Superfamily Procaridoidea Chace & Manning, 1972
- Superfamily Galatheacaridoidea Vereshchaka, 1997
- Superfamily Pasiphaeoidea Dana, 1852
- Superfamily Oplophoroidea Dana, 1852
- Superfamily Atyoidea de Haan, 1849
- Superfamily Bresilioidea Calman, 1896
- Superfamily Nematocarcinoidea Smith, 1884
- Superfamily Psalidopodoidea Wood-Mason & Alcock, 1892
- Superfamily Stylodactyloidea Bate, 1888
- Superfamily Campylonotoidea Sollaud, 1913
- Superfamily Palaemonoidea Rafinesque, 1815
- Superfamily Alpheoidea Rafinesque, 1815
- Superfamily Processoidea Ortmann, 1890
- Superfamily Pandaloidea Haworth, 1825
- Superfamily Crangonoidea Haworth, 1825
- Infraorder Eryonoidea de Haan, 1841
- Infraorder Achelata Scholtz & Richter, 1995
- Infraorder Astacidea Latreille, 1802 - lobsters and crayfish
- Infraorder Thalassinidea Latreille, 1831
- Infraorder Anomura MacLeay, 1838
- Infraorder Brachyura Linnaeus, 1758 — crabs
- Section Dromiacea de Haan, 1833
- Section Eubrachyura de Saint Laurent, 1980
- Superfamily Raninoidea de Haan, 1839
- Superfamily Cyclodorippoidea Ortmann, 1892
- Superfamily Dorippoidea MacLeay, 1838
- Superfamily Calappoidea Milne Edwards, 1837
- Superfamily Leucosioidea Samouelle, 1819
- Superfamily Majoidea Samouelle, 1819
- Superfamily Hymenosomatoidea MacLeay, 1838
- Superfamily Parthenopoidea MacLeay, 1838
- Superfamily Retroplumoidea Gill, 1894
- Superfamily Cancroidea Latreille, 1802
- Superfamily Portunoidea Rafinesque, 1815
- Superfamily Bythograeoidea Williams, 1980
- Superfamily Xanthoidea MacLeay, 1838
- Superfamily Bellioidea Dana, 1852
- Superfamily Potamoidea Ortmann, 1896
- Superfamily Pseudothelphusoidea Ortmann, 1893
- Superfamily Gecarcinucoidea Rathbun, 1904
- Superfamily Cryptochiroidea Paulson, 1875
- Superfamily Pinnotheroidea de Haan, 1833
- Superfamily Ocypodoidea Rafinesque, 1815
- Superfamily Grapsoidea MacLeay, 1838
References
External links