Decapoda

From Includipedia, the inclusionist encyclopedia

For other meanings of decapod, see decapod.

Decapoda

"Decapoda" from Ernst Haeckel's Artforms of Nature, 1904

Kingdom:	Animalia
Phylum:	Arthropoda
Subphylum:	Crustacea
Class:	Malacostraca
Superorder:	Eucarida
Order:	Decapoda Latreille, 1802

Suborders

Dendrobranchiata
Pleocyemata
See text for superfamilies.

The decapods or Decapoda 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.

1 Anatomy
2 Classification
3 References
4 External links

Anatomy

Main article: Decapod 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 ^[1], with some changes based on more recent morphological and molecular studies ^[2]^[3].

Image:Penaeus vannamei 01.jpg

Whiteleg shrimp, Litopenaeus vannamei

Image:Spotted cleaner shrimp.jpg

Spotted cleaner shrimp, Periclimenes yucatanicus

Image:Lobster 300.jpg

California spiny lobster, Panulirus interruptus

Image:Bfgnbigred2.jpg

Australian land hermit crab, Coenobita variabilis

Image:Blue crab on market in Piraeus - Callinectes sapidus Rathbun 20020819-317.jpg

Blue crab, Callinectes sapidus

Image:Lyreidus tridentatus.jpg

Lyreidus tridentatus

Order Decapoda Latreille, 1802

Suborder Dendrobranchiata Bate, 1888 — prawns
- Superfamily Penaeoidea Rafinesque, 1815
- Superfamily Sergestoidea Dana, 1852
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
  - Superfamily Enoplometopoidea de Saint Laurent, 1988
  - Superfamily Glypheoidea Winkler, 1883
  - Superfamily Nephropoidea Dana, 1852
  - Superfamily Astacoidea Latreille, 1802
  - Superfamily Parastacoidea Huxley, 1879
- Infraorder Thalassinidea Latreille, 1831
  - Superfamily Thalassinoidea Latreille, 1831
  - Superfamily Callianassoidea Dana, 1852
  - Superfamily Axioidea Huxley, 1879
- Infraorder Anomura MacLeay, 1838
  - Superfamily Lomisoidea Bouvier, 1895
  - Superfamily Galatheoidea Samouelle, 1819 — squat lobsters
  - Superfamily Hippoidea Latreille, 1825
  - Superfamily Paguroidea Latreille, 1802 — hermit crabs
- Infraorder Brachyura Latreille, 1802 — crabs
  - Section Dromiacea de Haan, 1833
    - Superfamily Homolodromioidea Alcock, 1900
    - Superfamily Dromioidea de Haan, 1833
    - Superfamily Homoloidea de Haan, 1839
  - 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

^ Joel W. Martin and George E. Davis (2001). An Updated Classification of the Recent Crustacea. Natural History Museum of Los Angeles County.
^ Dixon, C. J., F. R. Schram & S. T. Ahyong (2004). A new hypothesis of decapod phylogeny. Crustaceana 76 (8): 935–975.
^ Porter, M. L., M. Pérez-Losada & K. A. Crandall (2005). Model-based multi-locus estimation of decapod phylogeny and divergence times. Molecular Phylogenetics and Evolution 37: 355–369.