The Decapoda or decapods (literally "ten-footed") are an order of crustaceans within the class Malacostraca, including many familiar groups, including crabs, lobsters, crayfish, shrimp, and prawns. Most decapods are scavengers. The order is estimated to contain nearly 15,000 species in around 2,700 genera, with around 3,300 fossil species.[1] Nearly half of these species are crabs, with the shrimp (about 3,000 species) and Anomura including hermit crabs, porcelain crabs, squat lobsters (about 2500 species) making up the bulk of the remainder.[1] The earliest fossils of the group date to the Devonian.
Decapods can have as many as 38 appendages,[2] arranged in one pair per body segment. As the name Decapoda (from the Greekδέκα, deca-, "ten", and πούς / ποδός, -pod, "foot") implies, ten of these appendages are considered legs. They are the pereiopods, found on the last five thoracic segments.[2] In many decapods, one pair of these "legs" has enlarged pincers, called chelae, with the legs being called chelipeds. In front of the pereiopods are three pairs of maxillipeds that function as feeding appendages. The head has five pairs of appendages, including mouthparts, antennae, and antennules. There are five more pairs of appendages on the abdomen. They are called pleopods. There is one final pair called uropods, which, with the telson, form the tail fan.[2]
A 2019 molecular clock analysis suggested decapods originated in the Late Ordovician around 455 million years ago, with the Dendrobranchiata (prawns) being the first group to diverge. The remaining group, called Pleocyemata, then diverged between the swimming shrimp groupings and the crawling/walking group called Reptantia, consisting of lobsters and crabs. High species diversification can be traced to the Jurassic and Cretaceous periods, which coincides with the rise and spread of modern coral reefs, a key habitat for the decapods.[3] Despite the inferred early origin, the oldest fossils of the group such as Palaeopalaemon only date to the Late Devonian.[4]
The cladogram below shows the internal relationships of Decapoda, from analysis by Wolfe et al. (2019).[3]
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. The Dendrobranchiata consist of prawns, including many species colloquially referred to as "shrimp", such as the "white shrimp", Litopenaeus setiferus. The Pleocyemata include the remaining groups, including "true shrimp".[5] Those groups that usually walk rather than swim (Pleocyemata, excluding Stenopodidea and Caridea) form a clade called Reptantia.[6]
This classification to the level of superfamilies follows De Grave et al.[1]
^ abcSammy De Grave; N. Dean Pentcheff; Shane T. Ahyong; et al. (2009). (PDF). Raffles Bulletin of Zoology. Suppl. 21: 1–109. Archived from the original (PDF) on 2011-06-06.
^ abc. University of Bristol: Decapoda characters. Archived from the original on 10 November 2013. Retrieved 11 December 2017.
^ abcWolfe, Joanna M.; Breinholt, Jesse W.; Crandall, Keith A.; Lemmon, Alan R.; Lemmon, Emily Moriarty; Timm, Laura E.; et al. (24 April 2019). "A phylogenomic framework, evolutionary timeline, and genomic resources for comparative studies of decapod crustaceans". Proceedings of the Royal Society B. 286 (1901). doi:10.1098/rspb.2019.0079. PMC6501934. PMID 31014217.
^Gueriau, Pierre; Rak, Štěpán; Broda, Krzysztof; Kumpan, Tomáš; Viktorýn, Tomáš; Valach, Petr; Zatoń, Michał; Charbonnier, Sylvain; Luque, Javier (2020-10-25). "Exceptional Late Devonian arthropods document the origin of decapod crustaceans". doi:10.1101/2020.10.23.352971. S2CID 226229304. {{cite journal}}: Cite journal requires |journal= (help)
^Elena Mente (2008). Reproductive Biology of Crustaceans: Case Studies of Decapod Crustaceans. Science Publishers. p. 16. ISBN978-1-57808-529-3.
^G. Scholtz; S. Richter (1995). "Phylogenetic systematics of the reptantian Decapoda (Crustacea, Malacostraca)". Zoological Journal of the Linnean Society. 113 (3): 289–328. doi:10.1006/zjls.1995.0011.
decapoda, other, uses, decapod, decapod, disambiguation, confused, with, decapodiformes, decapods, literally, footed, order, crustaceans, within, class, malacostraca, including, many, familiar, groups, including, crabs, lobsters, crayfish, shrimp, prawns, most. For other uses of decapod see Decapod disambiguation Not to be confused with Decapodiformes The Decapoda or decapods literally ten footed are an order of crustaceans within the class Malacostraca including many familiar groups including crabs lobsters crayfish shrimp and prawns Most decapods are scavengers The order is estimated to contain nearly 15 000 species in around 2 700 genera with around 3 300 fossil species 1 Nearly half of these species are crabs with the shrimp about 3 000 species and Anomura including hermit crabs porcelain crabs squat lobsters about 2500 species making up the bulk of the remainder 1 The earliest fossils of the group date to the Devonian DecapodaTemporal range Devonian recent PreꞒ Ꞓ O S D C P T J K Pg NFrom left to right Grapsus grapsus Brachyura Coconut crab Anomura Lysmata amboinensis Caridea Homarus gammarus Astacidea Scientific classificationDomain EukaryotaKingdom AnimaliaPhylum ArthropodaClass MalacostracaSuperorder EucaridaOrder DecapodaLatreille 1802SubordersDendrobranchiataPleocyemata See text for superfamilies Contents 1 Anatomy 2 Evolution 3 Classification 4 See also 5 References 6 External linksAnatomy EditMain article Decapod anatomy Decapods can have as many as 38 appendages 2 arranged in one pair per body segment As the name Decapoda from the Greek deka deca ten and poys podos pod foot implies ten of these appendages are considered legs They are the pereiopods found on the last five thoracic segments 2 In many decapods one pair of these legs has enlarged pincers called chelae with the legs being called chelipeds In front of the pereiopods are three pairs of maxillipeds that function as feeding appendages The head has five pairs of appendages including mouthparts antennae and antennules There are five more pairs of appendages on the abdomen They are called pleopods There is one final pair called uropods which with the telson form the tail fan 2 nbsp Decapoda from Ernst Haeckel s Kunstformen der Natur 1904Evolution EditA 2019 molecular clock analysis suggested decapods originated in the Late Ordovician around 455 million years ago with the Dendrobranchiata prawns being the first group to diverge The remaining group called Pleocyemata then diverged between the swimming shrimp groupings and the crawling walking group called Reptantia consisting of lobsters and crabs High species diversification can be traced to the Jurassic and Cretaceous periods which coincides with the rise and spread of modern coral reefs a key habitat for the decapods 3 Despite the inferred early origin the oldest fossils of the group such as Palaeopalaemon only date to the Late Devonian 4 The cladogram below shows the internal relationships of Decapoda from analysis by Wolfe et al 2019 3 Decapoda Dendrobranchiata prawns nbsp Pleocyemata Stenopodidea boxer shrimp nbsp ProcaridideaCaridea true shrimp nbsp Reptantia Achelata spiny lobsters slipper lobsters nbsp Polychelida benthic crustaceans Astacidea lobsters crayfish nbsp Axiidea mud shrimp ghost shrimp or burrowing shrimp Gebiidea mud lobsters and mud shrimp Anomura hermit crabs and others nbsp Brachyura crabs nbsp crawling walking decapods In the cladogram above the clade Glypheidea is excluded due to lack of sufficient DNA evidence but is likely the sister clade to Polychelida within Reptantia 3 Classification EditClassification 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 The Dendrobranchiata consist of prawns including many species colloquially referred to as shrimp such as the white shrimp Litopenaeus setiferus The Pleocyemata include the remaining groups including true shrimp 5 Those groups that usually walk rather than swim Pleocyemata excluding Stenopodidea and Caridea form a clade called Reptantia 6 This classification to the level of superfamilies follows De Grave et al 1 nbsp Whiteleg shrimp Litopenaeus vannamei Dendrobranchiata Penaeoidea nbsp Heterocarpus ensifer Caridea Pandaloidea nbsp Austropotamobius pallipes Astacidea Astacoidea nbsp Upogebia deltaura Gebiidea Upogebiidae nbsp California spiny lobster Panulirus interruptus Achelata Palinuridae nbsp Polycheles sculptus Polychelida Polychelidae nbsp Australian land hermit crab Coenobita variabilis Anomura Paguroidea nbsp Atlantic blue crab Callinectes sapidus Brachyura Portunoidea Order Decapoda Latreille 1802 Suborder Dendrobranchiata Bate 1888 Penaeoidea Rafinesque 1815 Sergestoidea Dana 1852 Suborder Pleocyemata Burkenroad 1963 Infraorder Stenopodidea Bate 1888 Infraorder Caridea Dana 1852 Procaridoidea Chace amp Manning 1972 Galatheacaridoidea Vereshchaka 1997 Pasiphaeoidea Dana 1852 Oplophoroidea Dana 1852 Atyoidea De Haan 1849 Bresilioidea Calman 1896 Nematocarcinoidea Smith 1884 Psalidopodoidea Wood 1874 Stylodactyloidea Bate 1888 Campylonotoidea Sollaud 1913 Palaemonoidea Rafinesque 1815 Alpheoidea Rafinesque 1815 Processoidea Ortmann 1896 Pandaloidea Haworth 1825 Physetocaridoidea Chace 1940 Crangonoidea Haworth 1825 Infraorder Astacidea Latreille 1802 Enoplometopoidea de Saint Laurent 1988 Nephropoidea Dana 1852 Astacoidea Latreille 1802 Parastacoidea Huxley 1879 Infraorder Glypheidea Winckler 1882 Glypheoidea Winckler 1882 Infraorder Axiidea de Saint Laurent 1979b Infraorder Gebiidea de Saint Laurent 1979 Infraorder Achelata Scholtz amp Richter 1995 Infraorder Polychelida Scholtz amp Richter 1995 Infraorder Anomura MacLeay 1838 Aegloidea Dana 1852 Galatheoidea Samouelle 1819 Hippoidea Latreille 1825a Chirostyloidea Ortmann 1892 Lithodoidea Samouelle 1819 Lomisoidea Bouvier 1895 Paguroidea Latreille 1802 Infraorder Brachyura Linnaeus 1758 Section Dromiacea De Haan 1833 Dromioidea De Haan 1833 Homolodromioidea Alcock 1900 Homoloidea De Haan 1839 Section Raninoida De Haan 1839 Section Cyclodorippoida Ortmann 1892 Section Eubrachyura de Saint Laurent 1980 Subsection Heterotremata Guinot 1977 Aethroidea Dana 1851 Bellioidea Dana 1852 Bythograeoidea Williams 1980 Calappoidea De Haan 1833 Cancroidea Latreille 1802 Carpilioidea Ortmann 1893 Cheiragonoidea Ortmann 1893 Corystoidea Samouelle 1819 Dairoidea Serene 1965 Dorippoidea MacLeay 1838 Eriphioidea MacLeay 1838 Gecarcinucoidea Rathbun 1904 Goneplacoidea MacLeay 1838 Hexapodoidea Miers 1886 Leucosioidea Samouelle 1819 Majoidea Samouelle 1819 Orithyioidea Dana 1852c Palicoidea Bouvier 1898 Parthenopoidea MacLeay Pilumnoidea Samouelle 1819 Portunoidea Rafinesque 1815 Potamoidea Ortmann 1896 Pseudothelphusoidea Ortmann 1893 Pseudozioidea Alcock 1898 Retroplumoidea Gill 1894 Trapezioidea Miers 1886 Trichodactyloidea H Milne Edwards 1853 Xanthoidea MacLeay 1838 Subsection Thoracotremata Guinot 1977 Cryptochiroidea Paul son 1875 Grapsoidea MacLeay 1838 Ocypodoidea Rafinesque 1815 Pinnotheroidea De Haan 1833See also Edit nbsp Crustaceans portal nbsp Arthropods portalList of Atlantic decapod species Phylogeny of MalacostracaReferences Edit a b c Sammy De Grave N Dean Pentcheff Shane T Ahyong et al 2009 A classification of living and fossil genera of decapod crustaceans PDF Raffles Bulletin of Zoology Suppl 21 1 109 Archived from the original PDF on 2011 06 06 a b c Decapoda characters and anatomy University of Bristol Decapoda characters Archived from the original on 10 November 2013 Retrieved 11 December 2017 a b c Wolfe Joanna M Breinholt Jesse W Crandall Keith A Lemmon Alan R Lemmon Emily Moriarty Timm Laura E et al 24 April 2019 A phylogenomic framework evolutionary timeline and genomic resources for comparative studies of decapod crustaceans Proceedings of the Royal Society B 286 1901 doi 10 1098 rspb 2019 0079 PMC 6501934 PMID 31014217 Gueriau Pierre Rak Stepan Broda Krzysztof Kumpan Tomas Viktoryn Tomas Valach Petr Zaton Michal Charbonnier Sylvain Luque Javier 2020 10 25 Exceptional Late Devonian arthropods document the origin of decapod crustaceans doi 10 1101 2020 10 23 352971 S2CID 226229304 a href Template Cite journal html title Template Cite journal cite journal a Cite journal requires journal help Elena Mente 2008 Reproductive Biology of Crustaceans Case Studies of Decapod Crustaceans Science Publishers p 16 ISBN 978 1 57808 529 3 G Scholtz S Richter 1995 Phylogenetic systematics of the reptantian Decapoda Crustacea Malacostraca Zoological Journal of the Linnean Society 113 3 289 328 doi 10 1006 zjls 1995 0011 External links Edit nbsp Wikimedia Commons has media related to Decapoda nbsp Data related to Decapoda at Wikispecies Decapod Crustacea Tree of Life page at the Natural History Museum of Los Angeles County Decapoda at Curlie Retrieved from https en wikipedia org w index php title Decapoda amp oldid 1175207118, wikipedia, wiki, book, books, library,
