Anomura (sometimes Anomala) is a group of decapodcrustaceans, including hermit crabs and others. Although the names of many anomurans include the word crab, all true crabs are in the sister group to the Anomura, the Brachyura (the two groups together form the clade Meiura).[1]
The name Anomura derives from an old classification in which reptant decapods were divided into Macrura (long-tailed), Brachyura (short-tailed) and Anomura (differently-tailed). The alternative name Anomala reflects the unusual variety of forms in this group; whereas all crabs share some obvious similarities, the various groups of anomurans are quite dissimilar.[2]
The group has been moulded by several instances of carcinisation – the development of a crab-like body form.[3] Thus, the king crabs (Lithodidae), porcelain crabs (Porcellanidae) and hairy stone crab (Lomisidae) are all separate instances of carcinisation.[3]
As decapods (meaning ten-legged), anomurans have ten pereiopods, but the last pair of these is reduced in size, and often hidden inside the gill chamber (under the carapace) to be used for cleaning the gills.[4][2] Since this arrangement is very rare in true crabs (for example, the small family Hexapodidae),[5] a "crab" with only eight visible pereiopods is generally an anomuran.[2]
Some of the internal relationships within Anomura can be shown in the cladogram below, which shows Hippidae as sister to Paguroidea, and resolves Parapaguridae outside of Paguroidea:[6]
^Gerhard Scholtz; Stefan Richter (1995). "Phylogenetic systematics of the reptantian Decapoda (Crustacea, Malacostraca)" (PDF). Zoological Journal of the Linnean Society. 113 (3): 289–328. doi:10.1111/j.1096-3642.1995.tb00936.x.
^ abcGary Poore (2004). "Anomura – hermit crabs, porcelain crabs and squat lobsters". Marine Decapod Crustacea of Southern Australia: a Guide to Identification. CSIRO Publishing. pp. 215–287. ISBN978-0-643-09925-8.
^ abcShane T. Ahyong; Kareen E. Schnabel; Elizabeth W. Maas (2009). "Anomuran phylogeny: new insights from molecular data". In Joel W. Martin; Keith A. Crandall; Darryl L. Felder (eds.). Decapod Crustacean Phylogenetics. Crustacean issues. Vol. 18. CRC Press. pp. 399–414. doi:10.1201/9781420092592-c20. ISBN978-1-4200-9258-5.
^Jonas Keiler; Stefan Richter (2011). "Morphological diversity of setae on the grooming legs in Anomala (Decapoda: Reptantia) revealed by scanning electron microscopy". Zoologischer Anzeiger. 250 (4): 343–366. doi:10.1016/j.jcz.2011.04.004.
^Carrie E. Schweitzer; Rodney M. Feldmann (2001). "Differentiation of the fossil Hexapodidae Miers, 1886 (Decapoda: Brachyura) from similar forms" (PDF). Journal of Paleontology. 75 (2): 330–345. doi:10.1666/0022-3360(2001)075<0330:DOTFHM>2.0.CO;2. S2CID 85997166.
^ abWolfe, 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.
^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.
^ abJérôme Chablais; Rodney M. Feldmann; Carrie E. Schweitzer (2011). "A new Triassic decapod, Platykotta akaina, from the Arabian shelf of the northern United Arab Emirates: earliest occurrence of the Anomura" (PDF). Paläontologische Zeitschrift. 85: 93–102. doi:10.1007/s12542-010-0080-y. S2CID 5612385.
^K. E. Schnabel; S. T. Ahyong; E. W. Maas (2011). "Galatheoidea are not monophyletic – molecular and morphological phylogeny of the squat lobsters (Decapoda: Anomura) with recognition of a new superfamily". Molecular Phylogenetics and Evolution. 58 (2): 157–168. doi:10.1016/j.ympev.2010.11.011. PMID 21095236.
anomura, sometimes, anomala, group, decapod, crustaceans, including, hermit, crabs, others, although, names, many, anomurans, include, word, crab, true, crabs, sister, group, brachyura, groups, together, form, clade, meiura, temporal, range, norian, recent, pr. Anomura sometimes Anomala is a group of decapod crustaceans including hermit crabs and others Although the names of many anomurans include the word crab all true crabs are in the sister group to the Anomura the Brachyura the two groups together form the clade Meiura 1 AnomuraTemporal range Norian Recent PreꞒ Ꞓ O S D C P T J K Pg NThe hermit crab Dardanus megistosScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ArthropodaClass MalacostracaOrder DecapodaSuborder Pleocyemata unranked ReptantiaInfraorder AnomuraMacleay 1838SuperfamiliesAegloidea Chirostyloidea Eocarcinoidea Galatheoidea Hippoidea Lithodoidea Lomisoidea Paguroidea Contents 1 Description 2 Evolution 3 Classification 4 References 5 External linksDescription editThe name Anomura derives from an old classification in which reptant decapods were divided into Macrura long tailed Brachyura short tailed and Anomura differently tailed The alternative name Anomala reflects the unusual variety of forms in this group whereas all crabs share some obvious similarities the various groups of anomurans are quite dissimilar 2 The group has been moulded by several instances of carcinisation the development of a crab like body form 3 Thus the king crabs Lithodidae porcelain crabs Porcellanidae and hairy stone crab Lomisidae are all separate instances of carcinisation 3 As decapods meaning ten legged anomurans have ten pereiopods but the last pair of these is reduced in size and often hidden inside the gill chamber under the carapace to be used for cleaning the gills 4 2 Since this arrangement is very rare in true crabs for example the small family Hexapodidae 5 a crab with only eight visible pereiopods is generally an anomuran 2 Evolution editThe infraorder Anomura belongs to the group Reptantia which consists of the walking crawling decapods lobsters and crabs There is wide acceptance from morphological and molecular data that Anomura and Brachyura true crabs are sister taxa together making up the clade Meiura 3 The cladogram below shows Anomura s placement within the larger order Decapoda from analysis by Wolfe et al 2019 6 Decapoda Dendrobranchiata prawns nbsp Pleocyemata Stenopodidea boxer shrimp nbsp Procarididea Caridea 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 Meiura Anomura hermit crabs and others nbsp Brachyura crabs nbsp crawling walking decapods Some of the internal relationships within Anomura can be shown in the cladogram below which shows Hippidae as sister to Paguroidea and resolves Parapaguridae outside of Paguroidea 6 Anomura Porcellanidae porcelain crabs Munididae squat lobsters Parapaguridae deep water sea anemone hermit crabs Eumunididae squat lobster like Hippidae mole crabs or sand crabs Paguroidea Lithodidae king crabs Paguridae hermit crabs Diogenidae left handed hermit crabs Coenobitidae terrestrial hermit crabs Classification editThe infraorder Anomura contained seven extant superfamilies 7 8 9 10 Superfamily Members Families PhotoAegloidea Aegla Aeglidae nbsp Aegla sp Chirostyloidea squat lobsters ChirostylidaeEumunididaeKiwaidae nbsp Eumunida picta Eocarcinoidea Eocarcinus Platykotta Eocarcinidae PlatykottidaeGalatheoidea squat lobstersporcelain crabs GalatheidaeMunididaeMunidopsidaePorcellanidae Retrorsichelidae nbsp Munidopsis serricornis Munidopsidae Hippoidea mole crabsor sand crabs AlbuneidaeBlepharipodidaeHippidae nbsp Blepharipoda occidentalis Blepharipodidae Lithodoidea king crabs HapalogastridaeLithodidae nbsp Lithodes santolla Lithodidae Lomisoidea hairy stone crab Lomisidae nbsp Lomis hirta Lomisidae Paguroidea hermit crabscoconut crab CoenobitidaeDiogenidaePaguridaeParapaguridaeParapylochelidaePylochelidaePylojacquesidae nbsp Coenobita clypeatus Coenobitidae The oldest fossil attributed to Anomura is Platykotta from the Norian Rhaetian Late Triassic Period in the United Arab Emirates 8 References edit Gerhard Scholtz Stefan Richter 1995 Phylogenetic systematics of the reptantian Decapoda Crustacea Malacostraca PDF Zoological Journal of the Linnean Society 113 3 289 328 doi 10 1111 j 1096 3642 1995 tb00936 x a b c Gary Poore 2004 Anomura hermit crabs porcelain crabs and squat lobsters Marine Decapod Crustacea of Southern Australia a Guide to Identification CSIRO Publishing pp 215 287 ISBN 978 0 643 09925 8 a b c Shane T Ahyong Kareen E Schnabel Elizabeth W Maas 2009 Anomuran phylogeny new insights from molecular data In Joel W Martin Keith A Crandall Darryl L Felder eds Decapod Crustacean Phylogenetics Crustacean issues Vol 18 CRC Press pp 399 414 doi 10 1201 9781420092592 c20 ISBN 978 1 4200 9258 5 Jonas Keiler Stefan Richter 2011 Morphological diversity of setae on the grooming legs in Anomala Decapoda Reptantia revealed by scanning electron microscopy Zoologischer Anzeiger 250 4 343 366 doi 10 1016 j jcz 2011 04 004 Carrie E Schweitzer Rodney M Feldmann 2001 Differentiation of the fossil Hexapodidae Miers 1886 Decapoda Brachyura from similar forms PDF Journal of Paleontology 75 2 330 345 doi 10 1666 0022 3360 2001 075 lt 0330 DOTFHM gt 2 0 CO 2 S2CID 85997166 a b 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 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 a b Jerome Chablais Rodney M Feldmann Carrie E Schweitzer 2011 A new Triassic decapod Platykotta akaina from the Arabian shelf of the northern United Arab Emirates earliest occurrence of the Anomura PDF Palaontologische Zeitschrift 85 93 102 doi 10 1007 s12542 010 0080 y S2CID 5612385 K E Schnabel S T Ahyong E W Maas 2011 Galatheoidea are not monophyletic molecular and morphological phylogeny of the squat lobsters Decapoda Anomura with recognition of a new superfamily Molecular Phylogenetics and Evolution 58 2 157 168 doi 10 1016 j ympev 2010 11 011 PMID 21095236 WoRMS 2018 Anomura WoRMS World Register of Marine Species Retrieved 2018 09 28 External links edit nbsp Crustaceans portal nbsp Arthropods portal nbsp Media related to Anomura at Wikimedia Commons nbsp Data related to Anomura at Wikispecies Retrieved from https en wikipedia org w index php title Anomura amp oldid 1174632239, wikipedia, wiki, book, books, library,
