无螯下目

无螯下目; 化石时期：晚侏罗世 – 现在 PreЄ Є O S D C P T J K Pg N
	叶形幼体是无螯下目的典型特征
科学分类
界：	动物界 Animalia
门：	节肢动物门 Arthropoda
亚门：	甲壳亚门 Crustacea
纲：	软甲纲 Malacostraca
目：	十足目 Decapoda
亚目：	腹胚亚目 Pleocyemata
下目：	无螯下目 Achelata; Scholtz & Richter, 1995
科
	见正文

无螯下目（Achelata），也称无螯虾下目，是十足目抱卵亚目下的一个下目。

描述

无螯下目得名于其下的虾没有螯这一事实，“Achelata”来自希腊语，其中α-即a-为“没有”之意，χηλή即chela为“螯”之意。它们拥有扩大的触须，幼体则为特殊的叶形幼体。^[2]

分类

无螯下目包含龙虾科和蝉虾科这两个现存科，^[3] 另外还有坎虾科和三脊虾科这两个已灭绝科。^[1]

龙虾科 Palinuridae Latreille, 1802
蝉虾科 Scyllaridae Latreille, 1825
†坎虾科（英语：Cancrinos） Cancrinos Beurlen, 1930
†三脊虾科（英语：Tricarina）? Tricarina Feldmann et al., 2007

无螯下目下的现存物种

龙虾科的棘刺龙虾

蝉虾科的Scyllarides latus

两个现存科的化石记录都可以追溯到白垩纪。^[4]^[5] 另外两个化石科都只有一个属，^[6] 其中坎虾科生活于侏罗纪至白垩纪之间。^[5] 也有人认为无螯下目的化石记录可以追溯到3亿4100万年前。^[7]

参考资料

^ ^1.0 ^1.1 Sammy De Grave, N. Dean Pentcheff, Shane T. Ahyong; et al. A classification of living and fossil genera of decapod crustaceans (PDF). Raffles Bulletin of Zoology. 2009,. Suppl. 21: 1–109 [2013-04-23]. （原始内容存档 (PDF)于2011-06-06）.
^ Gerhard Scholtz & Stefan Richter. Phylogenetic systematics of the reptantian Decapoda (Crustacea, Malacostraca) (PDF). Zoological Journal of the Linnean Society. 1995, 113 (3): 289–328 [2013-04-23]. doi:10.1006/zjls.1995.0011. （原始内容存档 (PDF)于2020-10-25）.
^ Ferran Palero, Keith A. Crandall, Pere Abelló, Enrique Macpherson & Marta Pascual. Phylogenetic relationships between spiny, slipper and coral lobsters (Crustacea, Decapoda, Achelata). Molecular Phylogenetics and Evolution. 2009, 50 (1): 152–162. PMID 18957325. doi:10.1016/j.ympev.2008.10.003.
^ Francisco J. Vega, Pedro García-Barrera, María del Carmen Perrilliat, Marco A. Coutiño & Ricardo Mariño-Pérez. El Espinal, a new plattenkalk facies locality from the Lower Cretaceous Sierra Madre Formation, Chiapas, southeastern Mexico (PDF). Revista Mexicana de Ciencias Geológicas. 2006, 23 (3): 323–333 [2013-04-23]. （原始内容存档 (PDF)于2017-08-13）.
^ ^5.0 ^5.1 Joachim T. Haug, Carolin Haug, Dieter Waloszek, Andreas Maas, Matthias Wulf & Günter Schweigert. Development in Mesozoic scyllarids and implications for the evolution of Achelata (Reptantia, Decapoda, Crustacea) (PDF). Palaeodiversity. 2009, 2: 97–110 [2013-04-23]. （原始内容存档 (PDF)于2021-03-09）.
^ Rodney M. Feldmann, Ali Kolahdouz, Bijan Biranvand & Guenter Schweigert. A new family, genus, and species of lobster (Decapoda: Achelata) from the Gadvan Formation (Early Cretaceous) of Iran (PDF). Journal of Paleontology. 2007, 81 (2): 405–407 [2013-04-23]. doi:10.1666/0022-3360(2007)81[405:ANFGAS]2.0.CO;2. （原始内容 (PDF)存档于2016-03-04）.
^ Keith A. Crandall, Megan L. Porter & Marcos Pérez-Losada. Crabs, shrimps and lobsters (Decapoda). S. Blair Hedges & Sudhir Kumar (编). The Timetree of Life. Oxford University Press. 2009: 293–297. ISBN 978-0-19-160898-8.

外部链接

维基共享资源上的相关多媒体资源：无螯下目

[Grave-1] 1.0 ^1.1 Sammy De Grave, N. Dean Pentcheff, Shane T. Ahyong; et al. A classification of living and fossil genera of decapod crustaceans (PDF). Raffles Bulletin of Zoology. 2009,. Suppl. 21: 1–109 [2013-04-23]. （原始内容存档 (PDF)于2011-06-06）.

[2] Gerhard Scholtz & Stefan Richter. Phylogenetic systematics of the reptantian Decapoda (Crustacea, Malacostraca) (PDF). Zoological Journal of the Linnean Society. 1995, 113 (3): 289–328 [2013-04-23]. doi:10.1006/zjls.1995.0011. （原始内容存档 (PDF)于2020-10-25）.

[3] Ferran Palero, Keith A. Crandall, Pere Abelló, Enrique Macpherson & Marta Pascual. Phylogenetic relationships between spiny, slipper and coral lobsters (Crustacea, Decapoda, Achelata). Molecular Phylogenetics and Evolution. 2009, 50 (1): 152–162. PMID 18957325. doi:10.1016/j.ympev.2008.10.003.

[4] Francisco J. Vega, Pedro García-Barrera, María del Carmen Perrilliat, Marco A. Coutiño & Ricardo Mariño-Pérez. El Espinal, a new plattenkalk facies locality from the Lower Cretaceous Sierra Madre Formation, Chiapas, southeastern Mexico (PDF). Revista Mexicana de Ciencias Geológicas. 2006, 23 (3): 323–333 [2013-04-23]. （原始内容存档 (PDF)于2017-08-13）.

[Haug-5] 5.0 ^5.1 Joachim T. Haug, Carolin Haug, Dieter Waloszek, Andreas Maas, Matthias Wulf & Günter Schweigert. Development in Mesozoic scyllarids and implications for the evolution of Achelata (Reptantia, Decapoda, Crustacea) (PDF). Palaeodiversity. 2009, 2: 97–110 [2013-04-23]. （原始内容存档 (PDF)于2021-03-09）.

[6] Rodney M. Feldmann, Ali Kolahdouz, Bijan Biranvand & Guenter Schweigert. A new family, genus, and species of lobster (Decapoda: Achelata) from the Gadvan Formation (Early Cretaceous) of Iran (PDF). Journal of Paleontology. 2007, 81 (2): 405–407 [2013-04-23]. doi:10.1666/0022-3360(2007)81[405:ANFGAS]2.0.CO;2. （原始内容 (PDF)存档于2016-03-04）.

[7] Keith A. Crandall, Megan L. Porter & Marcos Pérez-Losada. Crabs, shrimps and lobsters (Decapoda). S. Blair Hedges & Sudhir Kumar (编). The Timetree of Life. Oxford University Press. 2009: 293–297. ISBN 978-0-19-160898-8.

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