蛛形纲

蛛形纲; 化石时期：437–0 Ma PreЄ Є O S D C P T J K Pg N 志留紀－現代
	《自然界的藝術形態》 (1904), 圖版 66: Arachnida
科学分类
界：	动物界 Animalia
门：	节肢动物门 Arthropoda
演化支：	蛛形类 Arachnomorpha
亚门：	螯肢亚门 Chelicerata
演化支：	真螯肢类 Euchelicerata
演化支：	頭胸足類 Prosomapoda
演化支：	平背板類 Planaterga
演化支：	十三腹節類 Dekatriata
演化支：	硬器類 Sclerophorata
纲：	蛛形纲 Arachnida; Cuvier, 1812
目
	見內文

蛛形綱（學名：Arachnida）又名蜘蛛綱，是節肢動物下的一個綱，包括了蜘蛛、蠍子、壁蝨、螨等。蜘蛛、蠍子等常被大眾誤解為昆蟲，雖然同屬節肢動物門，可是它們都獨立於昆蟲綱之外，屬於蛛形綱。蛛形綱動物的特徵是擁有八隻腳，书肺，体内受精，半變態。蛛形綱動物大多在陸地生活，大部分為肉食性。有一些蜘蛛和蠍子有毒，主要用作自衛及捕獵用途，但大部分的蛛形綱都是無毒的。

分類

根據2011年的分類，現時蛛形綱（Arachnida Cuvier, 1812）有大约112,201左右的物種，當中化石種有†1,586，可作以下分類^[3]：

Order 1
- Order 1.1 盲蛛目 Opiliones Sundevall, 1833: (6,519 species, of which †35 species)11
- Order 1.2 蝎目 Scorpiones C.L. Koch, 1851: (2,068 species, of which †121 species)12
跑足亚纲 Dromopoda
- Order 2.1 避日目 Solifugae Sundevall, 1833: (1,116 species, of which †3 species)13
- Order 2.2 拟蝎目 Pseudoscorpiones de Geer, 1778: (3,494 species, of which †40 species)14
Order 3 鬚腳目 Palpigradi Thorell, 1888: (83 species, of which †1 species)15
Order 4 †古怖目 Phalangiotarbida Haase, 1890: (†31 species )16
Order 5 节腹目 Ricinulei Thorell, 1876: (73 species, of which †15 species)17
寄蟎總目 Parasitiformes^[4]
- Order 6.1 節腹蟎目 Opilioacarida Zakhvatkin, 1952: (37 species, of which †2 species)18
- Order 6.2 巨蟎目 Holothyrida Thon, 1905: (27 species)
- Order 6.3 真蜱目 Ixodida Leach, 1815: (896 species, of which †5 species) 19
- Order 6.4 革蟎目 Mesostigmata G. Canestrini, 1891: (11,424 species)
蟎形總目 Acariformes
- Order 7.1 恙螨目 Trombidiformes Reuter, 1909: (25,821 species, of which †24 species)20
- Order 7.2 疥蟎目 Sarcoptiformes Reuter, 1909 (16,412 species, of which †113 species)21
Order 8
- Order 8.1 †角怖目 Trigonotarbida Petrunkevitch, 1949 (†65 species)22
- Order 8.2.1.1 †乌拉尔蛛目 Uraraneida Selden & Shear in Selden et al., 2008 (†3 species)23
- Order 8.2.1.2 蜘蛛目 Araneae Clerck, 1757: (43,579 species, of which †1,106 species)24
- Order 8.2.2.1 †聯足目 Haptopoda Pocock, 1911 (†1 species)25
无鞭目 Amblypygi
有鞭目 Thelyphonida
裂盾目 Schizomida

参考文献

^ Dunlop, J.A. A trigonotarbid arachnid from the Upper Silurian of Shropshire (PDF). Palaeontology. September 1996, 39 (3): 605–614 [2008-10-12].
^ Andrew J. Wendruff; Loren E. Babcock; Christian S. Wirkner; Joanne Kluessendorf; Donald G. Mikulic. A Silurian ancestral scorpion with fossilised internal anatomy illustrating a pathway to arachnid terrestrialisation. Scientific Reports. 2020, 10: Article number 14. doi:10.1038/s41598-019-56010-z.
^ Zhang, Zhi-Qiang. Phylum Arthropoda von Siebold, 1848 (PDF). Zhang, Z.-Q. (编). Animal biodiversity: An outline of higher-level classification and survey of taxonomic richness (PDF). Magnolia Press. 2011: 123–128. ISBN 978-1-86977-850-7. ISSN 1175-5334 （英语）. |journal=被忽略 (帮助); |issue=被忽略 (帮助)
^ FRÉDÉRIC BEAULIEU, ASHLEY P.G. DOWLING, HANS KLOMPEN, GILBERTO J. DE MORAES & DAVID EVANS WALTER. Superorder Parasitiformes Reuter, 1909 (PDF). Zhang, Z.-Q. (编). Animal biodiversity: An outline of higher-level classification and survey of taxonomic richness (PDF). Magnolia Press. 2011: 123–128. ISBN 978-1-86977-850-7. ISSN 1175-5334 （英语）. |journal=被忽略 (帮助); |issue=被忽略 (帮助)

[1] Dunlop, J.A. A trigonotarbid arachnid from the Upper Silurian of Shropshire (PDF). Palaeontology. September 1996, 39 (3): 605–614 [2008-10-12].

[2] Andrew J. Wendruff; Loren E. Babcock; Christian S. Wirkner; Joanne Kluessendorf; Donald G. Mikulic. A Silurian ancestral scorpion with fossilised internal anatomy illustrating a pathway to arachnid terrestrialisation. Scientific Reports. 2020, 10: Article number 14. doi:10.1038/s41598-019-56010-z.

[Zootaxa_Arachnida-3] Zhang, Zhi-Qiang. Phylum Arthropoda von Siebold, 1848 (PDF). Zhang, Z.-Q. (编). Animal biodiversity: An outline of higher-level classification and survey of taxonomic richness (PDF). Magnolia Press. 2011: 123–128. ISBN 978-1-86977-850-7. ISSN 1175-5334 （英语）. |journal=被忽略 (帮助); |issue=被忽略 (帮助)

[Zootaxa_Parasitiformes-4] FRÉDÉRIC BEAULIEU, ASHLEY P.G. DOWLING, HANS KLOMPEN, GILBERTO J. DE MORAES & DAVID EVANS WALTER. Superorder Parasitiformes Reuter, 1909 (PDF). Zhang, Z.-Q. (编). Animal biodiversity: An outline of higher-level classification and survey of taxonomic richness (PDF). Magnolia Press. 2011: 123–128. ISBN 978-1-86977-850-7. ISSN 1175-5334 （英语）. |journal=被忽略 (帮助); |issue=被忽略 (帮助)

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