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Home » Guide » Arthropods (Arthropoda) » Chelicerates (Chelicerata) » Arachnids (Arachnida)

Class Arachnida - Arachnids

Black and Yellow Argiope - Argiope aurantia - female Harvestman - Leiobunum Pseudoscorpion Hubbardiidae - Hubbardia pentapeltis Windscorpion - Eremocosta Scorpion - Uroctonites montereus Ixodes scapularis Say - Ixodes scapularis - female Erythraeidae - Callidosoma
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Numbers
Worldwide: (1)
12 orders
450 families
75,500 species

Orders:
Amblypygi - Tailless Whipscorpions
Araneae - Spiders
Uropygi - Whipscorpions
Opiliones - Harvestmen
Palpigradi - Microscorpions
Pseudoscorpiones - Pseudoscorpions
Ricinulei - Hooded Tickspiders
Schizomida - Short-tailed Whipscorpions
Scorpiones - Scorpions
Solifugae - Windscorpions
Subclass Acari - Mites and Ticks
-Superorder Parasitiformes
Ixodida - Ticks
Mesostigmata
Opilioacarida
-Superorder Acariformes
Astigmata
Endeostigmata
Oribatida
Trombidiformes
Identification
One or two body parts
Four pairs of legs (usually - although immature ticks, for example, can have three pairs of legs)
No antennae
Internet References
Information on the Arachnids
Common Names of Arachnids 2003 Fifth Edition - The American Arachnological Society; Committee on Common Names of Arachnids
Works Cited
1.Animal: The Definitive Visual Guide to the World's Wildlife
Don E. Wilson, David Burnie. 2001. Dorling Kindersley Publishing.
Contributed by Troy Bartlett on 31 January, 2004 - 4:47pm
Additional contributions by Phillip Harpootlian, Lynette Elliott, Jeff Hollenbeck, Bbarnd, Chuck Entz, Ted Kropiewnicki, kschnei, KenW, Edward Ruden, Blocky
Last updated 3 March, 2019 - 9:48pm

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