Identification, Images, & Information
For Insects, Spiders & Their Kin
For the United States & Canada
 

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Calendar

Upcoming Events

National Moth Week was July 19-27, and the Summer 2025 gathering in Louisiana, July 19-27

Photos of insects and people from the 2024 BugGuide gathering in Idaho July 24-27

Moth submissions from National Moth Week 2024

Photos of insects and people from the 2022 BugGuide gathering in New Mexico, July 20-24

Photos of insects and people from the Spring 2021 gathering in Louisiana, April 28-May 2

Photos of insects and people from the 2019 gathering in Louisiana, July 25-27

Class Arachnida - Arachnids

Representative Images

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) 13‒15 orders, 450 families, >110,000 named species (of which ~a half are spiders)
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

Four pairs of legs (immature ticks can have three, some mites just two); no antennae

Internet References

Common names of Arachnids

Works Cited

1.Nat. Hist. Museum Bern (2024) World Arachnida Catalog
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, v belov, KenW, Edward Ruden, Blocky
Last updated 24 December, 2024 - 2:27pm

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