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

Family Philodromidae - Running Crab Spiders

Running Crab Spider - Philodromus - male Spider Lunch with the crane fly - Tibellus Running Crab Spider - Philodromus March spider - male running crab spider? - Philodromus - male Shiny Spider - Philodromus marxi Spider
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynes)
Family Philodromidae (Running Crab Spiders)
Explanation of Names
From Greek philodromos (φιλοδρομος)- "lover of the race/course"
Numbers
96 species in 5 genera in our region (1). The majority of the species are in the large genus Philodromus.
Identification
Philodromids tend to have the second pair of legs significantly longer than the first pair, which distinguishes them from the similar Thomisid crab spiders. In addition, thomisids have third and fourth legs that are shorter and more slender than the first two pairs of legs, while philodromid legs are subequal in length.
Internet References
Works Cited
1.Spiders of North America: An Identification Manual
By D. Ubick, P. Paquin, P.E. Cushing and V. Roth (eds)