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Species Sergiolus montanus

ground spider - Sergiolus montanus which spider ? - Sergiolus montanus Adult female - Sergiolus montanus - female Adult female - Sergiolus montanus - female Sergiolus? - Sergiolus montanus spider id - Sergiolus montanus Mouse Spider? Fantastic abdominal markings. - Sergiolus montanus ground spider - Sergiolus montanus
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynae)
Family Gnaphosidae (Ground Spiders)
Genus Sergiolus
Species montanus (Sergiolus montanus)
Synonyms and other taxonomic changes

previously Poecilochroa montana
There appears to be quite a bit of variation in the abdominal patterning of this species. A microscopic exam of the spider's genitalia is typically necessary for accurate identification.

"...specimens of the widespread species S. montanus are usually colored much like those of northern S. bicolor, but individuals with a light cephalothorax and appendages and more extensive light markings on the abdominal dorsum are known from Oregon, Idaho, Utah, Colorado, and California (where they become proportionately more common toward the southern end of the state)." (Platnick & Shadab 1981)

Example from California (a female):

Examples from Washington (male on left, female on right):

Example from Alaska (a female):


Southernmost Alaska to New Brunswick, south to South Carolina and to Baja California (Norte), Mexico.
See Also
Very similar to other species of Sergiolus; a microscopic exam of genitalia is required for clear identification.
Print References
~ Platnick, N. I. & C. D. Dondale, 1992. The Insects and Arachnids of Canada, Part 19. The ground spiders of Canada and Alaska (Araneae: Gnaphosidae). Research Branch, Agriculture Canada, Publ. 1875: 1-297, PAGE 233. (free download of full monograph from here:

~Platnick, N. I. & M. U. Shadab, 1981e. A revision of the spider genus Sergiolus (Araneae, Gnaphosidae). American Museum Novitates 2717: 1-41, PAGE 28. (full text available here:
Internet References
~ - Image from WA.