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Species Castianeira longipalpa

BG1171 D1387 - Castianeira longipalpa - female Probable C. longipalpa - adult dorsal - Castianeira longipalpa - male Ant Mimic Sac Spider, Castianeira longipalpa - Castianeira longipalpa Castianeira longipalpa? - Castianeira longipalpa - female Castianeira longipalpa - female Pennsylvania Spider for ID - Castianeira longipalpa Ground Sac Spider - Castianeira longipalpa - female Castianeira? - Castianeira longipalpa - male
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynae)
Family Corinnidae (Antmimics and Ground Sac Spiders)
Genus Castianeira
Species longipalpa (Castianeira longipalpa)
Synonyms and other taxonomic changes
Castianeira longipalpus (wrong gender)
Juvenile male

Mature Male

Mature Female

Ventral spination on tibias I and II
Kaston's how to know the spiders tells the difference between Castianeira and Micaria as
- The well marked thoracic groove in Castianeira.
- Tibiae I & II have two or three pairs of ventral spines in Castianeira
Castianeira longipalpa vs. C. variata
Kevin Pfeiffer comments here: Castianiera cf. longipalpa "Species closely resembles C. variata, from which it can be distinguished only by the genitalia characters". (Kaston)

There are no entries under C. variata and no mention of this on the info page for C. longipalpa. I'm thinking all the entries for C. longipalpa, that have not been positively ID'd, should be placed in a C. longipalpa group page. My experience with spider ID is pretty limited so rather than make any changes, I thought I'd mention this in the forums. ~ Contributed by Steve Nanz on 20 July, 2011 - 2:50am

This species is similar in general appearance to Castianeira longipalpus. It differs at sight in having the posterior tibiae marked with distinct basal and distal yellow annulae (rings)**. Carapace dark reddish brown to nearly black with thin white hairs, darker on sides. (1)

** We have not been able to see the yellow rings in photos of live Castianeira variata. At this point we are assuming we can't use this as a reliable field marking to distinguish C. variata from C. longipalpus.

Egg sacs are white and disc-like.(2)
See Also
Print References
Spiders of the Eastern US, Howell and Jenkins, page 265
Works Cited
1.New American spiders of the Clubionidae
W.J. Gertsch. 1942. The American Museum of Natural History; No. 1195.
2.The Spider Subfamily Castianeirinae of North and Central America
J. Reiskind. 1969. Bull. Mus. of Comp. Zool. Vol 138: 163-325.