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TaxonomyBrowse
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Genus Micaria

Orange County Ground Spider - Micaria pasadena ant-mimic spider - Micaria longipes - male Spider egg sac on maple leaf - Micaria Golden Ant-Mimic spider - Micaria Micaria - Micaria pulicaria - male Spider - Micaria - female Spider - Micaria - female Micaria female - Micaria - female
Classification
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Chelicerata (Chelicerates)
Class Arachnida (Arachnids)
Order Araneae (Spiders)
Infraorder Araneomorphae (True Spiders)
No Taxon (Entelegynes )
Family Gnaphosidae (Ground Spiders)
Genus Micaria
Numbers
41 species in BugGuide's range (North America north of Mexico).
Identification
Gertsch 1942
M. alberta
- Carapace golden brown with golden hairs, midline with a row of black setae.
- Legs dark with pale stripe.
- Abdomen gray with a pair of white transverse bars above the pedicel and a larger pair at the middle of the dorsum
- irridescent scales some golden but most silvery
M. gosiuta - UT (similar to alberta but has more widely separated posterior eyes)
- Abdomen with basal pair of white patches above the pedicel, and a larger pair at the middle of the dorsum
- iridescent scales evenly golden
M. riggsi - CT, TN
- Carapace dark reddish brown
- Legs orange
- Abdomen black with black iridescent scales
- sides with golden iridescent scales
M. apacheana - AZ & ?
- Carapace yellow brown dusky radiating lines & scattered yellow scales
- Legs yellowish brown, front femora dusky on sides last two with distinct black side bands (creating pale stripes)
- Dorsum of the abdomen with basal and larger median paired white spots
Range
Canadian Micaria - Platnick & Dondale, 1992

More specific range information to be added when resources/time allows.

M. aenea - Holarctic
M. alpina - Holarctic
M. capistrano - USA, Mexico
M. cimarron - USA
M. coloradensis - USA, Canada
M. constricta - Holarctic
M. delicatula - USA
M. deserticola - USA, Mexico
M. elizabethae - USA, Canada
M. emertoni - North America
M. foxi - USA, Canada
M. gertschi - USA, Canada
M. gosiuta - USA, Canada
M. icenoglei - USA
M. idana - USA, Canada
M. imperiosa - USA, Mexico
M. jeanae - USA, Mexico
M. langtry - USA
lassena - USA
M. laticeps - USA, Canada
M. longipes - BC to New Brunswick, south to AZ & Mexico
M. longispina - USA, Canada
M. medica - USA, Canada
M. mormon - North America
M. nanella - USA, Mexico
M. nye - USA, Mexico
M. otero - USA
M. palliditarsa - USA, Mexico
M. palma - USA
M. pasadena - USA, Mexico
M. porta - USA, Mexico
M. pulicaria - Alaska to Newfoundland, south to CA & TX
M. punctata - USA
M. riggsi - South BC to Mass. south to AZ & TN
M. rossica - Holarctic
M. seminola - USA
M. triangulosa - USA
M. tripunctata - Alaska to Manitoba
M. utahna - USA
M. vinnula - USA
Remarks
In Micaria PER is rarely procurved... usually straight. (Castianeira the PER are slightly to moderately procurved.)

Notes on separating Micaria from Castianeira from Rod Crawford:

Micaria is a gnaphosid although very atypical of the family. It has endites that are crossed by a depression or "valley" between the front and back end of each endite

Micaria has the spinnerets cylindrical (although they are not wide apart like other gnaphosids) while in [members of Corinnidae] the spinnerets would be tapered toward the ends

Micaria: carapace standard pear-shape as in


abdomen covered (or partly so) with translucent iridescent scales color pattern often, though not always, includes chevron-shapes somewhat smaller than Castianeira spinnerets cylindrical and endites with depression (= Gnaphosidae)

Castianeira:
narrowing in front of carapace reduced; narrowing in rear increased

No iridescent scales
Color pattern either strictly transverse or with longitudinal parts, nothing chevron-like somewhat larger than Micaria without gnaphosid family characteristics

Notes from Resources

According to SONA
- all gnaphosids (Micaria) have irregularly shaped PMEs, Castianeira are round
- Castianeira as not having a constricted abdomen

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

Also, Reiskind (1969), page 164, says the posterior median eyes in Micaria are oval or oblong, which will help to distinguish it from Castianeira (Corinnidae), whose PME are circular.
Print References
Platnick & Shadab 1988. A revision of the American spiders of the genus Micaria (Araneae, Gnaphosidae). American Museum Novitates; no. 2916. http://hdl.handle.net/2246/5164