Welcome to the new AntWeb!

We here at AntWeb have been busy working on our newest (and most ambitious) version of the site - and there are lots of great new things! Which means there are lots of changes (don't worry, they're all for the best).

And we've put together a handy little guide to show you all the new features and enhancements - why don't you have a quick look to check out all the new features and enhancements?

No thanks
Current View: Nearctic: Alberta
Cite this page

Citing AntWeb


To cite this page, please use the following:

· For print: . Accessed

· For web:

Species: Formica (rufa-group) obscuripes   Forel, 1886 

Download Data

See Also:

Formica obscuripes_cf

Taxonomic History (provided by Barry Bolton, 2014)

Formica rufa r. obscuripes Forel, 1886b PDF: xxxix (w.) U.S.A. Nearctic. AntCat AntWiki

Taxonomic history

Emery, 1893k PDF: 650 (q.m.); Wheeler & Wheeler, 1953c PDF: 165 (l.); Hung, 1969 PDF: 456 (k.).
Raised to species: Creighton, 1950a PDF: 492.
Senior synonym of Formica aggerans: Forel, 1914c PDF: 619; Creighton, 1940a PDF: 1; of Formica melanotica: Creighton, 1950a PDF: 492.
Material of the unavailable name Formica rubiginosa referred here by Creighton, 1940a PDF: 1.
See also: Weber, 1935 PDF: 165.


NEARCTIC: United States: WA OR CA ID NV UT MT WY* CO NM ND SD WI IL; Canada: British Colombia, Alberta, Saskatchewan, Manitoba, Ontario. *The type specimen was collected in Wyoming. A collection of Formica obscuripes was made at Ft. Davis, TX by an unknown collector on 6Jun1902. Specimen from AMNH collection.


Broad habitat preferences, an incomplete list includes: sagebrush steppe, prairie, hardwood forest, and mixed coniferous forest. This species as currently conceived, besides have broad habitat preferences, has high variability in coloration, from mostly red (black gaster) to almost completely infuscate black (head orange). Like many other Formica, F. obscuripes primarily tends hemipterans on vegetation.


Head as broad as long; scapes not covered in erect setae; setae present on lateral corners of headcapsule; setae present on pronotum, mesonotum and propodeum; erect setae present on femora and on tibiae in addition to ventral double row. Makes more-or-less dome-shaped thatch-mounds of organic debris.
The current concept of F. obscuripes allows for variation in length and density of setae and pubescence on all abovementioned surfaces. In the Great Plains and Pacific Northwest, majors are somewhat infuscated, while minors are completely dark.


Check Alex Wild's determination of some northern California material as F. planipilis. Also note that McIver & Loomis (1993. Insectes Sociaux 40:207-218) record "Formica planipilis" from SNARL, near Mammoth. I think that these two taxa may be conspecific.

Taxonomic Treatment (provided by Plazi)

Specimen Habitat Summary

Found most commonly in these habitats: 12 times found in shrub steppe, 6 times found in conifer forest, 1 times found in sagebrush, 5 times found in aspen forest, 0 times found in Pinyon-cedar woodland, 0 times found in oak woodland, 1 times found in lodgepole pine forest, 0 times found in Shortgrass prairie, 4 times found in sparse conifer woods, 0 times found in Pasture, ...

Collected most commonly using these methods or in the following microhabitats: 83 times search, 0 times Thatched nest, 1 times under rock, 4 times hand collecting, 0 times Roadside, 0 times Thatch nest of pine needles, 0 times Thached nest, 0 times Low thatched nest, 0 times meadow, thatched nest, 0 times Thatched log, 1 times observation, ...

Elevations: collected from 5 - 2896 meters, 1521 meters average

Type specimens: syntype of Formica obscuripes: casent0911081; syntype of Formica rufa obscuriventris melanotica: casent0905698

(-1 examples)

See something amiss? Send us an email.