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Species Formica obscuripes - Thatching ant

Western Thatching Ant - mound - Formica obscuripes red and black ant - Formica obscuripes black winged ant - Formica obscuripes Ant identification - Formica obscuripes Ant Mound - Formica obscuripes Mound ant - Formica obscuripes Formica neorufubarbis? - Formica obscuripes black ant with orange head - Formica obscuripes
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Hymenoptera (Ants, Bees, Wasps and Sawflies)
No Taxon (Aculeata - Ants, Bees and Stinging Wasps)
Superfamily Formicoidea (Ants)
Family Formicidae (Ants)
Subfamily Formicinae
Tribe Formicini
Genus Formica (Wood ants, mound ants, & field ants)
No Taxon (rufa group)
Species obscuripes (Thatching ant)
Explanation of Names
Formica obscuripes Forel, 1886

obscuripes - blackish (dark) legs
thatching - characteristic domed nest of fine twigs, petioles, rachises, or conifer needles
Note relatively abundant erect bristle on all surfaces of hind tibiae.
workers 4-7.5 mm
queens 10-11 mm
males 9-11 mm
- workers weakly polymorphic, with narrow headed, uniformly dark colored minors and major workers with a broad, and contrastingly bright red head
- bristles on all surfaces of hind tibiae (but few or none on scapes (cf. F. oreas)
- cross section of clypeus gently curved or curved with broadly obtuse medial angle (cf. trapezoidal cross section of F. obscuriventris clypeus)
See "Habitat"
Habitat changes from east to west -- Sandy prairie and oak savanna (Michigan to Minnesota, also Iowa and way-northern Missouri), dry-mesic tallgrass prairie (Nebraska, Dakotas, Canadian prairie provinces), mid-grass prairie, usually +/- riparian grassland (western Dakotas to New Mexico), sagebrush/rabbitbrush steppe (Alberta to New Mexico and Great Basin), conifer woodland and forest (northern, incl. Canadian Rockies to Washington and British Columbia).
Thes are predators of a variety of other arthropods and avid collectors of honeydew and extrafloral nectar. May attack and prey on other ants, particularly other Formica.
This is perhaps the best-known member of the Formica rufa group in North America, and thus the only one with a common name
Print References
Wheeler, G. C.; Wheeler, J. 1963. The ants of North Dakota. Grand Forks, North Dakota: University of North Dakota Press, viii + 326 pp.