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Species Tetramorium immigrans - (Immigrant) Pavement Ant

Small Dark Brown Ants - Tetramorium immigrans - female French Fry Ants - Tetramorium immigrans - female Pavement Ant - Colony in sidewalk - Tetramorium immigrans Pavement Ant - Tetramorium immigrans Queen Size Comparison - Pavement Ants - Tetramorium immigrans Ants - Tetramorium immigrans Tetramorium sp.  - Tetramorium immigrans - female orange band ant - Tetramorium immigrans
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 Myrmicinae
Tribe Crematogastrini
Genus Tetramorium (Pavement Ants)
Species immigrans ((Immigrant) Pavement Ant)
Synonyms and other taxonomic changes
Regarding North American ants formerly thought to be Tetramorium caespitum (Linnaeus, 1758), Dr. James C. Trager says: "Almost all are now species E, with the exception of a population of T. tsushimae introduced in and slowly moving outward from St. Louis. There are a few places in Missouri and nearby Illinois where the two meet up, and apparently the polygyne, unicolonial T. tsushimae eventually wins out against mono- or oligogyne, multicolonial sp. E."
Explanation of Names
From Wagner, et al. (See below):
The [rather appropriate] name Tetramorium immigrans is applied to this population as follows:
Tetramorium caespitum var. immigrans SANTSCHI, 1927: 54;
junior synonym of T. caespitum: BOLTON 1979: 171;
revived from synonymy, raised to species rank, and lectotype designation hereby."
Workers ca. 3mm
Native across southern and central Europe, found in cities and towns throughout the United States and southern Canada (but mostly absent in the southern tier US states)
Urban parks, yards, vacant lots, under sidewalks and building rubble, especially, but also rural roadsides, farms, feedlots and auction yards, and rock quarries.
Omnivorous, fond of greasy human food scraps,
Introduced from Europe.
It is parasitized by another imported Myrmicine Anergates atratulus (also introduced).
Print References
Schlick-Steiner, Birgit C., Florian M. Steiner, Karl Moder, Bernhard Seifert, Matthias Sanetra, Eric Dyreson, Christian Stauffer, and Erhard Christian. 2006. A multidisciplinary approach reveals cryptic diversity in Western Palearctic Tetramorium ants (Hymenoptera: Formicidae). Molecular Phylogenetics and Evolution 40:259–273. (PDF)

Steiner, Florian M., Birgit C. Schlick-Steiner, James C. Trager, Karl Moder, Matthias Sanetra, Erhard Christian, and Christian Stauffer. 2006. Tetramorium tsushimae, a New Invasive Ant in North America. Biological Invasions 8(2):117-123. (PDF)

Herbert C. WAGNER, Wolfgang ARTHOFER, Bernhard SEIFERT, Christoph MUSTER, Florian M. STEINER & Birgit C. SCHLICK-STEINER just published "Light at the end of the tunnel: Integrative taxonomy delimits cryptic species in the Tetramorium caespitum complex (Hymenoptera: Formicidae)". Myrmecological News 25: 95-129 Vienna, October 2017
Internet References