Tetramorium species can be found worldwide with the largest diversity in Africa. Human commerce and movement have helped so of these species move around the world and establish non-native populations. In their non-native ranges, Tetramorium species can often be found in urban environments and can be the most common species present. Tetramorium species are often found living in buildings as well.
Tetramorium species can be identified by the two segmented waist; broad frons; 11 or 12-segmented antennae; three-segmented antennal club; antennal scrobe present dorsal to the eyes; eyes located along the midline of the head; lateral part of the clypeus forming a sharp wall anterior to the antennal insertion.
Tetramorium lanuginosum, also known as the wooly ant, can be found across the tropical and subtropical regions of the world. This is a monomorphic species that have workers covered with a coat of plumose, erect setae. Not yet considered to be a significant pest on the mainland, T. lanuginosum’s impact on small islands could be significant.
Tetramorium lanuginosum Mayr, 1870: 976 (w.) INDONESIA (Java). Indomalaya. "Indonesia, Java, Batavia." Naturhistorisches Museum, Wien, Austria (NHMW). CASENT0235202. Viehmeyer, 1916: 140 (q.); Imai, Baroni Urbani, et al. 1984: 8 (k.). Combination in Triglyphothrix: Emery, 1891: 4 (footnote); in Tetramorium: Bolton, 1985: 247. Senior synonym of Tetramorium australis, Tetramorium ceramensis, Tetramorium felix, Tetramorium flavescens, Tetramorium laevidens, Tetramorium mauricei, Tetramorium orissana, Tetramorium striatidens, Tetramorium tricolor:Bolton, 1976: 350. See also: Hita Garcia & Fisher, 2011: 27.
Worker: HL 0.66-0.69mm, HW 0.59-0.63mm, SL 0.42-0.46mm, EL 0.14-0.15mm, MeSL 0.68-0.70 (n=5) (MEM specimens). Overall color is orange with a darker colored gaster, but not distinctly bicolored. Head covered with short, erect, hair-like setae; eyes smaller and located laterally at about the midline of the head; mandibles triangular in shape; posterior edge of clypeus forming an abrupt wall anterior to the antennal insertion point giving the impression of a large, deep antennal socket; 12-segmented antennae with a three-segmented club; apical segment of antennal club over half the length of the club; frontal process widened over the antennal insertion point giving the dorsal edge of the antennal scrobe a notched appearance; antennal scrobe present dorsal to the eye; rugoreticulate sculpturing. Mesosoma covered with dense, erect, hair-like setae; dorsal surface evenly curved; propodeal spines bidentate with the dorsal spine slightly less the twice the size of the ventral spine; reticulate sculpturing; Legs with dense, hair-like setae. Waist two-segmented; dorsal surface with dense, erect, hair-like setae; both petiolar node and postpetiolar node subcircular when viewed dorsally with reticulate sculpturing. Gaster with the same setation as the rest of the body; first tergite enlarged to take up more than half then length; first tergite can be darkened in color.
Queen: no specimens (based on antwiki.org pictures) Color ranges from orangish brown to brown with a slightly darker colored gaster. Head with dense, hair-like setae; eyes located laterally at about the midline of the head; three ocelli present; mandibles triangular in shape; posterior border of the clypeus forming a sharp wall anterior to the antennal insertion point; antennae 12-segmented with a three-segmented club; frontal processes expanded over antennal insertion point giving the dorsal edge of the antennal scrobe a notched look; scrobe located dorsal to the eyes; overall sculpturing rugoreticulate. Mesosoma with dense, erect, hair-like setae; enlarged with four wings or wing scars; propodeal spines well developed; overall sculpturing reticulate. Waist is two-segmented; dense, erect, hair-like setae covers the dorsal surface; both nodes subcircular in shape; dorsal surface of nodes reticulate. Gaster smooth and shining with erect, hair-like setae; first tergite enlarged to take up more than half the length of the gaster.
Male: no specimens
Tetramorium lanuginosum can be separated from other similar species on the area by the dense covering of hair-like setae present across the entire ant and its reticulate sculpturing.
Biology and Economic Importance
Tetramorium lanuginosum can be found in tropical and subtropical regions worldwide. It has an almost continuous range going from India all the way to northern Australia where it can be found in rural and urban environments, which indicates that this could be its native range (Wetterer, 2010). Outside of Southeast Asia, T. lanuginosum is commonly found in the South Pacific Islands and around Madagascar. Tetramorium lanuginosum has been introduced to the Southeastern Gulf States, though it has not been reported to be extremely prevalent. This suggests that the endemic ant species on the area and other nonnative ants could be outcompeting it.
Tetramorium lanuginosum currently does not pose a large economical threat in the southeastern United States or a lot of the mainland areas where it can be found. It could potentially become a significant pest on islands where there is less competition with other ants though (Wetterer, 2010).
Native Range: Tropical to subtropical Southeast Asia (Wetterer, 2010).
Afrotropical Region: Yemen (antweb.org).
Australasian Region: Australia (type locality), New Guinea (antweb.org and antwki.org).
Indo-Australian Region: American Samoa, Fiji, French Polynesia, Guam, Hawaii, Indonesia (type locality), Kiribati, Malaysia, Marshall Islands, Micronesia (Federated States of), New Guinea, Samoa, Singapore, Solomon Islands, Tokelau, Tonga, Wallis and Futuna Islands (antweb.org and antwki.org).
Malagasy Region: Comoros, Madagascar, Mauritius, Mayotte, Réunion, Seychelles (antweb.org and antwki.org).
Nearctic Region: United States (antwki.org).
Neotropical Region: Aruba, Barbados, Costa Rica, Dominican Republic, Ecuador, Galapagos Islands, Greater Antilles, Mexico, Netherlands Antilles, Nicaragua, Puerto Rico (antweb.org and antwki.org).
Oriental Region: Bangladesh, Bhutan, Borneo, India, Krakatau Islands, Myanmar, Nicobar Island, Philippines, Sri Lanka, Thailand, Vietnam (antweb.org and antwki.org).
Palearctic Region: China, Iberian Peninsula, Iraq, Israel, Japan, Malta, Saudi Arabia, Spain, United Arab Emirates (anrweb.org and antwki.org).
U.S. Distribution: AL, FL, GA, HI, LA, MS, SC (antweb.org and MEM)
Southeastern U.S. Distribution: AL, FL, GA, LA, MS, SC (antweb.org and MEM)
Funding for the ant work being done by the MEM in Alabama and Mississippi is from several sources including the National Institute of Food and Agriculture, United States Department of Agriculture, under Project No. MIS-012040, the Mississippi Agricultural and Forestry Experiment Station at Mississippi State University, with support from State Project MIS-311080, NSF Grants BSR-9024810 and DFB-9200856, the Tombigbee National Forest (U.S. Forest Service), the Noxubee Wildlife Refuge, Mississippi Natural Heritage Program Research Grant, USDA Forest Service Agreement No. 08-99-07-CCS-010, the William H. Cross Expedition Fund, and primarily by the USDA-ARS Areawide Management of Imported Fire Ant Project. Additionally, special cooperation has been provided by State Parks, National Forests, National Wildlife Refuges, the Natchez Trace Parkway, and from various private landowners in both Alabama and Mississippi.
Bolton, B. 1976. The ant tribe Tetramoriini (Hymenoptera: Formicidae). Constituent genera, review of smaller genera and revision of Triglyphothrix Forel. Bulletin of the British Museum (Natural History). Entomology 34:281-379.
Bolton, B. 1985. The ant genus Triglyphothrix Forel a synonym of Tetramorium Mayr. (Hymenoptera: Formicidae). Journal of Natural History 19:243-248.
Emery, C. 1891. Exploration scientifique de la Tunisie. Zoologie. - Hyménoptères. Révision critique des fourmis de la Tunisie. Paris: Imprimerie Nationale, iii + 21 pp.
Hita Garcia, F.; Fisher, B. L. 2011. The ant genus Tetramorium Mayr (Hymenoptera: Formicidae) in the Malagasy region—introduction, definition of species groups, and revision of the T. bicarinatum, T. obesum, T. sericeiventre and T. tosii species groups. Zootaxa 3039:1-72.
Imai H. T., Baroni Urbani C., Kubota M., Sharma G. P., Narasimhanna M. N., Das B. C., Sharma A. K., Sharma A., Deodikar G. B., Vaidya V. G. & Rajasekarasetty M. R. 1984. Karyiological survey of Indian ants. Jpn. J. Genet. 59: 1-32.
Mayr, G. 1870. Neue Formiciden. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wien 20:939-996.
Viehmeyer, H. 1916 ("1915"). Ameisen von Singapore. Beobachtet und gesammelt von H. Overbeck. Archiv für Naturgeschichte (A)81(8):108-168.
Wetterer, J.K. 2010. Worldwide spread of the wooly ant, Tetramorium lanuginosum (Hymenoptera: Formicidae). Myrmecological News 13: 81-88.