Tetramorium caldarium

An increasingly common tramp species. Little is known about its biology and the effect of Tetramorium caldarium on other ants is not known.

Identification
A member of the Tetramorium simillimum species group.

Tetramorium caldarium is a small reddish ant. This species has a monomorphic worker caste with 12-segmented antennae, three-segmented antennal club, antennal scrobes, short antennal scapes that do not surpass the posterior margin of the head, a gradually sloped mesosoma, and small propodeal spines. Like all myrmicines, T. caldarium has two waist segments and a gaster armed with a stinger. (Antkey)

Distribution
Tetramorium caldarium is believed to be native to Africa and is now widely distributed across the Pacific and other tropical regions. (Antkey)

Distribution based on Regional Taxon Lists
Afrotropical Region: Ivory Coast, Kenya, Saint Helena, Tanzania. Australasian Region: Norfolk Island. Malagasy Region: Madagascar, Mauritius. Nearctic Region: United States. Neotropical Region: Barbados, Bermuda, Brazil, Colombia, Dominican Republic, Ecuador, Galapagos Islands, Greater Antilles, Haiti, Mexico, Peru, Puerto Rico. Oriental Region: India. Palaearctic Region: Balearic Islands, Canary Islands, Egypt, Germany, Iberian Peninsula, Monaco, Poland, Spain, United Kingdom of Great Britain and Northern Ireland.

Nomenclature

 *  caldarium. Tetrogmus caldarius Roger, 1857: 12 (w.q.) POLAND. Meinert, 1861: 331 (m.). Combination in Tetramorium: Bolton, 1979: 169. Junior synonym of simillimum: Roger, 1862c: 297. Revived from synonymy: Bolton, 1979: 169. Senior synonym of hemisi, minutum: Bolton, 1979: 169; of transformans: Bolton, 1980: 310. See also: Czechowski, Radchenko & Czechowska, 2002: 68; Bharti & Kumar, 2012b: 21.
 * transformans. Tetramorium pauper st. transformans Santschi, 1914b: 104 (w.) KENYA. Junior synonym of caldarium: Bolton, 1980: 310.
 * hemisi. Tetramorium pusillum var. hemisi Wheeler, W.M. 1922a: 193 (w.) DEMOCRATIC REPUBLIC OF CONGO. Junior synonym of caldarium: Bolton, 1979: 169.
 * minutum. Tetramorium minutum Donisthorpe, 1942a: 30 (q.) EGYPT. Junior synonym of caldarium: Bolton, 1979: 169.

Additional References

 * Bharti, H. & Kumar, R. 2012b. Taxonomic studies on genus Tetramorium Mayr, with report of two new species and three new records including a tramp species from India with a revised key. ZooKeys 207: 11-35.