Plagiolepis alluaudi

Plagiolepis alluaudi is a tiny Old World ant that has spread to many parts of the world through human commerce. It is a primarily tropical species, apparently native to Madagascar and neighboring islands. It has become a pest on Pacific islands and in European greenhouses (Wetterer, 2013).

Distribution based on Regional Taxon Lists
Afrotropical Region: Comoros, Kenya, Saint Helena. Australasian Region: New Caledonia, Norfolk Island. Indo-Australian Region: Borneo, Cook Islands, Fiji, French Polynesia, Hawaii, New Guinea, Niue, Solomon Islands, Tonga, Vanuatu. Malagasy Region: Madagascar, Mayotte, Réunion, Seychelles. Nearctic Region: United States. Neotropical Region: Barbados, Bermuda. Palaearctic Region: China, Japan, Switzerland.

There is a single record of this species from Catalina Island, California (collected by William M. Mann; SMITH 1957). Many researchers have made extensive ant collections in California, but have never produced another record of P. alluaudi, suggesting that either the California population has been extirpated or the one record was based on a labeling error. In fact, this one record of P. alluaudi is very suspect: I have been unable to find any other records of ants collected by William M. Mann on Catalina Island (Wetterer 2013).

Nomenclature

 *  alluaudi. Plagiolepis alluaudi Emery, 1894a: 71 (w.) SEYCHELLES IS. Forel, 1907a: 30 (q.). Senior synonym of augusti, foreli, mactavishi, ornata: Smith, M.R. 1958b: 196. See also: Smith, D.R. 1979: 1423.
 * mactavishi. Plagiolepis mactavishi Wheeler, W.M. 1908c: 166 (w.) FRENCH POLYNESIA (Society Is). Wheeler, W.M. 1922f: 318 (q.); Santschi, 1928b: 37 (m.). Junior synonym of alluaudi: Smith, M.R. 1958b: 196.
 * foreli. Plagiolepis foreli Santschi, 1920g: 165, fig. 1 (w.) SWITZERLAND. Subspecies of alluaudi: Emery, 1921d: 318. Junior synonym of alluaudi: Smith, M.R. 1958b: 196.
 * ornata. Plagiolepis foreli var. ornata Santschi, 1920g: 166 (w.) NEW CALEDONIA. Subspecies of alluaudi: Emery, 1921d: 318. Junior synonym of alluaudi: Smith, M.R. 1958b: 196.
 * augusti. Plagiolepis augusti Emery, 1921d: 317. Replacement name for foreli Mann, 1921: 473. [Junior primary homonym of foreli Santschi, 1920g: 165.] Junior synonym of alluaudi: Smith, M.R. 1958b: 196.
 * foreli. Plagiolepis foreli Mann, 1921: 473 (w.) FIJI IS. [Junior primary homonym of foreli Santschi, above.] Replacement name: augusti Emery, 1921d: 317.