Plagiolepis pygmaea

A widespread south-European species, with some related forms occurring in the Mediterranean region (Rigato & Toni, 2011).

Distribution based on Regional Taxon Lists
Palaearctic Region: Afghanistan, Andorra, Armenia, Austria, Balearic Islands, Belgium, Bulgaria, Canary Islands, China, Croatia, Czech Republic, France, Georgia, Germany, Gibraltar, Greece, Hungary, Iberian Peninsula, Iran, Israel, Italy, Malta, Montenegro, Morocco, Portugal, Republic of Macedonia, Romania, Slovakia, Slovenia, Spain, Switzerland, Turkey.

Other Ants
This species is a host for the inquiline and the workerless inquiline.

Other Insects
This ant has been associated with the butterflies, , and a species that has recently been recognized as two species: Polyommatus icarus and Polyommatus celin (Obregon et al. 2015).

Plants
Guiliani et al. (2019) observed this species foraging on extrafloral nectaries of the invasive Reynoutria x bohemica (Polygonaceae) in Tuscany. The habitats examined were river banks and disturbed habitats.

Nomenclature

 *  pygmaea. Formica pygmaea Latreille, 1798: 45 (w.q.) FRANCE. Schenck, 1852: 69 (m.); Wheeler, G.C. & Wheeler, J. 1953c: 135 (l.). Combination in Plagiolepis: Mayr, 1861: 43. Senior synonym of dufourii: Menozzi, 1925a: 19 (footnote); of obscuriscapus: Boer, 2008: 486. Current subspecies: nominal plus bulawayensis, mima, minu. See also: Stitz, 1939: 231; Kutter, 1977c: 185; Sharaf, Aldawood & Taylor, 2011: 207.
 * dufourii. Micromyrma dufourii Perris, 1878: 382 (w.) FRANCE. Junior synonym of Tapinoma erraticum: Dalla Torre, 1893: 165; Emery, 1913a: 40; Forel, 1915d: 43; of Plagiolepis pygmaea: Menozzi, 1925a: 19 (footnote).
 * obscuriscapus. Plagiolepis pygmaea var. obscuriscapus Santschi, 1923a: 137 (w.) ITALY. Stärcke, 1936: 278 (q.). Raised to species: Agosti & Collingwood, 1987a: 57. Junior synonym of pygmaea: Boer, 2008: 486.

Type Material
Sharaf et al. (2011) - France, Brive [not examined].

Worker
Sharaf et al. (2011) - TL 1.49-1.92, HL 0.38-0.46, HW 0.35-0.42, SL 0.32-0.46, EL 0.08-0.12, SI 91-110, CI 97-91, PRW 0.24-0.28, ML 0.41-0.44 (N=3).

Body uniformly brown or blackish brown, legs yellow, mandibles, antennae and coxae yellowish brown. Smooth and shining. Head distinctly longer than broad with convex sides. Occiput distinctly concave with rounded corners. Eyes relatively large with 9-10 ommatidia in the longest row (EL 0.12) and (0.28 x HW). Clypeus with several relatively long hairs, that are not restricted to the anterior margin. Scape surpassing posterior margin of head by at least one and half times its thickness. Funicular segments 2-4 distinctly broader than long. Fifth funicular segment longer than broad. Pubescence whitish, appressed and abundant on antennae, head and gaster but less abundant on mesosoma and legs. Posterior margins of all gastral tergites with many relative long and stiff hairs.