Formica polyctena

Identification
Erect hairs on head and alitrunk very sparse and short or absent, except on posterior margins of mesopleura. Gula hairs, if present, are restricted to one or two very weak hairs. Microsculpture is usually slightly coarser than in F. rufa but punctures and micropunctures are widely spaced as in that species. Length: 4.0-8.5 mm (Collingwood 1979).

Distribution
Spain to Siberia, Italian Alps to latitude 60º in Sweden (Collingwood 1979).

This taxon was described from Germany.

Biology
Collingwood (1979) - This is accepted as a good species by most European authors, eg. Betrem (1960), Dlussky (1967), Kutter (1977). Some samples of Formica rufa tend to approach the hairless condition of F. polyctena however, making certain determination sometimes difficult. Elton (priv. communication) found that F. polyctena in its most typical form readily accepted fertile queens and pupae from other distant nests of the same species but were always antagonistic to and rejected such from both polygonous and monogynous colonies of F. rufa. This is usually found in a group of nests and always has many queens, sometimes up to 1,000 or more.

This is a relatively well studied species and one that had long confounded myrmecologists in regards to its specific taxonomic identity. Collingwood's statements above are indicative of these problems. What follows is a more recent summary that provides insight into our latest understanding of this ant. This is taken from Siefert et al (2011). The details for the cited works are given in the original publication.

The wood ant species Formica polyctena and Formica rufa are important elements of temperate forest ecosystems of the West Palaearctic. They are considered to give protection against a number of pest insects in natural and secondary, managed forests (reviewed by Otto 1967) and are a symbol and main target of nature conservation in many countries of Europe. Yarrow (1955) and Betrem (1960) considered F. polyctena and F. rufa as clearly different species and this view had been generally adopted for 35 years. The situation changed when Seifert (1991) published a comprehensive study on external morphology and biological parameters of 430 nests collected in different regions of Central, East and North Europe. In addition to the typical F. polyctena and F. rufa, he found a third entity which was intermediate in each investigated phenotypic or biological character: body size, eight size-corrected pilosity characters, monogyny frequency, size of nest populations, diameter of nest mounds and infestation rate with epizootic fungi. He concluded that the third entity was a fertile hybrid between F. polyctena and F. rufa.

Nesting Biology
Formica polyctena often forms huge supercolonies with several hundred nests. Single nests may be vary large, particularly in coniferous forests.

Nomenclature

 * major. Formica major Nylander, 1849: 29 (w.) FINLAND. Junior synonym of rufa: Emery & Forel, 1879: 450. Revived from synonymy: Betrem, 1926: 213. Senior synonym of piniphila: Betrem, 1953: 325. Junior synonym of rufa: Yarrow, 1955a: 3; Betrem, 1960b: 76; Kutter, 1977c: 273; of polyctena: Radchenko, 2007: 37 (major is best regarded as a nomen oblitum, therefore polyctena takes priority).
 *  polyctena. Formica polyctena Foerster, 1850a: 15 (w.q.m.) GERMANY. Junior synonym of rufa: Nylander, 1856b: 60; Emery & Forel, 1879: 450; Dalla Torre, 1893: 208; Yarrow, 1955a: 3. Subspecies of rufa: Forel, 1915d: 58; Emery, 1925b: 253; Stitz, 1939: 339; Boven, 1947: 189. Status as species: Bondroit, 1917a: 174; Müller, 1923: 144; Betrem, 1926: 212; Betrem, 1960b: 64; Dlussky, 1967a: 93; Dlussky & Pisarski, 1971: 187; Kutter, 1977c: 272; Collingwood, 1979: 144. Senior synonym of minor: Betrem, 1960b: 64; Dlussky, 1967a: 93; of nuda: Dlussky, 1967a: 93; Dlussky & Pisarski, 1971: 187; of major: Radchenko, 2007: 37 (major is best regarded as a nomen oblitum, therefore polyctena takes priority). See also: Mabelis, 1979: 451; Gösswald, 1989: 18; Atanassov & Dlussky, 1992: 279; Czechowski & Douwes, 1996: 125.
 * nuda. Formica (Formica) rufa var. nuda Karavaiev, 1930b: 148 (w.) SWEDEN. [Unresolved junior primary homonym of nuda Ruzsky, above.] Junior synonym of rufa: Karavaiev, 1936: 240; Yarrow, 1955a: 4; of polyctena: Dlussky, 1967a: 93; Dlussky & Pisarski, 1971: 187.
 * minor. Formica minor Gösswald, 1951: 436 (w.q.) GERMANY. [First available use of Formica rufa subsp. pratensis var. minor Gösswald, 1941: 78; unavailable name.] Junior synonym of polyctena: Betrem, 1960b: 64; Dlussky, 1967a: 93.

Additional References

 * Seifert, B., J. Kulmuni, and P. Pamilo. 2010. Independent hybrid populations of Formica polyctena X rufa wood ants (Hymenoptera: Formicidae) abound under conditions of forest fragmentation. Evol. Ecol. 24:1219-1237.