Formica polyctena Forster

59. Formica polyctena Forster, 1850 Figs. 172,236-241.

Formica polyctena Forster, 1850: 15.

Worker. 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.

Queen. As F. rufa but middle of scutellum less shining, with fine longitudinal striae and punctures. Frons distinctly shining but rest of body due to coarser sculpture presenting a somewhat more matt appearance than in F. rufa. Length: 9.0-10.5 mm.

Male. Eye hairs very sparse and short. Erect hairs on promesonotum sparse, very short or absent on metanotum. Punctures on gaster and frons shallow and widely spaced. Length: 9.0-10.5 mm.

Distribution. Local, Denmark: EJ, NEJ, NEZ. - Sweden: Sk., Bl., Hall., Gtl., Nrk., Sdm., Upl., Vrm. - Norway: 0, AK, VE. - Finland: N, Ka, Ta. - Not found in England. - Range: Spain to Siberia, Italian Alps to latitude 60° in Sweden.

Biology. This is accepted as a good species by most European authors, eg. Betrem (1960), Dlussky (1967), Kutter (1977). Some samples of F. 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.