Formica exsecta

Identification
Bicoloured with gaster dark brown, rest of body reddish with varying amount of dark colour on head and promesonotum. Head strongly excised posteriorly; maxillary palps 6 segmented, long as half head length. Scale strongly emarginate. Eyes with very distinct erect hairs which are normally abundant. Body pilosity variable - erect hairs on all gaster tergites, on clypeus and on dorsum of head, sometimes also on occipital margins. Clypeus not impressed. Length: 4.5-7.5 mm (Collingwood 1979).

Distribution
Central Spain to Urals, Appenines to extreme north of Europe(Collingwood 1979).

This taxon was described from Finland. It is also found in Italy, United Kingdom of Great Britain and Northern Ireland.

Biology
This is an active aggressive species building mounds of leaf litter in open woodland, moorland and rough pasture. On disturbance the ants swarm out and bite vigorously. Nests may contain a thousand or more workers with more than one queen. They are often grouped with amicable interchange of workers between each. F. exsecta is mainly aphidicolous tending aphids on Juniperus, Picea and other trees but is also predaceous. Colonies extend by nest splitting but single queens also start colonies by securing acceptance in nests of Formica lemani or Formica fusca. Alatae occur in July (Collingwood 1979).

Nomenclature

 *  exsecta. Formica exsecta Nylander, 1846a: 909, pl. 18, fig. 20 (w.q.m.) FINLAND. Combination in F. (Coptoformica): Müller, 1923: 146. Senior synonym of dalcqi, etrusca: Bernard, 1967: 323; of exsectopressilabris: Bernard, 1967: 323; Dlussky & Pisarski, 1971: 194; of kontuniemii, sudetica, wheeleri Stitz: Dlussky, 1967a: 100; Dlussky & Pisarski, 1971: 194; of rubens: Dlussky, 1964: 1027; of nemoralis: Seifert, 2000a: 526. See also: Donisthorpe, 1915d: 273; Parapura, 1972: 763; Kutter, 1977c: 283; Agosti & Hauschteck-Jungen, 1988: 280; Kupyanskaya, 1990: 200; Atanassov & Dlussky, 1992: 282; Seifert, 2000a: 525; Radchenko, 2007: 36.
 * exsectopressilabris. Formica exsecta var. exsectopressilabris Forel, 1874: 52 (w.q.m.) SWITZERLAND. Subspecies of pressilabris: Dalla Torre, 1893: 205. Raised to species: Bondroit, 1912: 352; Bondroit, 1918: 63. Subspecies of exsecta: Karavaiev, 1927c: 284; Karavaiev, 1936: 255; Boven, 1947: 189. Junior synonym of exsecta: Bernard, 1967: 323; Dlussky & Pisarski, 1971: 194.
 * rubens. Formica exsecta var. rubens Forel, 1874: 51 (w.) SWITZERLAND. Raised to species: Bondroit, 1918: 62. Subspecies of exsecta: Ruzsky, 1925b: 43; Emery, 1925b: 257. Junior synonym of exsecta: Dlussky, 1964: 1027.
 * etrusca. Formica exsecta var. etrusca Emery, 1909b: 191, fig. 5 (w.) ITALY. Raised to species: Bondroit, 1918: 64. Subspecies of exsecta: Emery, 1925b: 257; Karavaiev, 1926e: 196. Junior synonym of exsecta: Bernard, 1967: 323.
 * dalcqi. Formica dalcqi Bondroit, 1918: 63 (w.) FRANCE. Subspecies of exsecta: Emery, 1925b: 257. Junior synonym of exsecta: Bernard, 1967: 323.
 * sudetica. Formica exsecta var. sudetica Scholz, 1924: 48 (w.) POLAND. Junior synonym of exsecta: Dlussky & Pisarski, 1971: 194.
 * kontuniemii. Formica kontuniemii Betrem, 1954: 230 (w.) FINLAND. Junior synonym of exsecta: Dlussky, 1967a: 100; Dlussky & Pisarski, 1971: 194.
 * nemoralis. Formica nemoralis Dlussky, 1964: 1037 (w.m.) UKRAINE. Junior synonym of forsslundi: Dlussky, 1967a: 105; of exsecta: Seifert, 2000a: 526.

Additional References

 * Collingwood, C. A. 1979. The Formicidae (Hymenoptera) of Fennoscandia and Denmark. Fauna Entomol. Scand. 8:1-174.