Polyergus rufescens

Collingwood, C. A., 1979, The Formicidae (Hymenoptera) of Fennoscandia and Denmark., Fauna Entomologica Scandinavica 8, pp. 1-174 : 155-156

64. Polyergus rufescens (Latreille, 1798) Figs. 267,268.

Formica rufescens Latreille , 1798:44.

Worker. Reddish brown to brownish; head elongate; clypeus foreshortened with fla[[...]] anterior border, armed with long edentate sickle shaped mandibles. Maxillary palp short and very slender. Scale nodal; propodeum sharply raised in profile. Gula clypeus, occiput, dorsum of alitrunk with erect hairs, more profuse on gaster. Length 5.0-7.0 mm.

Ergatoid queen. As worker but with more massive alitrunk and hairs more sparse on alitrunk and gaster. Length: 7.0-9.0 mm.

Normal queen. Winged or with normal sclerites and normal queen shaped bread alitrunk. Colour as worker but appearance more shining with body hairs more sparse. Length: 8.0-9.5 mm.

Male. Black with eyes, legs and funiculi pale. Mandibles edentate, very thin and reduced. Palps very reduced. Head short and broad relative to alitrunk; eyes very large, hairless. Scale nodal but thinner in profile than in female castes, emarginate in front view. Scale and gaster with abundant long hairs. Length: 6.0-7.0 mm.

Distribution. South and Central Sweden, very local, recorded from Sk., Bl., Hall., Sm., 01., Upl. - Not found in British Isles. - Range: Spain to South Russia, Central Italy to Stockholm; rarcin Belgium and Netherlands.

Biology. This is the famous Amazon ant. Raiding forays are carried out by small troops of workers on hot days after mid summer and are invariably successful. The adversary ants are decapitated or have their heads pierced by the Polyergus with their pincerlike jaws. The worker pupae of members of the Formica fusca group, usually F. fusca or F. rufibarbis , are carried back to the parent nest for rearing as auxiliary workers by ants of the same or similar species introduced by earlier raids. Single queens whether ergatoid or normal secure adoption in nests of the auxiliary species by destroying and replacing the host queen. A mature colony may consist of a few dozen to a few hundred Polyergus workers and many more up to a few thousand of the auxiliary species. Queens and workers are unable to feed themselves or to rear brood. Nests are under flat stones in warm sheltered places.