Formica forsslundi Lohmander

52. Formica forsslundi Lohmander, 1949 Figs. 204. 205, 210.

Formica forsslundi Lohmander, 1949:163.

Worker. Bicoloured, appearance shining, pubescence very sparse. Eyes bare. Erect hairs are present sparsely on clypeus, head, alitrunk and on gaster tergites 2 to apex. Maxillary palps very short - 5 segmented. Head and scale deeply excised. Length: 4.0-6.5 mm.

Queen: Brownish, brilliantly shining. Head and scale deeply excised. Rest as worker. Size very small relative to worker. Length: 5.0-6.0 mm.

Male. Black. Mesonotum and gaster tergites with long hairs. Eyes bare. Head and mesonotum finely sculptured, scale and gaster distinctly shining. Maxillary palps very short. Head and scale broadly emarginate. Length: 5.5-6.5 mm.

Distribution. Locally abundant on wet heathland and in forest mires. Denmark: EJ and WJ. - Sweden: Sm. to Hrj. - Norway: HE only. - Finland: Ab, St, Tb and Ob (north to Rovaniemi). - Range: Switzerland (very local), Denmark to Urals, very local outside Fennoscandia.

Biology. This interesting species is found exclusively in wet heathland and mires in open forest. Colonies are started by queens securing adoption with Formica transkaucasica. Nests are constructed of leaf litter usually on the margins of wet ditches or fringes of boggy lakes. Alatae have been found in the nests during July.