Formica uralensis Ruzsky

55. Formica uralensis Ruzsky, 1895 Figs. 219,220.

Formica uralensis Ruzsky, 1895: 13; 1896:69 (German translation).

Worker. Head entirely black, dark area on dorsum of promesonotum dense black, gaster black, rest of alitrunk and appendages yellowish to brownish red. Head as broad as long, antennal scape broad and short. Frontal triangle sculptured and dull. Bristlelike hairs on dorsum of head, gula, alitrunk and gaster usually present but variable in number. Length: 4.5-8.0 mm.

Queen. As worker but with whole of mesoscutum dark. Legs pitchy. Frontal triangle sculptured and dull; eyes bare. Length: 9.0-11.0 mm.

Male. Head, mandibles, antennal scapes, alitrunk and gaster dense black. Mandibles denticulate with up to 5 teeth but variable. Clypeus, head, promesonotum and scale with widely spaced hairs; eyes bare. Wings dusky, frontal triangle dull. Length: 9.0-11.0 mm.

Distribution. Local in Denmark: SJ, EJ, WJ, NEJ, and Norway: HE and F0 (Fjellberg, 1975). - Widely distributed in Sweden and Finland. - Range: Northeast Europe including N. Germany, Baltic States and West USSR; one record from Swiss Alps. Widely distributed in Mongolia and Central Siberia.

Biology. In Europe F. uralensis is typically found on lowland open mosses with scattered trees, more occasionally on drier heath. Nests may be isolated or in groups and are built up of leaf litter and twigs into rounded dome. The nest surface is of fine material which covers a large brood incubation chamber resting on a surface of coarse long twigs. Rosengren (1969) has studied its habits in South Finland; unlike members of the F. rufa group, this species does not go deep within the nest to hibernate but the ants clump together under peat moss or among tree roots away from the summer nest. Food is mainly honey dew from surrounding betula scrub or pines. Although this species has superficial similarities to F. rufa group species it is morphologically well differentiated with its broad black head, short thick antennae and wide coarsely sculptured frontal triangle.

Nests are usually polygynous and may reproduce by colony fission but fresh colonies may also originate from adoption of fertile queens by F. transkaucasica. Alatae occur in July. Its marshy habitat in Europe contrasts with the dry steppe habitat in Asia and may be related to the inability of this species to survive aggressive competition from other wood ant species since according to Rosengren (1969), although F. uralensis defends its terrirory it is easily overwhelmed by other ants such as F. sanguinea and Myrmica rubra.