Myrmica kotokui

Radchenko and Elmes (2010) - M. kotokui is one of the commonest Myrmica species in East Asia, living in various habitats. It prefers different kinds of forests (pine, oak, maple, birch, lime, spruce, fir, larch), it occurs also in shrublands and meadows, but avoids dry places. In Japan on Honshu Island we found it living at altitudes of 1200-2000 m, further north on Hokkaido Island it lived at lower altitudes from sea level to about 1000 m. It builds nests predominantly in the soil, very often under stones, but also constructs soil mounds or nests in decayed wood. In Japan nests were usually found under “Bamboo grass” or in open deciduous forest. In contrast to the closely related Myrmica ruginodis, colonies of M. kotokui are quite polygynous, with population of the nests reaching several thousand workers (Kikuchi et al. 1999). Nuptial night occurs in August-September.

Identification
Radchenko and Elmes (2010) - A member of the rubra group that is very difficult to distinguish from Myrmica ruginodis. Female castes differ from M. ruginodis mainly by the shape and sculpture of the petiole: the petiolar node dorsum (seen in profile) is slightly more rounded without a distinct dorsal plate, and the sides of the petiolar node are smoothly sculptured whereas M. ruginodis has coarse longitudinal rugosity (in these respects it more resembles M. rubra). In males of M. kotokui the clypeus is distinctly longitudinally striated while in males of M. ruginodis it is smooth.

Key to Myrmica of species of East Siberia, Russian Far East, Mongolia, Korean Peninsula, northern China, and Japan

Distribution
Russian Far East, Korean Peninsula, NE China and Japan.

Distribution based on Regional Taxon Lists
Palaearctic Region: China, Democratic Peoples Republic of Korea, Japan, Republic of Korea, Russian Federation.

Nomenclature

 *  kotokui. Myrmica rubra subsp. kotokui Forel, 1911e: 267 (w.q.m.) JAPAN. Raised to species: Collingwood, 1976: 300. Senior synonym of orientalis: Radchenko, 2005b: 142. See also: Radchenko & Elmes, 2010: 170.
 * orientalis. Myrmica ruginodis subsp. orientalis Karavaiev, 1926f: 65, fig. 1 (w.) RUSSIA. Kuznetsov-Ugamsky, 1928b: 37 (q.m.). Subspecies of rubra: Weber, 1947: 450. Raised to species: Kupyanskaya, 1990: 101. Junior synonym of ruginodis: Radchenko, 1994f: 73; of kotokui: Radchenko, 2005b: 142.

Etymology
Radchenko and Elmes (2010) - Forel does not say to whom he dedicated this species. Most probably he had in mind Shusui Kotoku, a well known Japanese socialist, journalist and author, who was hanged six months earlier for treason, on 24th January 1911, and was considered by many to be a martyr for peace and freedom.