Myrmica excelsa

Radchenko and Elmes (2010) - M. excelsa is a rather thermophilous species. In the Russian Far East it inhabits fir and mixed forests of the southern type, that support a considerable number of rare and relict taxa. In Korea, where the climate is definitely warmer and drier than in the Far East of Russia, M. excelsa was found at a low and middle altitudes (100-650 m), preferring deciduous and mixed forests (oak, beech, sweet chestnut, pine) and shrubby areas but usually avoiding open grasslands. In these forests workers appeared to forage close to the soil surface under litter and dead leaves and were very cryptic, even for lobicornis-group species (personal observations). In Japan M. excelsa is rather a rare species living in grasslands at altitudes between 500 and 1500 m. In Japan and Korea nests are usually built in the soil, often under stones, but in the Russian Far East nests are mostly in dead wood. Nuptial flight in August-September (see also Kupyanskaya 1990; Imai et al. 2003; Radchenko 2005).

Identification
A member of the excelsa complex of the lobicornis species group. Radchenko and Elmes (2010) - M. excelsa is a distinctive species belonging to the lobicornis-group. Its most characteristic feature is the raised lateral portions of clypeus that form a sharp ridge in front of the antennal insertions, so that antennal sockets are distinctly separated from the clypeal surface (as in species of Tetramorium). This led Kim et al. (1997) to describe the antennal pits as "jar-like". Only two more Myrmica species are known to possess this feature: Myrmica transsibirica and Myrmica tamarae, both are lobicornis-group species. M. excelsa well differs from both by the shape of its antennal scape (for details see Kupyanskaya 1990; Radchenko 2005, and Key, Chapter 5.3), but due to the Tetramorium-like clypeus we place them together in the excelsa-complex.

Distribution
Southern part of Russian Far East, NE China, Korean Peninsula, Japan.

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

Nomenclature

 *  excelsa. Myrmica excelsa Kupyanskaya, 1990: 115, figs. 16, 19, 20 (w.q.m.) RUSSIA. Senior synonym of cadusa: Radchenko, 2005b: 140; of sinica: Radchenko, Zhou, et al. 2008: 783. See also: Yamane, 2008: 29; Radchenko & Elmes, 2010: 131.
 * sinica. Myrmica sinica Wu & Wang, 1995: 94, figs. 137, 145, 146 (w.q.) CHINA. Junior synonym of excelsa: Radchenko, Zhou, et al. 2008: 783.
 * cadusa. Myrmica cadusa Kim, Park & Kim, 1997: 425, fig. 1 (w.) SOUTH KOREA. Junior synonym of excelsa: Radchenko, 2005b: 140.

Etymology
Radchenko and Elmes (2010) - from the Latin word excelsa = elevated or tall, to describe the elevated part of the clypeus in front of the antennal insertions.