Lasius orientalis

This species is distributed in mountainous areas and is a temporary parasite of. Nuptial flights take place during July (Yamauchi et al., 1986; Japanese Ant Image Database).

Identification
Within the subgenus distinctive by its flattened antennal scape and the very thick, low petiolar scale (in profile), which is gradually widened to the apex when seen in front or from behind.

Distribution
Radchenko (2005) - Southern part of Russian Far East (Amursky and Primorsky Regions, Islands Shikotan and Kunashir), Korean Peninsula, Japan (Hokkaido, northern and central Honshu).

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

Nomenclature

 *  orientalis. Lasius fuliginosus var. orientalis Karavaiev, 1912b: 586 (w.) KOREA. Junior synonym of fuliginosus: Wilson, 1955a: 138; of nipponensis: Espadaler, Akino & Terayama, 2002: 340. Revived from synonymy, raised to species and senior synonym of ouchii, teranishii: Radchenko, 2005a: 87.
 * teranishii. Lasius (Chthonolasius) teranishii Wheeler, W.M. 1928d: 120 (q.) JAPAN. Yamauchi & Hayashida, 1968: 399 (w.m.). Combination in L. (Dendrolasius): Wilson, 1955a: 146. Senior synonym of ouchii: Wilson, 1955a: 146. Junior synonym of orientalis: Radchenko, 2005a: 87. See also: Yamauchi, 1979: 174; Kupyanskaya, 1989: 786.
 * ouchii. Lasius (Chthonolasius) ouchii Teranishi, 1940: 76 (q.) JAPAN. Junior synonym of teranishii: Morisita, 1945: 23; of orientalis: Radchenko: 2005: 87..

Worker
Radchenko (2005) - (neotype in brackets) workers from the nest of the neotype specimen (n = 16) [mean data are in square brackets]: HL1 = 1.06-1.26 (1.22) [1.17], HL2 = 1.12-1.33 (1.32) [1.25], HW1 = 1.04-1.23 (1.19) [1.15], HW2 = 0.70-0.80 (0.77) [0.75], SL = 1.01-1.12 (1.09) [1.06], OL = 0.18-0.27 (0.25) [0.23], AL = 1.18-1.44 (1.34) [1.32]; CI = 0.96-1.00 (0.98) [0.98], CLI = 1.05-1.09 (1.08) [1.07], CWI = 1.49-1.57 (1.55) [1.54], SI1 = 0.88-0.95 (0.90) [0.90], SI2 = 0.89-0.96 (0.92) [0.92], OI = 0.18-0.22 (0.21) [0.20].

Petiolar scale (seen in proflle) thick, low, not narrowing to the top; when seen in front or from behind, it gradually widens to the top; scape distinctly flattened, ratio of min/max diameters of the scape ≤ 0.5; head with convex sides, gradually and slightly narrowing anteriorly, with emarginate occipital margin; scape and legs with numerous short subdecumbent hairs; promesonotal dorsum and occipital margin with a few quite short standing hairs.

Queen
Radchenko (2005) - Petiolar scale (seen in profile) thick, low, not narrowing to the top; when seen in front or from behind it gradually widens to the top; scape and legs, including the first tarsal joint, remarkably flattened, ratio of min/max diameters of scape and hind tibiae ≤ 0.4; head with emarginate occipital margin, but not cordiform and at most slightly wider than long; legs and scape with very dense decumbent pubescence; head, alitrunk and gaster with very dense decumbent pubescence; alitrunk dorsum with sparse, short erect hairs.

Type Material
Radchenko (2005) -Neotype worker (designated here, see below), “Buhta Gaidamak, No. 3196, 2l.V.1900, leg. P. Shmidt”, “Lasius fuliginosus var. orientalis Karaw. Typus” (both labels hand written by Karawajew).

References based on Global Ant Biodiversity Informatics

 * Chapman, J. W., and Capco, S. R. 1951. Check list of the ants (Hymenoptera: Formicidae) of Asia. Monogr. Inst. Sci. Technol. Manila 1: 1-327
 * Choi B.M. 1985. Study on distribution of ants (Formicidae) from Korea (1). Formic fauna in Mt. Songni. Cheongju Sabom Taehak Nonmunjip (Journal of Cheongju National Teachers' College) 22:401-437.
 * Choi B.M. 1986. Studies on the distribution of ants (Formicidae) in Korea. Journal of Chongju National Teacher College 23: 317-386.
 * Choi B.M. 1998. Distribution of ants (Formicidae) in Korea (19) Ants fauna from Chungcheongbukdo Province. Cheongju Tea. Coll. 35: 213-266.
 * Choi B.M., Bang, J.R. 1992. Studies on the distribution of ants (Formicidae) in Korea (9). Ant fauna in Mt. Togyusan. Korean Journal of Applied Entomology 31:101-112.
 * Choi B.M., K. Ogata, and M. Terayama. 1993. Comparative studies of ant faunas of Korea and Japan. 1. Faunal comparison  among islands of Southern Korean and northern Kyushu, Japan. Bull. Biogeogr. Soc. Japan 48(1): 37-49.
 * Choi B.M., Kim, C.H., Bang, J.R. 1993. Studies on the distribution of ants (Formicidae) in Korea (13). A checklist of ants from each province (Do), with taxonomic notes. Cheongju Sabom Taehakkyo Nonmunjip (Journal of Cheongju National University of Education) 30: 331-380.
 * Collingwood C. A. 1976. Ants (Hymenoptera: Formicidae) from North Korea. Annales Historico-Naturales Musei Nationalis Hungarici 68:
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Hayashida K. 1972. Ecological survey on ants in Nakagawa Experiment Forest of Hokkaido University. Res. Bull. Exper. Forests, Coll. Agr., Hokkaido Univ. 29: 25-36.
 * Ichinose K. 1990. The Ant Fauna of the Tomakomai Experiment Forest, Hokkaido University (Hymenoptera: Formicidae) with Notes on the Nuptial Season. Research Bulletins of College Experiment Forests 47(1) 137-144.
 * Karavaiev V. 1912. Ameisen aus dem paläarktischen Faunengebiete. Rus. Entomol. Obozr. 12: 581-596.
 * Karavaiev V. 1927. Myrmekologische Miszellen. Ezheg. Zool. Muz. 27: 104-112.
 * Kupianskaia A.N. 1990. Murav'I (Hymenoptera, Formicidae) Dal'nego Vostoka SSSR (1989). Vladivostok. 258 pages.
 * Kupianskaya A. N., Lelej, A.S., and Urbain, B. K. 2000. The Ants (Hymenoptera: Formicidae) of the Kuril Islands. Far Eastern Entomologist. 92:1-21.
 * Kupianskaya, A. N., Lelej, A.S., and Urbain, B. K. 2000. The Ants (Hymenoptera: Formicidae) of the Kuril Islands. Far Eastern Entomologist. 92:1-21.
 * Kupianskaya, A.N., A.S. Lelej and B.K. Urbain. 2000. The ants (Hymenoptera: Formicidae) of the Kuril Islands. Far Eastern Entomologist 92:1-21
 * Lelej A. S. 2012. Annotated catalogue of the Insects of Russian Far East. Volume 1. Hymenoptera. Dalnauka: Vladivostok. 635 p.
 * Lyu D. P. 2013. Distribution of Ants(Hymenoptera: Formicidae) by Vegetation in Mt. Gariwangsan from Korea. Korean J. Environ. Ecol. 27(2): 204-208.
 * Maruyama M., F. M. Steiner, C. Stauffer, T. Akino, R. H. Crozier, and B. C. Schlick-Steiner. 2008. A DNA and morphology based phylogenetic framework of the ant genus Lasius with hypotheses for the evolution of social parasitism and fungiculture. BMC Evolutionary Biology 8:Article 237 (doi:10.1186/1471-2148-8-237).
 * Mizutani A. 1979. A myrmecofaunal survey at Hiyama Experiment Forest, Hokkaido University. Research Bulletin of the College Experiment Forests, Hokkaido University 36:509-516.
 * Mizutani A. 1979. A myrmecofaunal survey at Hiyama Experiment Forest, Hokkaido University. Research Bulletins of the College Experiment Forests Hokkaido University 36(2): 509-516.
 * Paik W.H. 1984. A checklist of Formicidae (Hymenoptera) of Korea. Korean J. Plant Prot. 23(3): 193-195.
 * Park, Seong, Joon and Byung, and Kim, Jin. 2002. Faunal Comparison of Ants among Cheongsando and Other Islands of South Sea in Korea. Korean Jornal of Entomology. 32(1):7-12.
 * Radchenko A. 2005. A review of the ants of the genus Lasius Fabricius, 1804, subgenus Dendrolasius Ruzsky, 1912 (Hymenoptera: Formicidae) from east Palaearctic. Annales Zoologici (Warsaw) 55: 83-94.
 * Radchenko, A. 2005. Monographic revision of the ants (Hymenoptera, Formicidae) of North Korea. Annales Zoologici 55(2): 127-221.
 * Terayama M. 1992. Structure of ant communities in East Asia. A. Regional differences and species richness. Bulletin of the Bio-geographical Society of Japan 47: 1-31.
 * Terayama M., K. Ogata, and B.M. Choi. 1994. Distribution records of ants in 47 prefectures of Japan. Ari (report of the Myrmecologists Society of Japan) 18: 5-17.
 * Terayama. M. 2004. Geological and ecological distribution of Japanese ants communities. (translated from Japanese) Reports of the Saitama Prefecture Animal Research Association. 48:24
 * Teruyama. M. 1988. Ant fauna of Saitama Prefecture, Japan. ARI Reports of the Myrmecologists Society (Japan) 16: 4-13
 * Wheeler W. M. 1928. Ants collected by Professor F. Silvestri in Japan and Korea. Bollettino del Laboratorio di Zoologia Generale e Agraria della Reale Scuola Superiore d'Agricoltura. Portici 22: 96-125.
 * Wilson E. O. 1955. A monographic revision of the ant genus Lasius. Bulletin of the Museum of Comparative Zoology 113: 1-201
 * Yamauchi K. 1979. Taxonomical and ecological studies on the ant genus Lasius in Japan (Hymenoptera: Formicidae). I. Taxonomy. Sci. Rep. Fac. Educ. Gifu Univ. (Nat. Sci.) 6: 147-181.
 * Yamauchi K., and K. Hayashida. 1968. Taxonomic studies on the genus Lasius in Hokkaido, with ethological and ecological notes (Formicidae, Hymenoptera). I. The subgenus Dendrolasius or Jet Black Ants. J. Fac. Sci. Hokkaido Univ. Ser. VI. Zool. 16: 396-412.