Lasius hayashi

This species nests in dead portions of tree trunks, especially at or near the roots. Nuptial flights occur in July and August (Japanese Ant Image Database).

Identification
Japanese Ant Image Database - Total length of workers around 2 - 4 mm. Head and mesosoma light brown, gaster dark brown. Antennal scapes usually slightly shorter than the head width, and with erect hairs. Petiole high, its tip acutely angulate; anterior margin of petiolar scale not angulate.

Seifert (2020) - Lasius hayashi is separable from the sympatric and similarly hirsute Lasius japonicus by its broader head, shorter scape, more convex petiole sides and a homogenously yellowish brown head capsule.

Distribution
Upper-altitudinal occurence records: 600 m at 44°N in Hokkaido and 1600 m at 34°N in Shikoku.

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

Biology
Seifert 2020, summarizing Yamauchi 1979 and Yamauchi, Ito, Suzuki 1986 - Main habitat is shady deciduous woodland with large trees. The nests are mostly constructed within the root systems or in hollow trunks of trees and sometimes in rotten logs and may contain carton structures. Being active in Sapporo to mid November, L. hayashi has a longer foraging season than sympatric congeneric species. The foraging paths are almost completely covered by macerated plant and humus material both on tree trunks and on the ground near the tree where trophobiotic Homoptera are tended. Flights were observed from early July to late August and start in the late evening at light intensities of only 0–10 lux and air temperatures of 22– 24°C. Air movements and rain stop the flight.

Nomenclature

 *  hayashi. Lasius hayashi Yamauchi & Hayashida, 1970: 510, figs. 1, 5, 7, 8, 11 (w.q.m.) JAPAN. See also: Collingwood, 1976: 305; Yamauchi, 1979: 158; Kupyanskaya, 1990: 220; Seifert, 1992b: 45.

Worker
Seifert (2020) - Large (CS 994 µm). Head shorter than in other sympatric species (CL/CW900 1.049) and usually with concave posterior margin. Scape rather short (SL/CS900 0.978). Postocular distance medium and eye rather small (PoOc/ CL900 0.241, EYE/CS900 0.230). Torulo-clypeal distance rather large (dClAn900 5.07). Number of mandibular dents rather low (MaDe 7.95). Terminal segment of maxillary palp rather long (MP6/CS900 0.194). Pubescence on clypeus moderately dense (sqPDCL900 4.59); on frons rather short (PLF900 28.4); on scape subdecumbent to suberect and difficult to distinguish from shorter setae; on hind tibia decumbent to appressed, contrasting the situation in the long, suberect to erect setae. Gular and pronotal setae long (GuHL/CS900 0.114, PnHL/CS900 0.154). Whole body covered by numerous standing setae (nOcc900 13.1, nGen900 5.1, nGu900 6.4, nSc900 18.3, nHT900 17.4, nSt900 4.9). Coloration: mesosoma, petiole, scape, femora and tibiae pale yellowish brown, head darker yellowish brown, gaster blackish brown or dark brown with yellowish tinge.

See table 11 in Seifert 2020 for additional morphometrics. The abbreviated names of various quantitative data shown above are defined here: Seifert 2020 Lasius characters.

Type Material
Seifert (2020) - One paratype worker from the holotype nest series labelled ”Sapporo Hokkaido 27-VII-1967 K. Yamauchi“; depository.

References based on Global Ant Biodiversity Informatics

 * Anonymous. A list of ants collected at Bandai, Fukushima Prefecture by the members of the Myrmecological Society of Japan in 1992. ARI Reports of the Myrmecologists Society (Japan) 18: 31
 * 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., 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:
 * Eto S., and K. Ogata. 1983. Ants of Hirado Island, Kyushu. Bulletin of the Nagasaki Prefecture Biological Group 25: 7-11.
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Harada Y., K. Nishikubo, K. Matsumoto, M. Matsuda, Y. Inazawa, Y. Ozono, S. Koto, N. Kawaguchi, and S. Yamane. 2011. Ant fauna of Japanese beech (Fagus crenata) forests in southwestern Japan. Bull. Biogeogr. Soc. Japan 66: 115-127.
 * Harada Y., Yadori H., Takinami R., Nagahama K., Matsumoto Y., Oyama A., Maeda S. and Yamane S.K. 2013. Ants of the southernmost Fagus crenata forest in Japan. Nature of Kagoshima 39: 113-118
 * Hayashida K. 1971. Vertical distribution of ants in the southern part of the Hidaka mountains. [In Japanese.]. Memoirs of the National Science Museum (Tokyo) 4:29-38.
 * 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.
 * Hosoichi S., M. Yoshimura, Y. Kuboki, and K. Ogata. 2007. Ants from Yakushima Island, Kagoshima Prefecture. Ari 30: 47-54.
 * Hosoishi S., M. Yoshimura, Y. Kuboki, and K. Ogata. 2007. Ants from Yakushima Island, Kagoshima Prefecture. Ari 30: 47-54.
 * 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.
 * Ikeshita Y., A. Gotoh, K. Yamamoto, N. Taniguchi, and F. Ito. 2007. Ants collected in Mt. Linoyama, Marugame, Kagawa Prefecture (Hymenoptera, Formicidae). Kagawa Seibutsu 34: 59-62.
 * Johnson R. Personnal Database. Accessed on February 5th 2014 at http://www.asu.edu/clas/sirgtools/resources.htm
 * Kim B.J. 1996. Synonymic list and distribution of Formicidae (Hymenoptera) in Korea. Entomological Research Bulletin Supplement 169-196.
 * Kim B.J., S.J. Park, and J.H. Kim. 1996. Ants from Naejangsan national park (Hymenoptera: Formicidae). Korean J. Soil. Zoology &(2): 120-133.
 * Kim C.H.; Choi, B.M. 1987. On the kinds of ants (Hymenoptera: Formicidae) and vertical distribution in Jiri Mountain. Korean Journal of Plant Protection 26:123-132.
 * 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.
 * Lelej A. S. 2012. Annotated catalogue of the Insects of Russian Far East. Volume 1. Hymenoptera. Dalnauka: Vladivostok. 635 p.
 * Maeto K. and S. Sato. 2004. Impacts of forestry on ant species richness and composition in warm-temperate forests of Japan. Forest Ecology and Management 187: 213223.
 * 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.
 * Ogata. K., Touyama, Y. and Choi, B. M. 1994. Ant fauna of Hiroshima Prefecture, Japan. ARI Reports of the Myrmecologists Society (Japan) 18: 18-25
 * Paik W.H. 1984. A checklist of Formicidae (Hymenoptera) of Korea. Korean J. Plant Prot. 23(3): 193-195.
 * Park S.J., and B.J. Kim. 2002. Faunal comparison of ants among Cheongsando and other islands of South Sea in Korea. Korean Journal of Entomology 32(1): 7-12.
 * 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. Monographic revision of the ants (Hymenoptera: Formicidae) of North Korea. Annales Zoologici (Warsaw) 55: 127-221.
 * Radchenko, A. 2005. Monographic revision of the ants (Hymenoptera, Formicidae) of North Korea. Annales Zoologici 55(2): 127-221.
 * Ran H., and S. Y. Zhou. 2012. Checklist of chinese ants: formicomorph subfamilies (Hymenoptera: Formicidae) II. Journal of Guangxi Normal University: Natural Science Edition 30(4): 81-91.
 * Sato T., N. Tsurusaki, K. Hamaguchi, and K. Kinomura. 2010. Ant fauna of Tottori prefecture, Honshu, Japan. Bulletin of the Tottori Prefectural Museum 47: 27-44.
 * Seifert B. 1992. A taxonomic revision of the Palaearctic members of the ant subgenus Lasius s.str. (Hymenoptera: Formicidae). Abhandlungen und Berichte des Naturkundemuseums Görlitz 66(5): 1-67.
 * Sonobe R. 1971. Ant survey of the Mt. Daisetsu area. Faunal Survey of the Mt. Daisetsu area. JIBP main area XIV. Annual Report of JIBP/CT-S: 199-210.
 * Terayama M. 1983. Kagoshima-ken-hondo no ari. Kanagawa-chucho (Journal of the Kanagawa Entomologists Association): 13-24.
 * 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. 1994. Ants of Okushiri-to Island, Hokkaido. Ari 18: 28-29.
 * Terayama M., Choi, B.M., Kim, C.H. 1992. A check list of ants from Korea, with taxonomic notes. Bulletin of the Toho Gakuen 7:19-54.
 * 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., S. Kubota, and K. Eguchi. 2014. Encyclopedia of Japanese ants. Asakura Shoten: Tokyo, 278 pp.
 * Terayama M., and S. Kubota. 2002. Ants of Tokyo, Japan. ARI 26: 1-32.
 * Terayama M., and S. Yamane. 1984. Ants of Yaku-shima Island, the northern Ryukyus, with reference to their altitudinal distribution (Insecta: Hymenoptera). Cons. Rep. Yaku-shima Wildness Area, Kyushu, Japan, pp. 643-667. Nat. Cons. Bureau, Env. Agency, Japan.
 * Terayama. M. 1994. Ants of Okushiri-to Island, Hokkaido. ARI Reports of the Myrmecologists Society (Japan) 18: 28-29
 * Terayama. M. 2004. Geological and ecological distribution of Japanese ants communities. (translated from Japanese) Reports of the Saitama Prefecture Animal Research Association. 48:24
 * Terayama. M. 2004. Geological and ecological distribution of Japanese ants communities. (translated from Japanese) Reports of the Saitama Prefecture Animal Research Association. 48:34
 * Teruyama. M. 1988. Ant fauna of Saitama Prefecture, Japan. ARI Reports of the Myrmecologists Society (Japan) 16: 4-13
 * Touyama Y., T. Yamamoto, and N. Nakagoshi. 2001. Myrmecofauna at gap site in Beech forest, seven years after typhoon disturbance. Adapholgia 67: 15-22.
 * Yamane S., S. Ikudome, and M. Terayama. 1999. Identification guide to the Aculeata of the Nansei Islands, Japan. Sapporo: Hokkaido University Press, xii + 831 pp. pp, 138-317.
 * Yamane S., Y. Harada, and K. Eguchi. 2013. Classification and ecology of ants. Natural history of ants in Southern Kyushu. 200 pages
 * Yamane S.; Ikudome, S.; Terayama, M. 1999. Identification guide to the Aculeata of the Nansei Islands, Japan. Sapporo: Hokkaido University Press, xii + 831 pp. pp138-317.
 * 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. 1970. Taxonomic studies on the genus Lasius in Hokkaido, with ethological and ecological notes (Formicidae, Hymenoptera). II. The subgenus Lasius. J. Fac. Sci. Hokkaido Univ. Ser. VI. Zool. 17: 501-519.
 * Yoshimura M. 1998. Ants from Islands in Hokkaido, Northern Japan (No. 1, Risiri Island). Rishiri Studies 17:33-38.
 * Yoshimura M. 1999. Ants in the island of Hokkaido (Part 2, Part Rebun) Ants from Islands in Hokkaido, Northern Japan (No. 2, Rebun-Island). Rishiri Studies 18: 49-54.
 * Yoshimura M. 2000. Ants in the island of Hokkaido (Part 3, Part ???) Ants from Islands in Hokkaido, Northern Japan (No. 3, Teuri Island). Rishiri Studies 19: 27-35.
 * Yoshimura M. 2007. List of ants collected in Iwate Prefecture During the 49th Myrmecological congress of Japan. Ari 29: 41.