Strumigenys lacunosa

This species is rare in Japan - with only one record to data, from the floor of broadleaf forest in northern Okinawa Island (Japanese Ant Image Database).

Identification
Bolton (2000) - A member of the caniophanes complex in the Strumigenys caniophanes-group. See notes under Strumigenys dipsas.

Japan
The absence of subapical teeth on the mandibles is unique to this species among Japanese Strumigenys, so that it is easily distinguished from the others (Japanese Ant Image Database).

Distribution based on Regional Taxon Lists
Oriental Region: Taiwan. Palaearctic Region: Japan.

Nomenclature

 *  lacunosa. Strumigenys lacunosa Lin & Wu, 1996: 146, figs. 5, 11, 20-24 (w.q.) TAIWAN. See also: Bolton, 2000: 759.

Worker
Bolton (2000) - TL 3.1, HL 0.78, HW 0.57, CI 73, ML 0.39, MI 50, SL 0.43, SI 75, PW 0.33, AL 0.84. Mandible with a preapical tooth, reduced to a large denticle in some individuals. Dorsolateral margin of head in full-face view with 3 freely laterally projecting flagellate hairs: one just posterior to level of eye, one in apicoscrobal position, one posterior to this on dorsolateral margin of occipital lobe. Cephalic dorsum with a transverse row of 4-6 erect fine hairs along occipital margin but without erect hairs anterior to this. Dorsum of head weakly finely reticulate-rugulose and densely reticulate-punctate. Apical funicular segment moderately constricted basally. Pronotal dorsum sharply punctate, side of pronotum less regularly sculptured. Pleurae and side of propodeum mostly smooth, some sculpture present above level of propodeal spiracle. Pronotal humeral hair flagellate and very long. Dorsum of pronotum with at least 2 pairs of erect flagellate hairs, and about 4 pairs present on mesonotum. First gastral tergite with numerous long fine flagellate hairs. Dorsal and ventral surfaces of hind femur with spaced rows of standing hairs; dorsal (outer) surfaces of hind tibia and basitarsus each with long erect freely projecting filiform or flagellate hairs. Propodeal teeth acute, in profile short-triangular and broad basally. Petiole in profile claviform, the lateral spongiform lobe large; in dorsal view the lateral spongiform lobes extend forward to level of anterior face of node where node grades into peduncle.

Type Material
Bolton (2000) - Holotype worker, paratype workers and queen, TAIWAN: Taipei Hsien, Chuchih, 26.v.1988 (C. -C. Lin); paratype workers and queens, TAIWAN: Nantou Hsien, Chitou, 29.xi.1992 (C. -C. Lin); Lienhuachih, 31.x.1988 (Y. C. Shiau); Taitung Hsien, Lichia, 29.iii.1995 (C. -C. Lin) [examined].

Etymology
Refers to lacunose sculptures on the head, mesosoma, petiole and postpetiole.

References based on Global Ant Biodiversity Informatics

 * Bolton, B. 2000. The Ant Tribe Dacetini. Memoirs of the American Entomological Institute 65
 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Hu C.-H. 2006. Indigenized conservation and biodiversity maintenance on Orchid Island. PhD Thesis, graduate school of the University of Minnesota. 150 pages.
 * Lin C.C., and W.J. Wu. 1996. Revision of the ant genus Strumigenys Fr. Smith (Hymenoptera: Formicidae) of Taiwan. Chinese Journal of Entomology 16:137-152.
 * Terayama M. 2009. A synopsis of the family Formicidae of Taiwan (Insecta: Hymenoptera). Research Bulletin of Kanto Gakuen University. Liberal Arts 17:81-266.
 * Terayama M., S. Kubota, and K. Eguchi. 2014. Encyclopedia of Japanese ants. Asakura Shoten: Tokyo, 278 pp.
 * Terayama Mamoru. 2009. A synopsis of the family Formicidae of Taiwan (Insecta, Hymenoptera). The Research Bulletin of Kanto Gakuen University 17: 81-266.
 * Terayama, M. 2009. A synopsis of the family Formicidae of Taiwan (Insecta; Hymenoptera). The Research Bulletin of Kanto Gakuen University 17: 81-266.
 * 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.; Ikudome, S.; Terayama, M. 1999. Identification guide to the Aculeata of the Nansei Islands, Japan. Sapporo: Hokkaido University Press, xii + 831 pp. pp138-317.