Strumigenys strigatella

A rare species, found on several occasions in big chinquapin tree trunks at a wood-chipping factory, and from natural forests (Japanese Ant Image Database).

Identification
Bolton (2000) - A member of the godeffroyi complex in the Strumigenys godeffroyi-group. See notes under Strumigenys confusatrix. This species is unique in the Japanese fauna as it is the only one to combine a mostly or entirely reticulate-punctate lateral alitrunk with long dense basigastral costulae.

Japan
This species is similar to Strumigenys lewisi in general appearance, but separable in having fine punctures on the mesopleuron and lateral surfaces of the propodeum, and by the shape of its head (Japanese Ant Image Database).

Distribution based on Regional Taxon Lists
Palaearctic Region: Japan.

Nomenclature

 *  strigatella. Strumigenys strigatella Bolton, 2000: 798 (w.q.) JAPAN.

Worker
Holotype. TL 2.3, HL 0.61, HW 0.41, CI 67, ML 0.27, MI 44, SL 0.34, SI 83, PW 0.26, AL 0.64. Characters of godeffroyi-complex. Cephalic dorsum with 4-6 erect hairs present close to occipital margin, these hairs simple or minutely looped at apex. With head in full-face view the dorsolateral margin posterior to the flagellate apicoscrobal hair has a row of 2-3 stiffly projecting hairs. These hairs contrast with the marginal hairs anterior to the flagellate hair as they are more cylindrical (i.e. not spatulate), more elevated and less strongly curved anteriorly. Ground-pilosity on pronotal dorsum sparse and inconspicuous. Dorsum of pronotum with a pair of erect flagellate hairs as well as the humeral pair; pronotal dorsum reticulate-punctate with a few superimposed weak longitudinal rugulae. Entire side of alitrunk densely reticulate-punctate, or katepisternum with a small smooth patch. Propodeal declivity with a broad conspicuous lamella. Propodeal teeth weakly represented at dorsal apex of lamella, fully confluent with lamella; in profile dorsal surface of tooth not surmounted by a convex crest or ridge of spongiform tissue or at most with a sliver of such tissue present. Disc of postpetiole with superficial punctulate and costulate sculpture; not entirely smooth nor entirely densely reticulate-punctate. Pilosity of first gastral tergite of flagellate or looped fine hairs. Basigastral costulae fine, dense and long, extending about half the length of the tergite, spaces between costulae superficially shagreenate.

Paratypes. TL 2.3-2.6, HL 0.60-0.65, HW 0.41-0.45, CI 67-70, ML 0.26-0.30, MI 43-46, SL 0.34-0.37, SI 81-84, PW 0.25-0.30, AL 0.64-0.73 (6 measured). Paratypes from Yona have the disc of the postpetiole more feebly sculptured and the basigastral costulae fainter than those from Ootomi.

Type Material
Holotype worker, Japan: Okinawa Pref., Iriomote I., Ootomi, n. M. 88, w 850806 #11, no. 6596 (K. Yamauchi & K. Kinomura).

Paratypes. 2 workers with same data as holotype but nos. 6595, 6597; 1 queen and ca 25 workers (many in alcohol, Onoyama vial #4), Okinawa Pref., Okinawa I., Yona, 6.ix.1984 (F. Sato) (OMNH,, and in private collections of Onoyama, Ogata and Hashimoto).

References based on Global Ant Biodiversity Informatics

 * Terayama M., S. Kubota, and K. Eguchi. 2014. Encyclopedia of Japanese ants. Asakura Shoten: Tokyo, 278 pp.