Temnothorax basara

The type specimens were collected with 3 larvae from a rotting fallen tree the part of which was buried in the soil (Terayama and Onoyama 1999).

Identification
Terayama and Onoyama (1999) - Total length of workers around 2 mm. Body color yellow. Scapes reaching posterior margin of head in full-face view. Metanotal groove not incised dorsally. Dorsum of propodeum straight in profile; propodeal spines very long and thin, directing much upwards. Petiole with relatively long peduncle, node reverse U-shaped; anterior margin of node much more steeply sloping than posterior margin. Dorsum of mesosoma densely punctulate, without rugae.

This species resembles Temnothorax indra from Okinawa I., and Temnothorax confucii from Taiwan. However, it is distinguished from the latter two by the absence of rugae on the mesosomal dorsum, the much more steeply sloping anterior margin of the petiolar node, the more upwardly directing propodeal spines, and the small body size.

Distribution
Ishigaki I., Iriomote I.

Distribution based on Regional Taxon Lists
Palaearctic Region: Japan.

Nomenclature

 *  basara. Leptothorax basara Terayama & Onoyama, 1999: 80, fig. 19 (w.) JAPAN. Combination in Temnothorax: Bolton, 2003: 271.

Worker
Holotype. HL 0.57 mm; HW 0.47 mm· CI 82; SL 0.44 mm; SI 94; WL 0.63 mm; PW 0.33 mm; PtW 0.15 mm; PtH 0.18 mm; TL 2.1 mm.

Head 1.2 times as long as wide, with slightly convex posterior margin in full-face view; sides behind eyes a little conversing posteriorly. Mandibles longitudinally rugulose. Median clypeal lobe weakly produced; anterior margin evenly convex. Antennae with 12 segments; scapes relatively long, reaching posterior margin of head in full-face view. Eyes moderate in size, maximum diameter 0.12 mm, with about 10 facets in the longest row.

Promesonotal dorsum slightly convex in profile. Metanotal groove not incised dorsally. Dorsum of propodeum straight in profile; propodeal spines long and thin, directing much upwardly and their dorsal margin forming an angle of 120 degrees with propodeal dorsum in side view.

Petiole with relatively long peduncle; node reverse U-shaped; anterior margin of node much more steeply sloping than posterior margin. Subpetiolar process present, but small. Postpetiolar node nearly as long as high, with convex dorsal margin; in dorsal view 1.4 times as wide as long.

Head and mesosoma densely punctulate, without distinct rugae; petiole and postpetiole more weakly punctulate; gaster smooth and shining.

Head dorsum with erect hairs; mesosomal dorsum with about 18 erect hairs which are longer than those on head dorsum; petiole with 2 pairs, postpetiole with 3 pairs of erect hairs; gaster with scattered erect to suberect hairs.

Body color yellow.

Type Material
Holotype. Worker, Shirahama, Iriomote I., Okinawa Pref., 23.III.1975, K. Onoyama leg. Paratypes. 2 workers, same data as holotype.

Determination Clarifications
This species corresponds to Leptothorax sp. B. of Onoyama (1976) and Leptothorax sp. 12 of Terayama et al. (1992).