Strumigenys takasago

Kknown only from the type-collection.

Identification
A member of the Strumigenys mutica-group. S. takasago differs from all other group members in these regions by possessing small triangular propodeal teeth and having a number of short spatulate hairs on the leading edge of the scape that curve toward the base of the scape. Propodeal teeth also occur in the Malagasy Strumigenys tathula but otherwise these features are absent in other species of the group. The presence of the basally curved scape hairs separates takasago from its closest relatives in the key.

Specialised standing pilosity is as sparse here as elsewhere in the group, with only one pair on each of the following: vertex, mesonotum, petiole, postpetiole. The first gastral tergite has two pairs.

Terayama et al. (1995) - The present species is easily distinguished from the other congeners by the presence of standing spoon-shaped hairs on 1st to 3rd gastral tergites and acute propodeal spines in worker, and presence of standing spoon-shaped hairs on mesonotum, postpetiole, and 1st to 3rd gastral tergites in female.

Distribution based on Regional Taxon Lists
Oriental Region: Taiwan.

Nomenclature

 *  takasago. Kyidris takasago Terayama, Lin & Wu, 1995: 87, figs. 7-9 (w.q.) TAIWAN. Combination in Pyramica: Bolton, 1999: 1672; in Strumigenys: Baroni Urbani & De Andrade, 2007: 128. See also: Bolton, 2000: 456.

Worker
Holotype. H L 0.55 mm; HW 0.43 mm; SL 0.32 mm; ML 0.15 mm; CI 78; SI 74; MI 27; WL 0.55mm; AW 0.31 mm; TL 2.2mm.

Head triangular, with convex posterior border in frontal view; cephalic dorsum microreticulate with many short decumbent hairs; a single pair of standing spoon-shaped hairs at the highest point of the vertex. Mandibles relatively long and moderately arcuate in frontal view, with a series of minute teeth. Clypeus longer than wide, with well convex anterior border; dorsum with many short decumbent hairs. Antennae with 6 segments; scape long, anterior border with a row of spatulate hairs; 2nd segment longer than wide; 3rd and 4th segments each almost as long as wide; 5th broadest at posteriormost, 1.75 x as long as wide; apical segment 4.0 X as long as wide. Eyes small, consisting of 8 omatidia.

General form of alitrunk, petiole and postpetiole as shown in figure; promesonotum with short decumbent hairs sparsely; in dorsal view, anterolateral borders rounded, not forming an angle; posterior portion with a pair of standing spoon-shaped hairs; metanotal groove moderately depressed; propodeum with acute spines dorsolaterally. Petiole long and slender, with a round node; ventral border with a thin long spongiform lamella. Dorsal border of postpetiole broadly rounded. Pedicels each with a pair of standing spoon-shaped hairs.

First gastral tergite with 2 pairs of standing spoon-shaped hairs, one pair on the anterior portion and the other on the posterior portion; 2nd and 3rd tergites each with a row of 4 standing spoon-shaped hairs.

Color yellow.

Paratypes. Ten workers with the following measurements and indices: HL 0.55-0.59 mm; HW 0.50-0.52 mm; SL 0.33-0.35 mm; ML 0.15-0.16 mm; CI 85-95; SI 63-70; MI 25-29; WL 0.56-0.60mm; AW 0.33-0.35mm; TL 2.2-2.3mm. Female. HL 0.70mm; HW 0.63mm; SL 0.43mm; ML 0.17mm; CI 90; SI 68; MT 24; WL 0.93mm; AW 0.47mm; TL 2.9mm.

General shape of head as in worker with the usual caste differences. Alitrunk in profile with gently convex dorsal border; promesonotum and scutellum with many short decumbent hairs; 3 pairs of standing spoon-shaped hairs present on mesonotum; mesopleura smooth and shining; propodeum smooth and shining, with dull angulations posterodorsally; propodeal lamellae weakly developed. Petiole long, wish round node; ventral border with a low spongeform appendage. Postpetiole with a pair of standing spoon-shaped hairs.

First gastral tergite with 2 pairs of standing spoon-shaped hairs, one at anterior portion and the other at near posterior border. Second and 3rd gastral tergites each with a transverse row of 4 standing spoon-shaped hairs.

Color yellow.

Type Material
Holotype: Worker, Huisunlinchang, Nantou Hsien, 14.XI.1992, C.C. Lin leg. Paratypes: One female, 170 workers, same colony as holotype. The holotype is deposited in the collection of the National Institute of Agro-Environmental Sciences, Tsukuba, Japan, and paratypes in the Taiwan Agricultural Research Institute, Taichung, and the National Taiwan University, Taipei.

Bolton (2000) - Holotype worker, paratype workers and queen, TAIWAN: Huisunlinchang, Nantou Hsien, 14.xi.1992 (C. -C. Lin) [examined].