Strumigenys takasago

AntWiki: The Ants --- Online
Strumigenys takasago
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Myrmicinae
Tribe: Attini
Genus: Strumigenys
Species: S. takasago
Binomial name
Strumigenys takasago
(Terayama, Lin & Wu, W.-J., 1995)

Pyramica takasago side (www.niaes.affrc.go.jp).jpg

Pyramica takasago top (www.niaes.affrc.go.jp).jpg

Specimen labels

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.

Tang & Guenard (2023) - Specimens from Guangxi Province of mainland China (Fig. 39D–F) have propodeal spines that are slightly broader and less developed than those of the specimens from Taiwan (Fig. 39G–I), and not armed at a distinct upward angle; the specimens from Guangxi (TL 2.0, ML 0.49–0.50) are also slightly smaller than those from Taiwan (TL 2.2–2.3, ML 0.55–0.60). No other major morphological difference is observed; hence, we consider specimens from Guangxi as S. takasago. This is the first record of the species within continental Asia, indicating it is not endemic to Taiwan.

  • Tang & Guenard (2023), Fig. 39. New species records of Strumigenys in full-face, profile and dorsal views. A–C. Worker of S. sydorata from Hainan, mainland China (HNA-00781). D–F. Worker of S. takasago from Guangxi, mainland China (ANTWEB1011895). G–I. Worker of S. takasago from Taiwan (ANTWEB1010910(1)).

Keys including this Species

Distribution

Distribution based on Regional Taxon Lists

Oriental Region: Taiwan (type locality).
Palaearctic Region: China.

Distribution based on AntMaps

AntMapLegend.png

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.
pChart

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.
pChart

Biology

Castes

Pyramica takasago mesosoma (www.niaes.affrc.go.jp).jpg
.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

  • 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.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.

Description

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) (National Taiwan University, The Natural History Museum) [examined].

References

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.
  • 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., C. C. Lin, and W. J. Wu. 1995. The ant genera Epitritus and Kyidris from Taiwan (Hymenoptera: Formicidae). Proceedings of the Japanese Society of Systematic Zoology 53: 85-89.
  • Terayama, M. 2009. A synopsis of the family Formicidae of Taiwan (Insecta; Hymenoptera). The Research Bulletin of Kanto Gakuen University 17: 81-266.
  • Xu Z. H., and X. G. Zhou. 2004. Systematic study on the ant genus Pyramica Roger (Hymenoptera, Formicidae) of China. Acta Zootaxonomica Sinica 29: 440-450.
  • Xu Z. and X.-G. Zhou. 2004. Systematic study on the ant genus Pyramica Roger (Hymenoptera, Formicidae) of China. Acta Zootaxonomica Sinica 29(3): 440-450