Ponera bishamon

A rare species that nests in soil (Japanese Ant Image Database).

Identification
Terayama (1996) - Unique in having an elongate gaster.

Leong et al. (2019) - worker: This species is characterized by a short antennal scape; a clypeal margin with a blunt tooth; the third abdominal tergum longer than broad; and a petiolar node subtrapezoidal with slightly convex posterior margin. Ponera bishamon is similar to Ponera yuhuang, Ponera taiyangshen, Ponera japonica, Ponera pianmana, and Ponera terayamai, but can be distinguished from Ponera yuhuang, Ponera taiyangshen, Ponera japonica, and Ponera pianmana by its third abdominal tergum longer than broad. In dorsal view, the petiolar node is narrower in Ponera bishamon than in Ponera terayamai, and the medial tooth on the clypeal margin is blunt.

Distribution based on Regional Taxon Lists
Palaearctic Region: Japan.

Nomenclature

 *  bishamon. Ponera bishamon Terayama, 1996: 13, figs. 17-20 (w.) JAPAN.

Worker
Holotype. Worker. HL 0.48 mm; HW 0.38 mm; SL 0.28 mm; CI 79; SI 74; WL 0.58 mm; AW 0.28 mm; PNL 0.18 mm; PH 0.29 mm; DPW 0.23 mm; PNI 78; TL 1.9 mm.

Head slender, 1.27 x as long as wide, with subparallel sides and weakly concave posterior comer in frontal view. Mandibles with 3 apical teeth followed by minute several denticles. Antennae with 12 segments; scape not reaching posterior comer of head; apical 5 segments forming a club. Clypeus with a distinct median tooth. Eyes small, consisting of a single facet only.

Dorsal margin of alitrunk almost straight from the midlength of pronotum to posterior end of propodeum in lateral view; posterodorsal comer of propodeum dully angulate in lateral view. Petiolar node thick; disc 0.40x as long as wide, with concave posterior margin in dorsal view. Subpetiolar process with small and dull posterolateral teeth; fenestra circular.

Gaster long; 1st segment 1.15 x as long as wide in dorsal view; 2nd segment slightly shorter than 1st, 1.0x as long as wide.

Head, antennal scapes and pronotum microreticulate; mesonotum and propodeum moderately punctate; petiole smooth with punctures sparsely; 1st and 2nd gastral tergites moderately punctate.

Body blackish brown; mandibles, antennae and legs yellow.

Leong et al. (2019) - (n=3): HL 0.47–0.49; HW 0.38–0.39; SL 0.30–0.31; A06L 0.02; A07L 0.02; A08L 0.03; A09L 0.05; A10L 0.06; PrW 0.29–0.30; WL 0.64–0.65; PeH 0.30–0.32; PeNL 0.17–0.18; PeW 0.24–0.25; ATL 0.39–0.41; ATW 0.37–0.38; CI 77–84, SI 79, PeI 82–85, LPeI 54–58, DPeI 135–149, ATI 105–109.

Head. In full-face view, head subrectangular and distinctly longer than broad (CI: 77–84), with slightly convex posterior margin, slightly convex lateral margins and broadly rounded posterolateral corners (Fig. 36C). Eye small; composed of a total of 3–4 indistinct facets. Anterior clypeal margin with blunt medial tooth. Masticatory margin of mandible with a series of about 13 indistinct denticles, and three large teeth on the apical part. Antennal scape, when laid backward, with a remaining distance of about 10% of the scape length to the posterolateral corner; average ratio of the length of antennomeres 7/6:8/6:9/6:10/6 = 1.16: 1.97: 3.19: 3.84 (n=3).

Mesosoma. Mesosomal dorsum in lateral view convex. Pronotum in dorsal view with acutely convex anterior margin and moderately convex lateral margins. Metanotal groove distinctly and finely incised. Lateral mesopleural suture superficially incised. Propodeal dorsum in dorsal view broad, with straight lateral margins. Propodeal corner in lateral view angular, propodeal dorsum and declivity forming approximatively a 120 degree angle.

Metasoma. Petiolar node in dorsal view arched, with well convex anterior margin, slightly concave posterior margin, and convex lateral margins. Petiolar node in lateral view moderately thick and subtrapezoid, with straight anterior margin, slightly convex posterior margin, and convex dorsal margin; posterodorsal corner lower than anterodorsal corner. Subpetiolar process with medium and circular fenestra, anteroventral corner blunt, straight ventral margin, and posteroventral corner concave with a pair of small teeth. Third abdominal tergum slightly longer than broad (ATI: 105–109), with moderately convex anterior margin and well convex lateral margins.

Sculpture. Head densely punctate. Mandible sparsely punctate. Pronotum and mesonotum evenly punctate. Mesopleuron evenly striate. Metapleuron with weakly striate lower portion and smooth upper portion. Propodeum with smooth lower portion and evenly punctate upper portion. Propodeal declivity smooth. Lateral face of petiole evenly punctate, posterior face smooth, dorsum sparsely punctate. The third and fourth abdominal segments densely punctate, other segments smooth and shining with few punctures.

Pubescence. Head, antennae, mesosoma, petiole, and gaster with evenly distributed short hairs. Mesopleuron, metapleuron, propodeum and lateral face of petiole with scattered short hairs, but glabrous in the lower portion of propodeum. Dorsal and ventral faces of head, anterior margin of clypeus, sides of mandibles, dorsum of petiolar node and gaster with many long erect hairs. Subpetiolar process with a few long erect hairs.

Color. Body color dark brown. Mandible, clypeus, antennae, legs, and apex of gaster yellowish orange.

Queen
Leong et al. (2019) - (n=1): HL 0.52; HW 0.42; SL 0.31; A06L 0.02; A07L 0.02; A08L 0.04; A09L 0.05; A10L 0.07; PrW 0.36; WL 0.73; PeH 0.34; PeNL 0.17; PeW 0.28; ATL 0.46; ATW 0.44; CI 82, SI 73, PeI 77, LPeI 50, DPeI 163, ATI 105.

Head. Similar to worker caste, but with large and oval Eye, maximum diameter of each eye about 0.09 mm with 7 ommatidia along the maximum diameter. Three ocelli present, and forming an equilateral triangle. Antennal scape similar to worker; average ratio of the length of antennomeres 7/6:8/6:9/6:10/6 = 1.20: 2.47: 3.27: 4.40 (n=1).

Mesosoma. Mesosomal dorsum in lateral view broadly convex. Pronotum in dorsal view with acutely convex anterior margin, and broadly convex lateral margins. Scutum subtrapezoidal, narrow posteriad, with moderately convex anterior margin and straight posterior margin. Transcutal suture distinct and broad. Scutellum suboval. Anapleural sulcus weakly incised. Propodeal-metapleural suture indistinct. Propodeum broad with straight lateral margins. Propodeal corner in lateral view angular; propodeal dorsum and declivity forming approximatively a 115 degree angle.

Metasoma. Petiolar node in dorsal view very thin, broader than long, with broadly convex anterior margin, slightly concave posterior margin. Petiolar node in lateral view subtrapezoidal and thin, with straight anterior margin, and slightly convex posterior margin. Subpetiolar process with small and circular fenestra, anteroventral corner blunt, straight ventral margin, and posteroventral corner concave with a pair of small teeth. The third abdominal segment similar to worker caste (ATI: 105).

Sculpture. Similar to worker caste; except metapleuron and lateral propodeum with increased puncture and striation.

Pubescence. Similar to worker caste; except metapleuron and lateral propodeum with increased short decumbent hairs.

Color. Similar to worker caste.

Etymology
The specific name is the Japanese noun bishamon-ten, which is the name of one of the four guardian deities in buddhism.

References based on Global Ant Biodiversity Informatics

 * Kawahara Y., S. Hosoyamada, and S. Yamane. 1999. Ant fauna of the Terayama Station for Education and Research on Nature, Kagoshima University. Bulletin of the Faculty of Education, Kagoshima University. Natural Science 50: 147-156.
 * Leong C. M., B. Guénard, S. F. Shiao, & C. C. Lin. 2019. Taxonomic revision of the genus Ponera Latreille, 1804 (Hymenoptera: Formicidae) of Taiwan and Japan, with a key to East Asian species. Zootaxa 4594: 1-86.
 * Terayama M. 1996. Taxonomic studies on the Japanese Formicidae, part 2. Seven genera of Ponerinae, Cerapachyinae and Myrmicinae. Nature & Human Activities 1: 9-32.
 * Terayama M., S. Kubota, and K. Eguchi. 2014. Encyclopedia of Japanese ants. Asakura Shoten: Tokyo, 278 pp.
 * 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.