Ponera terayamai

Ponera terayamai has been found in mature forest habitats at middle to high elevation (1777 to 2085 m elevation). Specimens have been collected in Winkler samples and pitfall traps.

Identification
Leong et al. (2019) - Worker: Ponera terayamai can be easily distinguished by the combination of the following characters: in Ponera terayamai, (1) the clypeus presents an acute anterior margin, (2) in dorsal view, the petiolar node is not forming an arch and has an anterior margin almost straight, (3) the dorsum of the petiolar node forms an arch in lateral view and has a posterior margin broadly convex, (4) the antennal scape is short; far to reach the posterior margin of head, and (5) the third abdominal tergum distinctly longer than broad. Although Ponera terayamai presents similarities with Ponera bishamon, both species can be distinguished by the shape of their petiolar node and body size; when observed in lateral view, the petiolar node of Ponera terayamai is subtrapezoidal with a clearly convex posterior margin, while Ponera bishamon has a rectangular petiolar node with a slightly convex posterior margin. In dorsal view, the petiolar node of Ponera terayamai is relatively broader than Ponera bishamon. Ponera terayamai is also larger (HW: 0.43–0.47 mm; n=12) than Ponera bishamon (HW: 0.38–0.39 mm; n=4 with single type worker included). Moreover, Ponera terayamai presents a relatively acute tooth on its clypeus which is less developed in Ponera bishamon.

Distribution based on Regional Taxon Lists
Oriental Region: Taiwan.

Nomenclature

 *  terayamai. Ponera terayamai Leong, Guenard, Shiao & Lin, 2019: 65, figs. 59-64 (w.q.) TAIWAN.

Worker
Holotype: HL 0.56; HW 0.44; SL 0.36; A06L 0.02; A07L 0.02; A08L 0.04; A09L 0.06; A10L 0.07; PrW 0.33; WL 0.73; PeH 0.33; PeNL 0.20; PeW 0.25; ATL 0.45; ATW 0.39; CI 78, SI 83, PeI 76, LPeI 61, DPeI 162, ATI 116.

Paratype workers (n=11): HL 0.53–0.57; HW 0.43–0.47; SL 0.32–0.38; A06L 0.02; A07L 0.02; A08L 0.04; A09L 0.06; A10L 0.08; PrW 0.32–0.35; WL 0.68–0.76; PeH 0.33–0.36; PeNL 0.18–0.21; PeW 0.24–0.27; ATL 0.44–0.48; ATW 0.38–0.44; CI 76–82, SI 73–86, PeI 72–83, LPeI 53–58, DPeI 143–178, ATI 106–117.

Head. In full-face view, head subrectangular and distinctly longer than broad (CI: 76–82), with slightly convex posterior margin and lateral margins, rounded posterolateral corner. Eye small; composed of a total of 4 to 5 indistinct facets. Anterior clypeal margin with acute medial tooth. Masticatory margin of mandible with a series of about 11 to 12 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 = 1.08: 1.96: 2.74: 3.56 (n=12).

Mesosoma. Mesosomal dorsum in lateral view straight. Pronotum in dorsal view arched, with slightly convex lateral margins of pronotum. Metanotal groove weakly incised, with fine suture. Lateral mesopleural suture weakly incised. Propodeal dorsum broad, with straight lateral margins. Posterodorsal corner of propodeum rounded, propodeal dorsum and declivity forming approximatively a 120 degree angle.

Metasoma. Petiolar node in dorsal view trapezoidal and distinctly broader than long, with almost straight anterior margin, slightly concave posterior margin, and slightly convex lateral margins. Petiolar node in lateral view moderately thick and subtrapezoid, with straight anterior margin, broadly convex posterior margin, and dorsum forming an arch. Subpetiolar process with median-sized and oval fenestra, anteroventral corner blunt, ventral margin straight, with a series of indistinct denticles, and posteroventral corner concave with a pair of small teeth. Third abdominal tergum distinctly longer than broad (ATI: 106–117), with slightly convex anterior margin and straight lateral margins.

Sculpture. Head densely punctate. Mandible sparsely punctate. Mesosomal dorsum evenly punctate, but scattered on propodeum. Mesopleuron striate; more densely striate in its lower portion. Metapleuron and lateral face of propodeum striate; with denser striae present on the lower portion. Propodeal declivity smooth. Lateral face of petiole sparsely punctate, smooth posterior face, dorsum with few punctures. The third and fourth abdominal segments evenly punctate, other segments smooth and shining with few punctures.

Pubescence. Head, antennae, mesosoma and gaster with dense short hairs. Mesopleuron, metapleuron and propodeum with few short hairs. Dorsal and ventral faces of head, anterior margin of clypeus, sides of mandibles, dorsum of petiolar node, gastral sterna and posterior half of gastral terga 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
Paratype (n=2): HL 0.58–0.61; HW 0.47–0.50; SL 0.40–0.41; A06L 0.02; A07L 0.02; A08L 0.05; A09L 0.06; A10L 0.08; PrW 0.42–0.43; WL 0.88–0.92; PeH 0.39; PeNL 0.21–0.22; PeW 0.30; ATL 0.54–0.56; ATW 0.49–0.50; CI 81–83, SI 82–85, PeI 70–71, LPeI 54–57, DPeI 133–142, ATI 110–112.

Head. Similar to worker caste, but with large and rounded Eye; maximum diameter of each eye about 0.10 mm with 8 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 = 1.11: 2.20: 2.92: 3.89 (n=2).

Mesosoma. Mesosomal dorsum in lateral view convex. Pronotum in dorsal view arched, with distinctly convex anterior margin, and convex lateral margins. Scutum subtrapezoidal and strongly narrow posteriad, with convex anterior margin, and slightly convex posterior margin. Transcutal suture distinct. Scutellum oval. Anapleural sulcus weakly incised. Propodeal-metapleural suture incised. Propodeal dorsum in dorsal view broad, with right posterolateral corner, and straight posterior margin. Propodeal corner almost forming a sub-right angle.

Metasoma. Petiolar node in dorsal view thin and subrectangular; strongly broader than long, with almost straight anterior and posterior margins, and convex lateral margins. Petiolar node in lateral view thin and subtriangular, with straight anterior margin, and moderately convex posterior margin. Subpetiolar process with middle and circular fenestra, anteroventral corner blunt, ventral margin slightly concave, and posteroventral corner concave with strong and acute teeth. The third abdominal segment similar to worker caste (ATI: 110–112).

Sculpture. Similar to worker caste.

Pubescence. Mostly like worker caste, except for metapleuron and propodeum with scattered short decumbent hairs.

Color. Similar to worker caste.

Type Material
Holotype. Worker: TAIWAN. 1777 to 1787 m alt., Fenghuang Shan, Xitou, Nantou county, 18 X 2016, via Winkler extractor, PC Hsu leg (: CMPon163).

Paratypes (12 workers and 2 dealate queens). TAIWAN. 3 workers, same collection data as holotype (: CMPon159, CAS: CMPon160, : CMPon164). 1 worker, 23.6592°N; 120.8074°E, 1786 m alt., Fenghuang Shan, Xitou, Nantou county, 12I2016, via Winkler extractor, PC Hsu leg (: CMPon019). 1 worker, 23.6595°N; 120.8074°E, 1787 m alt., Fenghuang Shan, Xitou, Nantou county, 12 I 2016, via Winkler extractor, PC Hsu leg (: CMPon021). 1 worker, 23.6592°N; 120.8074°E, 1786 m alt., Fenghuang Shan, Xitou, Nantou county, 15 II 2016, via Winkler extractor, PC Hsu leg (: CMPon022). 1 dealate queen, 23.6598°N; 120.8057°E, 1777 m alt., Fenghuang Shan, Xitou, Nantou county, 22 III 2016, via Winkler extractor, PC Hsu leg (: CMPon018). 5 workers and 1 dealate queen, ca. 1400 m alt., Fenchihu, Chiayi county, 8 X 1994, WH Tsai leg (: CMPon006; : CMPon007, CAS: CMPon008; : CMPon009; HKUBM: CMPon011; : CMPon014).

The type specimens of P. terayamai were collected in five separate Winker samples from leaf litter in primary forest. In Xuejian Recreation area, additional specimens were collected with pitfall traps. Other paratypes are from Fenchihu (ca. 1400 m; primary forest) but without further information on habitat type. While this species was collected with both Winkler extractors and pitfall traps, Winkler extractors seem most useful to collect this cryptobiotic ant.

Etymology
The specific name is given in honor of the Japanese entomologist, Dr. Mamoru Terayama for his contribution to the myrmecological research in Taiwan and the taxonomic study of Ponera.

References based on Global Ant Biodiversity Informatics

 * 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.