Nylanderia birmana

This species is infrequent in collections and seems to be restricted to the Himalayas. It was encountered underneath a stone along a roadside at Palampur, Himachal Pradesh, and was collected on honey bait in subtropical, semi-evergreen forests of Uttarakhand. (Wachkoo and Bharti 2015)

Identification
Wachkoo and Bharti (2015) - The workers of this species can be immediately recognized from other Southeast Asian congeners by the presence of a microreticulate sculpture on head and mesosoma.

Distribution based on Regional Taxon Lists
Oriental Region: India, Myanmar. Palaearctic Region: China.

Nomenclature

 *  birmana. Prenolepis birmana Forel, 1902d: 291 (w.) MYANMAR. Combination in Paratrechina (Nylanderia): Emery, 1925b: 219; in Nylanderia: LaPolla, Brady & Shattuck, 2010a: 127. Current subspecies: nominal plus hodgsoni.

Worker
Wachkoo and Bharti (2015) - HL 0.67-0.81 mm; HW 0.53-0.65 mm; EL 0.16-0.20 mm; SL 0.81-0.95 mm; PW 0.41-0.48 mm; PrFL 0.67-0.77 mm; PrFW 0.16-0.18 mm; WL 0.86-1.01 mm. Indices: CI 78.01-81.44; SI 140.35-154.16; REL 23.61-24.66 (n = 20).

Head is subrectangular; distinctly longer than wide, equally wide anteriorly and posteriorly, lateral margins gently convex, posterior margin shallowly concave to convex with rounded posterolateral corners. Clypeus subcarinate in the middle; anterior clypeal margin feebly concave to convex. Eyes moderately large, oval, convex, covering approximately three-tenths of lateral cephalic margin; three small ocelli present. Antennae long, scape surpasses posterior margin by more than two-fifths their length.

Metanotal groove strongly developed, in lateral view interrupts the regular promesonotal convexity from propodeum; metanotal area distinct. Dorsal face of propodeum distinctly rounded, about the same length as declivitous face; in lateral view, its highest part on the same plane to remainder of dorsum, dorsally dome-like. In lateral view, petiole triangular, inclined forward, with posterior face longer than anterior face; dorsum rounded.

Cuticle mostly dull to feebly shiny and finely microreticulate; reticulations more pronounced on head followed by mesosoma and gaster; propodeum relatively smooth and shiny; petiole smooth and shiny; pubescence absent on head, very sparse on mesosoma and relatively denser on gaster; scape with erect macrosetae and abundant pubescence (SMC = 30e40); pronotum and mesonotum with scattered, erect macrosetae of varying lengths (PMC = 2-4; MMC = 2-4).

Body color is blackish brown to black, antennae and legs brown; procoxae brown, mesocoxae and metacoxae yellowish brown; tarsi yellowish.

Queen
Wachkoo and Bharti (2015) - HL 0.95 mm; HW 0.90 mm; EL 0.30 mm; SL 1.07 mm; PrFL 0.98 mm; PrFW 0.25 mm; WL 1.54 mm. Indices: CI 94.74; SI 118.89; REL 31.39 (n = 1).

Generally, matches worker description, with modifications expected for caste and the following differences: head subtriangular with concave posterior margin; anterior clypeal margin nearly straight; petiole concave above; coloration pattern similar to adult workers; body covered with a more dense pubescence than in workers; overall microreticulate sculpture feebler than in workers (SMC 40 = 45; PMC = 6; MMC = 51).

Male
Wachkoo and Bharti (2015) - HL 0.59-0.67 mm; HW 0.48-0.58 mm; EL 0.23-0.25 mm; SL 0.77-0.85 mm; PrFL 0.67-0.74 mm; PrFW 0.15- 0.17 mm; and WL 0.87-0.95 mm. Indices: CI 81.48-89.28; SI 145.28-159.09; and REL 37.70-41.07 (n = 3).

Head oval; longer than wide; eyes large, subglobulose, slightly projecting beyond head outline in full-face view; three prominent ocelli present. Antennae filiform, scapes long, surpass posterior margin by about half their length. Mandibles slender with prominent, pointed apical and small preapical tooth, remainder of masticatory margin smooth, with indistinct, rounded basal angle that seamlessly blends into inner mandibular margin.

Mesosoma modified for the presence of a wing; in lateral view scutum and scutellum flat; propodeum indistinct, not higher than remainder of notum with very short dorsal face and long declivitous face; petiole as in worker.

Genitalia: Parameres triangular, turning slightly inward toward midline of body posteriorly; long setae extending off of parameres. Cuspi small, indistinct dorsally; digiti smooth, as long as parameres; strongly curved toward parameres. Penis valves projecting but not extending parameres.

Sculpture very much reduced than in worker caste; body mostly smooth and shiny at most with fine punctations; scutum microreticulate. Vestiture and color as in worker caste, but head sparsely pubescent (SMC 25 = 30; PMC = 0; MMC = 25-28).

References based on Global Ant Biodiversity Informatics

 * Chen Y. Q., Q. Li, Y. L. Chen, Z. X. Lu, X. Y. Zhou. 2011. Ant diversity and bio-indicators in land management of lac insect agroecosystem in Southwestern China. Biodivers. Conserv. 20: 3017-3038.
 * Chen Y., C. W. Luo, H. W. Li, Y. J. Liu, H. F. Zheng, and F. C. Yang. 2013. Investigation of ant species and distribution on Wuliang Mountain. Journal of Henan Agricultural Sciences 42(5): 118-122.
 * Chen Y., C.-W. Luo, H. W Li, Z. H. Xu, Y. J. Liu, and S. J. Zhao. 2011. The investigation of soil ant resources on the West slope of Mt Ailao. Hubei Agricultural Sciences 50(7): 1356-1359.
 * Fontanilla A. M., A. Nakamura, Z. Xu, M. Cao, R. L. Kitching, Y. Tang, and C. J. Burwell. 2019. Taxonomic and functional ant diversity along tropical, subtropical, and subalpine elevational transects in southwest China. Insects 10, 128; doi:10.3390/insects10050128
 * Li Q., Z. Lu, Z. Wei, M. Yanyan, and F. Ping. 2015. Communities of ground-dwelling ants in different plantation forest in arid-hot valleys of Jinsha river, Yunnan Province, China. Scientia Silvae Sinicae 51(8): 134-142.
 * Li Z.h. 2006. List of Chinese Insects. Volume 4. Sun Yat-sen University Press
 * Lu Z., Y. Chen, Q. Li, S. Wang, C. Liu, and W. Zhang. 2012. Effect of population of Kerria yunnanensis on diversity of ground dwelling ant. Acta Ecologica Sinica 32(19): 6195-6202.
 * Ran H., and S. Y. Zhou. 2012. Checklist of chinese ants: formicomorph subfamilies (Hymenoptera: Formicidae) II. Journal of Guangxi Normal University: Natural Science Edition 30(4): 81-91.
 * Song Y., Z. Xu, C. Li, N. Zhang, L. Zhang, H. Jiang, and F. Mo. 2013. An Analysis on the Ant Fauna of the Nangun river Nature Reserve in Yunnan, China. Forest Research 26(6): 773-780.
 * Wachkoo A. A., and H. Bharti. 2015. Taxonomic review of ant genus Nylanderia Emery, 1906 (Hymenoptera: Formicidae) in India. Journal of Asia-Pacific Entomology 8: 105-120.
 * Xu Z. 1998. A report of fourty-one ant species newly recorded in China from Xishuangbanna District of Yunnan Province (Hymenoptera: Formicidae). Zhongguo Xue Shu Qi Kan Wen Zhai 4: 1119-1121.