Polyrhachis shixingensis

Identification
A member of the xiphias species-group.

Kohout (2013) - Polyrhachis shixingensis is rather similar to Polyrhachis hashimotoi and Polyrhachis xiphias, with differences between all three species discussed in remarks section under P. hashimotoi.

Wu & Wang (1995) - This species resembles Polyrhachis clypeatus but can be easily distinguished from it by the following characters: the petiolar scale with only two long spines, the mesonotum longer than broad, and the posterolateral angles of the propodeum armed with two stout spines which project rearward.

Distribution
The report of this species from Thailand by Khachonpisitsak et al. (2020) is a misidentification of Polyrhachis lao (Jaitrong et al., 2023).

Distribution based on Regional Taxon Lists
Palaearctic Region: China.

Castes
Males are present in the collection of KFBG but have not been described.

Nomenclature

 *  shixingensis. Polyrhachis shixingensis Wu & Wang, 1995: 166, figs. 334, 348, 351 (w.) CHINA. Kohout, 2013: 23, figs. 10, 12, 13 (q.).

Description
Kohout (2013):

Worker
Dimensions: TL c. 6.45-7.16; HL 1.56-1.81; HW 1.47-1.62; CI 88-93; SL 1.59-1.76; SI 108-112; PW 0.87-1.03; MTL 1.72-1.93 (6 measured).

Queen
Dimensions: TL c. 9.47; HL 2.25; HW 1.87; CI 83; SL 1.87; SI 100; PW 1.50; MTL 2.18 (1 measured)

Queen very similar to worker with usual characters of full sexuality, including three ocelli, complete thoracic structure and wings. Eyes larger than in worker, in full-face view marginally exceeding lateral cephalic outline. Pronotal humeri bluntly angular with anterior margins weakly indicated for short distance towards pronotal collar. Mesoscutum in lateral view with relatively low, widely rounded anterior margin and posteriorly flat dorsum; median line indistinct; parapsides flat. Mesoscutellum weakly convex, only marginally elevated above dorsal plane of mesosoma, Propodeal dorsum weakly transversely convex with lateral margins converging posteriorly and terminating in somewhat dorsolaterally flattened, broadly based, propodeal spines. Petiole identical to worker with marginally shorter spines.

Sculpturation of head similar to worker, finely reticulate-punctate; mesoscutum irregularly, rather coarsely rugose, sculpture somewhat longitudinally directed posteriorly; propodeal dorsum, including spines, finely reticulate-punctate. Gaster shagreened, rather highly polished.

Anterior clypeal margin with several longer, golden setae medially and numerous shorter setae fringing margin laterally. Head, including clypeus, with numerous golden, anteriorly inclined, paired hairs. Mesoscutum with only two pairs of semierect, medium length hairs. Gaster, except dorsum of first tergite, with numerous posteriorly inclined, relatively long, golden hairs along posterior margins of segments and around apex. Very short, appressed, silvery or pale golden pubescence only very sparingly distributed over most body surfaces.

Colour virtually identical to that in worker.

References based on Global Ant Biodiversity Informatics

 * Guénard B., and R. R. Dunn. 2012. A checklist of the ants of China. Zootaxa 3558: 1-77.
 * Kohout R. J. 2013. A review of the Polyrhachis xiphias species-group of the subgenus Campomyrma Wheeler (Hymenoptera: Formicidae: Formicinae). Asian Myrmecology 5: 21-27.
 * Ran H., and S. Y. Zhou. 2013. Checklist of Chinese Ants: Formicomorph Subfamilies ( Hymenoptera: Formicidae) (III). Journal of Guangxi Normal University : Natural Science Edition 31(1): 104-111.
 * Robson Simon Database Polyrhachis -05 Sept 2014
 * Staab M., A. Schuldt, T. Assmann, H. Bruelheide, and A.M. Klein. 2014. Ant community structure during forest succession in a subtropical forest in South-East China. Acta Oecologia 61: 32-40.
 * Zhou S.-Y. 2001. Ants of Guangxi. Guangxi Normal University Press, Guilin, China, Guilin, China. 255 pp.