Polyrhachis euryala

Donisthorpe (1941) in his account of the synonymous rastellata var. baduri: "Miss L. E. Cheesman took a number of workers and three winged females in a carton nest under leaves of Pandanus." Nothing more is known about the biology of Polyrhachis euryala.

Identification
Polyrhachis euryala is distinctly more slender than Polyrhachis rastellata with the greatest width of the pronotal dorsum in the middle of its length. Polyrhachis rastellata is more robust, notably across the pronotum which is widest across, or just behind the shoulders. (Donisthorpe 1938)

Distribution
Patchily distributed through the eastern islands of Indonesia and across New Guinea.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia, Papua New Guinea.

Nomenclature

 *  euryala. Polyrhachis euryalus Smith, F. 1863: 16 (w.) INDONESIA (Misool I.). Combination in P. (Cyrtomyrma): Emery, 1925b: 208. Junior synonym of rastellata: Mayr, 1872: 138; Bingham, 1903: 414. Revived from synonymy as subspecies of rastellata: Emery, 1900d: 720; Emery, 1925b: 208. Revived status as species: Donisthorpe, 1938c: 259; Dorow, 1995: 22. Senior synonym of torricelliana: Viehmeyer, 1914b: 50; Kohout, 2009b: 44; of baduri: Kohout, 2009b: 44. See also: Kohout, 2006b: 125. Current subspecies: nominal plus javana.
 * torricelliana. Polyrhachis rastellata var. torricelliana Viehmeyer, 1912: 9, fig. 11 (w.) NEW GUINEA. Junior synonym of euryala: Viehmeyer, 1914b: 50.
 * baduri. Polyrhachis (Cyrtomyrma) rastellata var. baduri Donisthorpe, 1941h: 63 (w.q.) NEW GUINEA. Junior synonym of euryala: Kohout, 2009b: 45.

Polyrhachis euryalus

Holotype worker in. Labelled “M.” (= Misool I.) and with a Donisthorpe type-label.

Worker
Length 2 ½ lines. Black, smooth and shining; the thorax rounded above, not spined; the outline, when viewed laterally, semicircular; the legs obscure ferruginous. Abdomen globose; the node of the peduncle with four spines, the two inner ones shorter than the lateral pair, but all short and acute.

Queen
Colour and sculpture as in worker. The scale is broader and the punctures on thorax and petiole a little coarser. Wings yellowish, pterostigma and veins yellowish-brown. Long. 7·0-7·5 mill. (Donisthorpe 1941)

Type Material
Syntype workers and  – as reported by Kohout (2006).

Donisthorpe (1941) types of the synonymous rastellata var. baduri -

Type Locality Information
INDONESIA, Mysool Island, col. A.R. Wallace.

Donisthorpe (1941) types of the synonymous rastellata var. baduri: JAPEN ISLAND: Mt. Baduri, 1000 ft., viii.1938, col. L. E. Cheesman.

Additional References
Donisthorpe, H. 1938. The subgenus Cyrtomyrma Forel of Polyrhachis Smith, with descriptions of new species, etc. Annals and Magazine of Natural History (11)1: 246-267.

Donisthorpe, H. 1941h. The ants of Japen Island, Dutch New Guinea (Hym., Formicidae). Trans. R. Entomol. Soc. Lond. 91: 51-64.

Kohout, R. J. 2006. Review of Polyrhachis (Cyrtomyrma) Forel (Hymenoptera: Formicidae: Formicinae) of Australia, Borneo, New Guinea and the Solomon Islands with descriptions of new species. Memoirs of the Queensland Museum. 52:87-146.

Smith, F.1863. Catalogue of hymenopterous insects collected by Mr A.R. Wallace in the Islands of Mysol, Ceram, Waigiou, Bouru and Timor. Journal of the Proceedings of the Linnean Society, Zoology 7: 6-48.