Polyrhachis ugiensis

Nothing is known about the biology of Polyrhachis ugiensis.

Identification
Polyrhachis ugiensis is most similar to Polyrhachis fulakora. In outline, the pronotal dorsum of Polyrhachis ugiensis is much more convex, especially anteriorly, where it rises from the pronotal collar almost vertically for a short distance and then continues in a convex outline to the promesonotal suture. In contrast, the pronotal dorsum in Polyrhachis fulakora is only weakly convex from the pronotal collar to the promesonotal suture. Also, the lateral petiolar spines in Polyrhachis ugiensis are greatly reduced, while the petiolar spines in Polyrhachis fulakora are more-or-less subequal. Both species differ from the closely allied Polyrhachis johnsoni in having the greatest width of the pronotal dorsum at, or about, the middle of its length. In Polyrhachis johnsoni the greatest width of the pronotal dorsum is across, or just below the humeri. (Kohout 2006)

Distribution
Solomon Islands.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Solomon Islands.

Nomenclature

 *  ugiensis. Polyrhachis (Cyrtomyrma) rastellata subsp. ugiensis Mann, 1919: 389 (w.) SOLOMON IS. Raised to species: Donisthorpe, 1938c: 260. See also: Kohout, 2006b: 142.

Worker
Length 5.5-6 mm.

The specimens from the eastern Solomons represent still another form of this variable species, characterized by the shorter spines of the petiole, which in some specimens have the lateral ones reduced to mere angles, and in the color of the legs. The femora and the tibiae are reddish brown, with the bases of the latter and the tarsi black. The antennae are black, except the extreme tip of the last segment, which is brown.

Type Material
Syntype workers:, , and  - as reported by Kohout (2006).

Type Locality Information
The material the description was based on was stated by Mann to have been collected from: SOLOMON IS, Ugi, Pawa; San Cristoval, Wai-ai, Pamua, Wainoni Bay; Three Sisters, Malapaina.

Additional References
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.

Mann, W.M. 1919. The ants of the British Solomon Islands. Bulletin of the Museum of Comparative Zoology at Harvard College 63: 273-391