Polyrhachis brachyspina

Nothing is known about the biology of .

Identification
A member of the Polyrhachis relucens species group in the subgenus Myrma

Kohout (2008) - Polyrhachis brachyspina is characterised by a rather short mesosoma with broadly-based pronotal spines and very short petiolar spines.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia, Sulawesi.

Nomenclature

 *  brachyspina. Polyrhachis brachyspina Kohout, 2008a: 268, figs. 2C-D (w.) INDONESIA (Sulawesi).

Worker
TL c. 7.76; HL 1.96; HW 1.62; CI 83; SL 2.25; SI 139; PW 1.22; MTL 2.50.

Anterior clypeal margin arcuate, entire. Clypeus with blunt longitudinal median carina; in profile shallowly concave, with distinctly raised anterior margin and flat basal margin. Frontal triangle distinct. Frontal carinae sinuate, margins weakly raised; central area flat, relatively wide with weakly impressed frontal furrow. Sides of head in front of eyes straight, weakly converging towards mandibular bases; behind eyes sides rounding into broadly convex occipital margin. Eyes moderately convex, in full face view breaking lateral cephalic outline. Ocelli lacking. Pronotal dorsum convex in outline with pair of broad-based, anterolaterally and weakly downwards directed, acute spines; lateral edges of spines continuous with weakly posteriorly converging pronotal margins. Mesonotum wider than long. Propodeum with lateral margins parallel, terminating posteriorly in distinct, upturned denticles; posterior margins meeting medially to form a distinct transverse ridge that separates propodeal dorsum from distinctly concave declivity. Petiole biconvex in profile; armed with a pair of short, acute, dorsolaterally directed, posteriorly curved spines on dorsolateral angles; spines separated by relatively wide, weakly medially convex, dorsal margin; short, acute tooth situated laterally gastral segment concave with rather distinct anterodorsal margin narrowly rounding onto dorsum of segment.

Mandibles longitudinally striate. Clypeus shagreened, sides of head rather reticulate-rugose; vertex and area between frontal carinae and eyes with irregular, mostly longitudinal striae. Central area rugose with distinct punctures; shagreened along occipital margin. Pronotal dorsum shagreened with faint longitudinal striations. Dorsa of mesonotum and propodeum somewhat irregularly, mostly longitudinally, striate-punctate; sides of mesosoma reticulate-punctate. Petiole shagreened dorsally with sculpturation coarser at base. Gaster very finely shagreened.

Mandiblar masticatory borders with several yellow, curved hairs. Anterior clypeal margin with a few, anteriorly directed longer setae and several shorter setae fringing margin laterally. A few pairs of erect, medium length hairs near anterior and basal clypeal margins. Gaster with several, erect, longer hairs, arising along posterior margins of apical segments and around apex. Relatively long, appressed, yellow or golden pubescence in various densities over most dorsal body surfaces, but virtually absent from central area, vertex, sides of head and between frontal carinae and eyes. Pubescence on gaster distinctly shorter, more appressed and dense, almost completely hiding underlying sculpture.

Colour. Black throughout; only tips of mandibular teeth, extreme tips of apical funicular segments and tarsal claws, light reddish-yellow.

Type Material
HOLOTYPE, SULAWESI UTARA: Dumoga-Bone NP, 11.ii.1985, N.E. Stork et al. (worker). Unique holotype in.

References based on Global Ant Biodiversity Informatics

 * Kohout, R. J. 2008. A review of the Polyrhachis ants of Sulawesi with keys and descriptions of new species (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum 52:255-317.