Polyrhachis browni

The type material was collected from a fogging sample.

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

Kohout (2008) - Polyrhachis browni is rather similar to Polyrhachis brendelli with distinguishing characters listed under the latter.

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

Nomenclature

 *  browni. Polyrhachis browni Kohout, 2008a: 270, figs. 2G-H (w.) INDONESIA (Sulawesi).

Worker
(holotype cited first): TL c. 9.42, 8.87-9.47; HL 2.40, 2.28-2.43; HW 1.75, 1.67-1.76; CI 73, 71-74; SL 2.99, 2.93-3.06; SI 171, 172-178; PW 1.40, 1.26-1.41; MTL 3.58, 3.43-3.73 (9 measured).

Anterior clypeal margin arcuate, entire. Clypeus with blunt, longitudinal carina medially; sinuate in profile with elevated anterior margin; basal clypeal margin weakly impressed, laterally indicated by a thin line breaking sculpturation. Frontal triangle distinct. Frontal carinae sinuate with laminate margins that are elevated anteriorly and posteriorly flat; central area concave anteriorly, with distinct frontal furrow. Sides of head in front of eyes straight, weakly converging towards mandibular bases; behind eyes sides weakly convex and rounding into occipital margin. Eyes convex, situated well forward from occipital corners; in full face view breaking lateral cephalic outline. Ocelli lacking, relative positions indicated by small pits in sculpturation. Pronotal dorsum with long, slender, acute spines that are directed anterolaterally and curve more anteriorly and slightly downwards at mid length. Lateral edges of spines continuous with parallel margins of pronotum. Mesonotum transverse, with raised anterior corners; lateral margins shallowly emarginate medially and rounded posteriorly. Propodeal dorsum with margins distinctly converging posteriorly and terminating in upturned, tooth-like denticles, their posterior margins meeting medially, forming an inward-bowed ridge that separates propodeal dorsum from declivity. Petiole biconvex in profile; armed with a pair of widely separated, dorsolaterally and weakly posteriorly directed, acute spines; dorsal margin between spines weakly concave, more-or-less acute; lateral margin of petiole below base of each spine with a secondary, short, acute tooth. Anterior face of first gastral segment weakly concave with anterodorsal margin narrowly rounding onto dorsum.

Mandibles finely, mostly longitudinally striate, somewhat polished, with numerous piliferous pits towards bases. Head, mesosoma, including declivity, petiole and gaster reticulate-punctate with sculpturation very fine and rather uniformly distributed over all body surfaces, except pronotal and petiolar spines that are rather smooth and polished.

Mandibular masticatory borders with several curved, golden hairs. Anterior clypeal margin with medium length, anteriorly directed, golden setae and with a few short setae fringing margin laterally. Mostly paired, medium length, erect, yellow and golden hairs near anterior and basal clypeal margins, along frontal carinae and a single pair of hairs on vertex. Gaster with only a few, relatively long, erect hairs at apex and posterior margins of apical segments on venter.

Colour. Black throughout; only extreme tip of apical funicular segments and tarsal claws light reddish-brown.

Type Material
HOLOTYPE: SULAWESI UTARA: Dumoga-Bone NP, 2.xii.1985, fog., N.E. Stork et al. (worker). PARATYPES: data as for holotype (worker); ditto, 11.vii.1985, fog., N.E. Stork et al. (2 workers) ditto, 25.ii.1985, N.E. Stork et al. (4 workers); ditto, 230m, 10.ii.1985, fog., N.E. Stork et al. (worker); Holotype and 2 paratypes in, 1 paratype each 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.