Polyrhachis sulawesiensis

Specimens have been collected from fogging samples.

Identification
A member of the Polyrhachis flavicornis species group.

Kohout (2008) - Polyrhachis sulawesiensis is a very distinct species of Myrmatopa that superficially resembles some species of the subgenus Campomyrma. It also resembles Polyrhachis neglecta, described above, but differs in several characters. The head and body sculpturation in P. sulawesiensis is reticulate-rugose and distinctly coarser than the reticulate-punctate sculpturation in P. neglecta. The pronotal and propodeal dorsa in P. sulawesiensis are distinctly wider than dorsum of the mesonotum. In contrast, the pronotal, mesonotal and propodeal dorsa in P. neglecta become progressively narrower posteriorly. The lateral petiolar spines in P. sulawesiensis are distinctly divergent and dorsum of petiole bears a pair of acute intercalary spines. The lateral petiolar spines in P. neglecta are longer, more strongly posteriorly directed and are almost parallel at their tips, and the dorsal petiolar margin has a pair of rather indistinct tuberculae.

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

Castes
Known only from the worker caste.

Nomenclature

 *  sulawesiensis. Polyrhachis sulawesienis Kohout, 2008a: 271, figs. 7G-H (w.) INDONESIA (Sulawesi).

Worker
(holotype cited first): TL c. 7.36, 6.95-7.76; HL 1.87, 1.87-1.90; HW 1.56, 1.53-1.56; CI 83, 81-82; SL 1.78, 1.75-1.84; SI 114, 114-118; PW 1.28, 1.29-1.37; MTL 1.93, 1.93-2.06 (4 measured).

Anterior clypeal margin with shallow, medially notched flange, laterally flanked by distinct, blunt denticles. Clypeus with poorly defined, blunt, median carina; clypeus straight in profile with weakly impressed anterior margin, posteriorly rounding into shallow basal margin, laterally indicated by a thin line breaking sculpturation. Frontal triangle distinct. Frontal carinae sinuate with margins only weakly raised; central area shallow with weakly impressed frontal furrow. Sides of head in front of eyes straight, converging towards mandibular bases; behind eyes sides rounding into convex, medially narrowly emarginated, occipital margin. Eyes convex, in full face view distinctly exceeding lateral cephalic outline; more convex laterally than medially, notably when viewed from behind. Ocelli lacking. Mesosoma with pronotal and propodeal dorsa distinctly wider than dorsum of mesonotum. Pronotal humeri angular with lateral margins weakly and narrowly emarginate behind angles, rounded posteriorly; greatest width of pronotal dorsum at or just behind mid-length of segment. Propodeum distinctly transverse, wider than long; anterior propodeum distinctly wider than posterior width of mesonotum; lateral propodeal margins terminating posteriorly in short, upturned teeth; posterior margins of teeth continued inwards and somewhat downwards for a short distance but not meeting; propodeal dorsum descending into vertical declivity in medially uninterrupted line. Petiole armed with a pair of dorsolaterally directed, divergent lateral spines and a pair of very distinct, acute, intercalary spines arising from dorsal margin medially. Anterior face of first gastral segment rather flat, only marginally higher than height of petiole, with anterodorsal margin widely rounding onto dorsum.

Mandibles very finely reticulate with numerous piliferous pits. Head, mesosoma and petiole rather coarsely reticulate-rugose; gaster finely reticulate-punctate. Sculpturation somewhat longitudinally directed on pronotal dorsum, distinctly irregular elsewhere. Antennal scapes and legs reticulate-punctate.

Mandibular masticatory borders with several curved, golden hairs. Anterior clypeal margin fringed with several rather short, anteriorly directed setae. Two pairs of very short, erect hairs along frontal carinae and single pair of anteriorly directed, very short hairs on vertex. A few very short, erect hairs fringing apices of antennal scapes and a few slightly longer hairs arising from anterior faces of fore coxae. Several distinctly longer, erect hairs on ventral surface of gaster and fringing gastral apex.

Colour. Black, with appendages and gaster very dark reddish-brown. Mandibular teeth, condylae, extreme tip of apical funicular segments and trochanters mostly reddish-brown.

Type Material
HOLOTYPE: SULAWESI UTARA: Dumoga-Bone NP, 400m, 11.ii.1985, fog., N.E. Stork et al. (worker). PARATYPES: data as for holotype (worker); ditto, 230m, 11.vii.1985, fog., N.E. Stork et al. (worker); ditto, 7.vi.1985, N.E. Stork et al. (worker). Holotype and paratype in ; 1 paratype each in and.

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.