Polyrhachis conspicua

Nothing is known about the biology of Polyrhachis conspicua.

Identification
Polyrhachis conspicua is a spectacular species and is similar to Polyrhachis inflata. Both share the exceptionally high, narrowly convex pronotum, which features a short, longitudinal furrow along its summit. However, they differ in size (HL 1.47-1.68 in Polyrhachis conspicua versus 1.68-1.81 in Polyrhachis inflata) and in general body sculpturation that is smooth and polished in Polyrhachis conspicua and closely reticulate-punctate and opaque in Polyrhachis inflata. (Kohout 2006)

Distribution
Polyrhachis conspicua occurs in Irian Jaya, Papua New Guinea and the adjacent Biak Island. (Kohout 2006)

This taxon was described from New Guinea.

Castes
Known only from workers.

Worker
Dimensions (holotype cited first): TL c. 6.00, 5.49-6.65; HL 1.59, 1.47-1.69; HW 1.53, 1.43-1.57; CI 96, 93-99; SL 1.90, 1.72-2.06; SI 124, 120-131; PW 1.15, 1.06-1.31; MTL 2.28, 1.93-2.34 (6 measured).

Clypeus in profile very weakly convex or almost straight in some specimens, narrowly rounding posteriorly into weakly medially impressed basal margin. Frontal triangle weakly impressed. Frontal carinae sinuate with very weakly raised margins; central area rather flat with frontal furrow weakly indicated for most of its length. Sides of head in front of eyes only weakly convex, almost straight, strongly converging towards mandibular bases; behind eyes sides rounding into convex occipital margin. Eyes moderately convex, clearly breaking lateral cephalic outline in full face view. Ocelli lacking, relative positions indicated by shallow punctures in sculpturation. Pronotum in dorsal view with humeri rounded. Mesosoma in profile with pronotum very strongly convex, very high, anterior face vertical; summit narrow with short, median, longitudinal furrow; promesonotal suture moderately impressed; mesonotal dorsum weakly convex; metanotal groove lacking, its position indicated by depression in mesosomal outline; propodeal dorsum descending in shallow curve into oblique declivity. Petiole with anterior face straight, posterior face convex; dorsum armed with four, acute, subequal spines; dorsal pair situated closer to each other than to lateral spines, tips slightly bent backwards. Subpetiolar process acute anteriorly, bluntly angular posteriorly. Anterior face of first gastral segment marginally lower than apices of dorsal petiolar spines.

Mandibles very finely, mostly longitudinally rugose. Head, mesosoma and gaster finely shagreened, rather polished; pronotal sculpturation becoming laterally reticulate; lower sides of mesosoma, notably meso- and metapleurae rather strongly reticulate-rugose. Petiole with anterior face finely reticulate, sculpturation more distinct on sides. Dorsal surfaces of head, mesosoma and gaster with piliferous pits and shallow punctures of various densities.

Mandibles with a few, rather short, semierect hairs near masticatory borders. Anterior clypeal margin with 1 or 2 relatively long, erect, anteriorly directed setae medially and several shorter setae laterally. A few paired, rather short, erect hairs near anterior and basal clypeal margins, several hairs along frontal carinae and pair of distinctly longer hairs on vertex. Summit of mesosoma with tuft of erect, somewhat curved hairs, more than half of greatest diameter of eyes in length (number of hairs in some specimens reduced to one or two probably due to abrasion). Posterior margins of gastral segments with a few, medium length, erect hairs, more abundant on ventral surfaces and around gastral apex. Very short, mostly appressed or decumbent hairs in various densities arising from pits and puctures over all body surfaces. Colour. Black with only mandibular masticatory borders, condylae, tips of apical funicular segments and joints between trochanters and femora, reddish brown. Tibiae towards their distal ends a shade lighter.

Queen
Unknown

Male
Unknown

Type Material
Holotype in, 1 paratype each in , , ,.

Type Locality Information
HOLOTYPE: INDONESIA, WEST IRIAN, Waris, S of Hollandia (= Sukarnaputra), 03°30’S, 140°55’E, 450-500m, 24-31.viii.1959, T.C. Maa (worker). PARATYPES: data as for holotype (1 worker); INDONESIA, WEST IRIAN, Nabire, S of Geelving Bay, 03°22’S, 135°29’E, 1-20m, 3.vii.1962, J.L. Gressitt & J. Sedlácek (worker); INDONESIA, Schouten Is, SE Biak I., 01°00’S, 136°00’E, 1.vii.1962, J.L. Gressitt & J. Sedlácek (2 workers). PAPUA NEW GUINEA, West Sepik Prov., Pes Mission, c.12km WSW of Aitape, 03°11’S, 142°15’E, <50m, 31.vii-3.viii.1984, RJK acc.84.160 (worker); Madang Prov., 40km W of Madang, 05°13’S, 145°25’E, 140m, 1.ii.1989, P.S. Ward #10113-24 (2 workers).