Polyrhachis (Aulacomyrma) sulcifera, Kohout, R. J., 2007

Kohout, R. J., 2007, Revision of the subgenus Aulacomyrma Emery of the genus Polyrhachis F. Smith, with descriptions of new species., Advances in ant systematics (Hymenoptera: Formicidae): Homage to E. O. Wilson - 50 years of contributions. (Memoirs of the American Entomological Institute 80), pp. 186-253 : 210-211

Polyrhachis (Aulacomyrma) sulcifera , new species

Figures 37, 40, 43

TYPE MATERIAL

HOLOTYPE: PAPUA NEW GUINEA, Wum, Upper Jimmi Valley , 05 º 25 ’ S, 144 º 23 ’ E, 840 m, 17. vii. 1955, J. L. Gressitt (worker). Type distribution: unique holotype in MCZC .

WORKER

Dimensions of holotype: TL c. 5.19; HL 1.28; HW 1.12; CI 87; SL 1.40; SI 125; PW 1.06; MTL 1.28.

Anterior clypeal margin arcuate, entire; in profile clypeus very weakly convex with rather shallow basal margin indicated by hairline break in cephalic sculpture. Sides of head in front of eyes only weakly convex. Eyes strongly convex, in full face view clearly breaking cephalic outline. Mesosomal dorsum laterally marginate along entire length. Pronotal humeri armed with strong, broad-based, acute teeth, with distinctly raised margins. Promesonotal suture distinct; metanotal groove lacking, position indicated laterally by shallow emargination in the mesosomal margin. Propodeal dorsum with laterally widened margin, forming distinct rounded prominences, posteriorly continued as transverse, inwardly bowed ridges that almost completely separate dorsum from declivity, except for very narrow medial gap. Petiole distinctly transverse, with acute, medially jagged dorsal margin and slender, acute, strongly upturned lateral spines. Anterior face of first gastral segment concave with anterodorsal margin acute, but not distinctly raised above dorsal face of segment.

Mandibles finely longitudinally striate. Sculpture of head and body consisting of widely spaced, mostly regular, longitudinal striae, giving dorsal surfaces a “ ploughed ” appearance. Sides of mesosoma with mostly oblique striae, propodeal declivity rather smooth. Petiole shagreened. Gaster with fine, mostly longitudinal striation, striae on dorsum converging towards anterodorsal margin.

Rather short, mostly erect, silvery and yellowish hairs present on all body surfaces, except inferior edges of antennal scapes, dorsal petiolar margin and extensor surfaces of femora and tibiae. Hairs on gastral dorsum more golden and posteriorly curved, those on apex distinctly longer. Appressed pubescence generally very sparse or absent, somewhat more abundant and yellowish on pronotal and propodeal dorsa, notably on humeral teeth and along posterior propodeal margin, silvery on metapleuron and lateral borders of propodeal declivity. Gastral pubescence more abundant and distinctly golden.

Black, with striae and interspaces rather shiny. Antennal scapes, joints of femora and tibiae and proximal portion of basal tarsal segments black or very dark brown. Funiculi and rest of legs light or medium yellow.

Sexuals and immature stages unknown.

ETYMOLOGY

Derived from the Latin word sulcus, meaning furrow or goove in reference to the “ ploughed ” appearance of the dorsal sculpture.

REMARKS

A remarkable species easily recognized by its cephalic and mesosomal striation, that has only about 13 widely spaced striae present across the pronotal dorsum.