Polyrhachis (Aulacomyrma) porcata Emery, 1921

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: 234-235

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Polyrhachis (Aulacomyrma) porcata Emery, 1921


Polyrhachis (Aulacomyrma) porcata Emery, 1921   HNS  

Figures 92, 95, 98

Polyrhachis (Aulacomyrma) porcata Emery, 1921: 20   HNS   . Holotype worker. Type locality: NEW GUINEA (NE), (Staudinger et Bang-Hass), MCSN (examined).   Polyrhachis (Aulacomyrma) porcata Emery, 1925: 198   HNS   , Pl. 3, figs 29, 29 a.


Dimensions (holotype cited first): TL c. 5.74, 6.35; HL 1.47, 1.68; HW 1.28, 1.47; CI 87, 87; SL 1.56, 1.75; SI 122, 119; PW 1.06, 1.18; MTL 1.62, 1.75 (2 measured).

Anterior clypeal margin arcuate, with very narrow medial notch; clypeus weakly convex in profile with basal margin slightly impressed medially and marked laterally by a hairline break in cephalic sculpture. Frontal triangle indistinct; frontal carinae strongly sinuate with laminate lobes. Eyes only weakly convex, not breaking cephalic outline in full face view. Sides of head weakly converging anteriorly; rounding behind eyes into convex preoccipital margin. Pronotal dorsum immarginate; humeri armed with short, laterally and anteriorly directed, rather acute spines, margins raised with dorsal surface between them weakly concave. Promesosonal suture strongly impressed; metanotal groove lacking. Mesonotal and propodeal dorsa with outermost striae stronger than others, forming ill-defined and incomplete lateral margins. Propodeal dorsum posteriorly immarginate, unarmed, descending into declivity in sudden, unbroken curve. Petiole with dorsal margin acute, entire, somewhat medially and dorsally compressed and sinuate in dorsal view; lateral teeth rather short, curved posteriorly. Anterior face of first gastral segment concave medially, dorsal margin of concavity produced dorso-medially into prominent ridge, distinctly raised above dorsal surface of segment.

Mandibles finely, longitudinally striate. Head mostly longitudinally striate with striae on vertex converging medially between frontal carinae. Pronotal dorsum with outermost striae almost semicircular and continuing uninterrupted in oblique direction on sides; innermost striae more narrow and inverse U-shaped. Striae on mesonotal and propodeal dorsa converging posteriorly, terminating just short of declivity. Anterior and posterior faces of petiole transversely striate, striae somewhat bowed dorsally. (These are well marked laterally, but somewhat obscure medially in specimen from Gemeheng.) Dorsum of first gastral segment finely, longitudinally striate, central striae converging anteriorly and terminating before reaching almost smooth, finely shagreened, dorso-medial prominence.

Medium length, yellowish or golden hairs present on all body surfaces; erect or semierect on dorsum and sides of head in front of eyes, between frontal carinae and on vertex. Antennal scape with numerous short erect hairs along leading edge. Numerous erect, suberect and variously curved hairs on dorsum of mesosoma, but virtually absent from sides. Petiole with pair of short erect hairs arising on each side along dorsal margin. Gaster with numerous, relatively long hairs along posterior margins of segments; hairs on dorsum of first gastral segment shorter and distinctly curved posteriorly. Appressed pubescence virtually absent, with only small, silvery patches on metapleuron, lateral and dorsal borders of propodeal declivity, sides of petiole and coxae. Pubescence on dorsum of gaster confined to narrow, silvery band along posterior edge of first gastral segment; anterior portion of dorsal face, with rather diluted golden pubescence.

Black. Appendages very dark reddish-brown, with only tip of apical funicular segment and apical tarsal segments very light reddish-brown.

Sexuals and immature stages unknown.


NEW GUINEA: Huon Penins., Mongi Watershed, Gemeheng, 1300 m, 11 - 13. iv. 1955 (E. O. Wilson # 788) (w).


A very distinct, virtually black species that is more-or-less regularly longitudinally striate with the petiole transversely striate. Pubescence is virtually lacking from the body, with only a few scattered, erect, hairs on the head, dorsum of mesonotum, propodeum and the gaster.


Italy, Genova, Museo Civico di Storia Naturale