Polyrhachis capillata

Only two specimens of P. capillata are known, both collected at Kalgoorlie in the Goldfields region of Western Australia.

Identification
A member of the Polyrhachis gravis species-group. Kohout (2013) - Polyrhachis capillata is characterised by its relatively long hairs, notably on the front of the head, antennal scapes and legs, the distinct tuft of variously curved, medium length hairs on the posterior portion of propodeal dorsum around the propodeal teeth and the rather distinct, somewhat laminate humeral teeth.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Castes
Sexuals and immature stages unknown.

Nomenclature

 *  capillata. Polyrhachis (Campomyrma) capillata Kohout, 2013: 96, figs. 1C-D, G-H (w.) AUSTRALIA.

Worker
(holotype cited first) TL c. 9.68, 10.89; HL 2.28, 2.50; HW 1.96, 2.21; CI 86, 88; SL 2.56, 2.74; SI 131, 124; PW 1.87, 2.02; MTL 3.38, 3.83 (2 measured).

Mandibles with 6 teeth, distinctly reducing in length towards base. Anterior clypeal margin widely truncate medially, truncate portion bluntly and irregularly denticulate. Clypeus without distinct median carina; clypeus in profile very shallowly convex with raised anterior margin, virtually flat posteriorly. Frontal triangle only shallowly impressed. Frontal carinae sinuate with moderately raised margins; central area with flat frontal furrow. Sides of head in front of eyes converging towards mandibular bases in straight line; behind eyes sides converging into rather narrow occipital margin. Eyes convex, in full face view clearly breaking lateral cephalic outline. Ocelli lacking. Pronotal humeri produced into distinct, laminate, triangular teeth, lateral pronotal margins behind teeth converging posteriorly into promesonotal suture. Mesonotal dorsum with anterior corners rounded; lateral margins converging posteriorly towards flat mtamotal groove. Propodeal dorsum distinctly longer than wide with lateral margins converging posteriorly and terminating in short, upturned, divergent, acute teeth; dorsum curving into shallowly concave declivity in medially uninterrupted line. Petiole scale-like, virtually triangular in lateral view; dorsum armed medially with a pair of relatively short and slender, acute spines; inner margins of spines continuous medially, forming rather narrow, 'U' shaped dorsum of petiole; outer margins of spines steeply descending towards distinct, acute lateral spines that are only marginally shorter than dorsal pair. Gaster in lateral view with anterior face flat; anterior margin of first gastral tergite with blunt transverse carina.

Mandibles finely, longitudinally striate with numerous piliferous pits. Clypeus reticulate-punctate; head and dorsum of mesosoma reticulate-punctate with sculpture distinctly organised in mostly longitudinal striae, except on pronotal dorsum where striae are distinctly divergent towards lateral margins of segment; sides of mesosoma finely wrinkled. Anterior face of petiole rather coarsely reticulate-punctate with sculpture distinctly finer dorsally; posterior face more finely, transversely wrinkled. Gaster very finely reticulate, opaque.

Mandibles with numerous, curved, golden hairs at masticatory borders and along outer margins; truncate median portion of anterior clypeal margin with numerous, relatively long, golden setae; numerous shorter setae fringing margin laterally. All body surfaces, including appendages, with semierect to erect and variously curved, moderately long, golden hairs; hairs distinctly shorter and much diluted on pronotal and mesonotal dorsa; apical portion of propodeal dorsum with tuft of variously curved, medium length hairs. Hairs on head anteriorly inclined, those on dorsum of mesosoma, petiole and dorsum of gaster mostly erect, hairs on gastral venter distinctly posteriorly curved. Diluted, closely appressed, greyish pubescence present only on coxae, virtually absent from rest of body.

Mandibles distinctly reddish-brown towards masticatory borders, with bases and teeth dark reddish-brown; antennae virtually black with only apical funicular segments reddish-brown; Legs medium reddish-brown, with tibiae a shade darker; tarsi black. Venter and apex of gaster very dark, reddish-brown.

Etymology
Derived from the Latin capillus, meaning hair, in reference to the relatively long hair distributed over most body surfaces.

References based on Global Ant Biodiversity Informatics

 * Kohout R.J. 2013. A Review of the Polyrhachis gravis and micans species-groups of the subgenus Campomyrma Wheeler (Hymenoptera: Formicidae: Formicinae). Memoirs of the QLD Museum-Nature 56: 92-117