Polyrhachis seducta

Polyrhachis seducta is known only from Barrow Island. All specimens were collected foraging on the ground and it is highly probable that the species is a terrestrial nester like most other Hagiomyrma species.

Identification
A member of the penelope species-group in the Polyrhachis subgenus Hagiomyrma. Kohout (2013) - Polyrhachis seducta is somewhat similar to Polyrhachis melanura. However, P. seducta can be distinguished by the distinctly deeper body sculpturation, more strongly posteriorly converging promesonotal lateral margins and short, bristle-like hairs on antennal scapes. Polyrhachis seducta is also very similar to Polyrhachis tanami, with both having numerous short hairs on the antennal scapes and a distinctly swollen posterior face of the petiole. They differ mainly by the hairs on dorsum of mesosoma that are erect and very short in P. seducta, while they are longer and distinctly posteriorly directed in P. tanami.

Distribution based on Regional Taxon Lists
Australasian Region: Australia.

Castes
Known only from the worker caste.

Nomenclature

 *  seducta. Polyrhachis (Hagiomyrma) seducta Kohout, 2013: 545, figs. 8G-H (w.) AUSTRALIA.

Worker
(holotype cited first) TL c. 6.85, 5.64-7.31; HL 1.75, 1.47- 1.75; HW 1.40, 1.18-1.40; CI 80, 80-83; SL 2.06, 1.68-2.06; SI 147, 140-150; PW 1.28, 1.09-1.28; MW 0.82, 0.65-0.84; PMI 156, 156-174; MTL 2.21, 1.72-2.28 (6 measured).

Anterior clypeal margin with denticulate, median flange. Clypeus with median carina, weakly sinuate in profile, posteriorly rounding into moderately impressed basal margin. Frontal triangle indistinct. Frontal carinae sinuate with weakly raised margins; central area flat with distinct frontal furrow. Sides of head in front of eyes converging in virtually straight line towards mandibular bases; behind eyes, sides rounding into convex occipital margin. Eyes moderately convex, in full face view marginally exceeding lateral cephalic outline. Ocelli lacking. Pronotal humeri rounded with anterior margins weakly raised; pronotal dorsum widest at midlength, lateral margins converging into distinctly impressed promesonotal suture. Mesonotal dorsum with lateral margins converging towards indistinct metanotal groove. Propodeal dorsum armed with moderately long, weakly divergent spines. Petiole with posterior face distinctly swollen; dorsum armed with pair of slender, divergent spines with tips weakly curved upwards. Anterior face of first gastral tergite widely rounding onto dorsum.

Mandibles finely longitudinaly striate with piliferious pits. Clypeus closely punctate. Head reticulate-punctate, sculpturation on vertex distinctly coaser and more-or-less regularly, longitudinally striate. Dorsum of mesosoma reticulate-punctate; sculpturation on mesonotum organised into rather uneven, longitudinal striae, curved obliquely towards lateral margins on propodeal dorsum. Sides of mesosoma, declivity and petiole reticulate-punctate. Spines sculptured at bases, smooth and polished towards tips. Gaster closely shagreened, opaque.

Mandibles with numerous, relatively short, curved hairs at masticatory and outer borders. Anterior clypeal margin medially with a few, anteriorly directed setae. Dorsa of head, mesosoma and petiole with numerous, short, bristle-like, golden hairs, many fringing lateral and dorsal outline of head; appendages, including antennal scapes, with very short, erect hairs. Gaster with abundant, posteriorly inclined, marginally longer, golden hairs, distinctly longer around apex and on venter. Very sporadic, short, appressed, silvery pubescence in various densities over most body surfaces; pubescence golden and denser on dorsum of gaster but not hiding underlying sculpturation.

Black; mandibular masticatory borders and appendages dark to very dark reddish-brown.

Etymology
Derived from the Latin seductus, meaning remote, distant, in reference to the species rather isolated occurrence on Barrow Island.

References based on Global Ant Biodiversity Informatics

 * Kohout R.J. 2013. Revision of Polyrhachis (Hagiomyrma) Wheeler, 1911 (Insecta: Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum  Nature 56: 487577