Polyrhachis manni

Specimens have been collected from 230-840 m, with one worker found in a malaise trap.

Identification
A member of the Polyrhachis mucronata  species group.

Kohout (2008a) - Polyrhachis manni is undoubtedly closely related to Polyrhachis lucidula and to Polyrhachis ridleyi. In addition to their similar general appearance, they all have rather broad petiolar spines. However, the spines in P. manni are distinctly less massive than in the other two species and the dorsum of the petiole bears two short, acute, intercalary spines that are lacking in both P. lucidula and P. ridleyi.

Distribution based on Regional Taxon Lists
Indo-Australian Region: Indonesia, Philippines, Sulawesi.

Castes
Known only from the worker caste.

Nomenclature

 *  manni. Polyrhachis manni Kohout, 2008a: 304, figs. 10G-H (w.q.) INDONESIA (Sulawesi).

Worker
(holotype cited first): TL c. 5.19, 5.04-5.49; HL 1.40, 1.33-1.40; HW 1.20, 1.12-1.20; CI 86, 84-86; SL 1.65, 1.56-1.65; SI 137, 137-145; PW 0.94, 0.87-1.00; MTL 1.68, 1.65-1.78 (6 measured).

Anterior clypeal margin with rather shallow, medially notched, rectangular flange, flanked by acute denticles. Clypeus with blunt median carina that is indistinct anteriorly; clypeus in profile convex, posteriorly rounding into weakly impressed basal margin, laterally basal margin indicated by thin, sculpture-breaking line. Frontal triangle shallowly impressed. Frontal carinae sinuate with raised margins; central area with weakly impressed frontal furrow. Sides of head in front of eyes convex, rounding into mandibular bases; behind eyes sides rounding into convex occipital margin. Eyes convex, in full face view breaking lateral cephalic outline. Ocelli lacking. Pronotal humeri armed with small, distinct teeth; lateral pronotal margins shallowly emarginate behind spines and rounded posteriorly. Promesonotal suture distinct; mesonotum rather strongly narrowed posteriorly; metanotal groove a distinct line, posteriorly bowed and weakly raised medially. Propodeal dorsum extremely short, with lateral margins forming outer edges of divergent, horizontal spines with their tips weakly bent downwards; declivity relatively high, very steep. Petiole with anterior face straight, posterior face convex; dorsum armed with a pair of horizontal curved spines that conform to the shape of gastral base in dorsal view and a pair of very short, acute, dorsoposteriorly directed, intercalary teeth. Anterior face of first gastral segment with flat base and anterodorsal margin widely rounding onto dorsum.

Mandibles finely longitudinally striate with numerous piliferous pits. Head, mesosoma and petiole reticulate-punctate with sculpturation on meso-and metapleurae somewhat wrinkled. Gaster finely shagreened.

Mandibular masticatory borders and outer margins with numerous, relatively long, curved, golden hairs. Anterior clypeal margin with a few longer, anteriorly directed setae medially and several shorter setae fringing margin laterally. Two pairs of relatively short, erect hairs arising near anterior clypeal margin, one pair near basal margin and a few very short hairs fringing apex of antennal scapes. Posterior faces of fore coxae with several medium length, downward-directed hairs. Subpetiolar process anteriorly with tuft of short hairs. Gaster with only a few erect hairs lining apical segments dorsally; distinctly longer, more abundant hairs lining segments on venter. Extremely short, appressed, very diluted pubescence over most dorsal surfaces; pubescence on gastral dorsum more abundant, but not so dense as to hide underlying sculpturation.

Colour. Black; mandibles, antennal scapes, fore coxae and tibiae medium reddish-brown with femora very dark reddish-brown. Small patch on mandibular masticatory borders, condylae, apical funicular segments, coxae of middle and hind legs and all trochanters very light yellowish-brown, with coxae blotched reddish-brown. Apical gastral segments, notably on ventral aspect, diffusely reddish-brown.

Queen
TL c. 7.21; HL 1.62; HW 1.34; CI 83; SL 1.87; SI 139; PW 1.53; MTL 2.09 (1 measured).

Very similar to worker but larger and with usual differences indicating caste, including three ocelli and complete thoracic structure. Pronotal humeri armed with distinct teeth; mesoscutum almost as long as wide, with anterior face and dorsum forming a continuous, weakly convex line in lateral view; mesoscutellum convex. Propodeal dorsum short, descending into oblique declivity in medially uninterrupted line; spines broad-based, about twice as long as their basal widths. Petiole similar to that in worker with spines distinctly shorter. Sculpturation of body, pilosity and colour virtually as in worker.

Type Material
HOLOTYPE: SULAWESI SELATAN: Karaentha, 05°0.2S, 119°44’E, 270m, K. Ogata & K. Masaoka #99 (worker). PARATYPES: data as for holotype (worker); SE of Laduladu, 02°33’S, 121°22’E, 230m, 21.x.1999, K. Ogata & K. Masaoka #95 (worker); Bantimoerong (= Bantimurung), 1937, W. M. Mann, NGS SI Exp. (3 workers). SULAWESI UTARA: Dumoga-Bone NP, Rentice II, 280m, 1-24.xi.1985, malaise trap (Bosmans & Van Stalle #106) (worker). Holotype (QMT144152) and 1 paratype in ; 1 paratype each in, , , and.

References based on Global Ant Biodiversity Informatics

 * Kohout, R. J. 2008. A review of the Polyrhachis ants of Sulawesi with keys and descriptions of new species (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum 52:255-317.
 * Robson Simon Ant Collection, 05-Sept-2014