Polyrhachis sedlaceki

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Polyrhachis sedlaceki
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hymenoptera
Family: Formicidae
Subfamily: Formicinae
Tribe: Camponotini
Genus: Polyrhachis
Subgenus: Cyrtomyrma
Species: P. sedlaceki
Binomial name
Polyrhachis sedlaceki
Kohout, 2006

Fig. 11B Kohout 2006 sedlaceki.png

Nothing is known about the biology of Polyrhachis sedlaceki.


Polyrhachis sedlaceki is easily distinguished from all other New Guinean Cyrtomyrma by its highly polished appearance and complete lack of dorsal pilosity. It also differs in the unique shape of the petiole that is armed with two long, posterolaterally directed spines. All other known New Guinean species feature a normal scale-like petiole. (Kohout 2006)

Keys including this Species


Known only from the type locality - PAPUA NEW GUINEA, Morobe Prov.,

Distribution based on Regional Taxon Lists

Indo-Australian Region: New Guinea (type locality).

Distribution based on AntMaps


Distribution based on AntWeb specimens

Check data from AntWeb


Known only from the type material.



Known only from workers.


The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.

  • sedlaceki. Polyrhachis sedlaceki Kohout, 2006b: 132, figs. 11A-B (w.) NEW GUINEA.

Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.



Dimensions (holotype cited first): TL c. 5.29, 5.59; HL 1.37, 1.40; HW 1.37, 1.40; CI 100, 100; SL 1.62, 1.65; SI 118, 118; PW 1.00, 1.03; MTL 1.93, 1.96 (2 measured).

Clypeus convex in profile, narrowly rounding into medially impressed basal margin. Frontal triangle only weakly impressed. Frontal carinae sinuate with rather flat margins; central area with short frontal furrow. Sides of head in front of eyes weakly convex, strongly converging towards mandibular bases; behind eyes sides rounding into convex occipital margin. Eyes convex, in full face view clearly breaking lateral cephalic outline. Ocelli lacking. Pronotum in dorsal view with humeri widely rounded; greatest pronotal width at mid-length of segment. Mesosoma in profile with pronotum strongly convex; promesonotal suture distinct, rather flat; mesonotal and propodeal dorsa weakly convex, rounding into declivity in even curve; metanotal groove lacking. Petiole with anterior face rounding onto rather blunt dorsal margin, posterior face convex; lateral spines long, slender, directed backwards; dorsal pair reduced to minute denticles. Subpetiolar process acute anteriorly, angular posteriorly. Anterior face of first gastral segment higher than dorsum of petiole, narrowly rounding onto dorsum of segment. Mandibles very finely, superficially sculptured. All body surfaces highly polished, with only very fine, microscopic sculpturation and numerous, very shallow piliferous pits.

Mandibles with several rather short, semierect hairs near masticatory borders. Anterior clypeal margin with a few, anteriorly directed setae medially and several shorter setae laterally. A few, medium length, erect hairs fringing apex of gaster. Extremely short, appressed hairs, arising from numerous pits, in various densities, over all body surfaces.

Colour. Black; mandibles reddish-brown with masticatory borders a shade lighter. Antennae dark brown with distal ends of scapes yellowish-brown and funicular segments progressively lighter towards apex. Legs and gaster rather dark, reddish-brown; tarsi very dark brown.

Type Material

HOLOTYPE: PAPUA NEW GUINEA, Morobe Prov., Bulolo R. Valley, c. 5km N of Wau, 07°17’S, 146°42’E, c. 1000m, 12.vi.1963, rf., J.& M. Sedlácek (worker). PARATYPE: data as for holotype (worker). Holotype (Type QMT99346) in Queensland Museum, paratype in Australian National Insect Collection.