Polyrhachis strumosa

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

Polyrhachis strumosa casent0217438 p 1 high.jpg

Polyrhachis strumosa casent0217438 d 1 high.jpg

Specimen Labels

Nothing is known about the biology of Polyrhachis strumosa.


With its rather massive mesosoma, Polyrhachis strumosa is similar to Polyrhachis hybosa. However, they differ in a number of characters, including the outline of mesosoma which, in Polyrhachis strumosa, features a very short pronotal summit and rather high propodeal declivity. In Polyrhachis hybosa the summit of pronotal dorsum is longer and the propodeal declivity distinctly lower. Also, the pronotal dorsum in Polyrhachis strumosa is widest just behind the more-or-less angular humeri, while the pronotal humeri in Polyrhachis hybosa are widely rounded with the pronotal dorsum widest at its mid-length. The petiolar scale in Polyrhachis strumosa is distinctly transverse, while it is virtually quadrate in Polyrhachis hybosa. (Kohout 2006)

Keys including this Species


Only known from the type locality (see below).

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


Only known from the type series.



Known only from the worker caste.


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

  • strumosa. Polyrhachis strumosa Kohout, 2006b: 132, figs. 11E-F (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. 6.80, 6.30-7.26; HL 1.68, 1.53-1.72; HW 1.62, 1.53-1.65; CI 96, 94-96; SL 2.28, 2.11-2.34; SI 141, 137-143; PW 1.50, 1.29-1.54; MTL 2.71, 2.53-2.84 (8 measured).

Clypeus in profile weakly convex, posteriorly rounding into rather flat basal margin. Frontal triangle indistinct. Frontal carinae sinuate with raised margins; central area concave medially with rather distinct frontal furrow. Sides of head in front of eyes convex, converging towards mandibular bases; behind eyes sides rounding into convex occipital margin. Eyes convex, in full face view marginally exceeding lateral cephalic outline. Ocelli lacking. Pronotum in dorsal view with humeri distinctly subangular; greatest width of pronotal dorsum just behind shoulders. Mesosoma in profile with pronotum rising towards short summit in rather steep, almost straight line; promesonotal suture distinct; mesonotal dorsum very weakly convex, sloping down posteriorly to feebly indicated metanotal groove; propodeal dorsum weakly convex, rounding into relatively high, virtually vertical declivity. Petiole very broad, transverse, anterior face in profile almost straight, posterior face weakly convex; dorsum armed with four spines; lateral pair slightly longer. Subpetiolar process anteriorly acute, weakly concave posteriorly. Anterior face of first gastral segment straight, narrowly rounding onto dorsum of segment.

Mandibles longitudinally rugose with numerous piliferous pits. Head, mesosoma and gaster shagreened, sculptural intensity increasing laterally to become reticulate-rugose, notably on meso- and metapleurae. Petiole finely, mostly transversely wrinkled dorsally, sculpture coarser at base. Numerous shallow punctures and piliferous pits in various densities over all dorsal surfaces.

Mandibles with several short semierect hairs at masticatory borders. Anterior clypeal margin with a few anteriorly directed setae medially and very few shorter setae laterally. A few pairs of medium length, erect hairs near anterior and basal clypeal margins and along frontal carinae. Gaster with numerous, medium length, erect hairs lining posterior margins of apical segments, more abundant on ventral surfaces.

Colour. Black; mandibular teeth, condylae and distal ends of antennal scapes reddish-brown. Funiculi brown with distal segments progressively lighter towards apices; tip of apical segments light yellowish-brown. Legs medium to dark reddish-brown with fore and middle tibiae a shade lighter; tarsi very dark brown or black.

Type Material

HOLOTYPE: PAPUA NEW GUINEA, East Sepik Prov., Maprik, 03°36’S, 143°03’E, 150m, 29.xii.-17.i.1960, T.C. Maa (worker). PARATYPES: data as for holotype (7 workers). Holotype and 1 paratype in Museum of Comparative Zoology; 2 paratypes in The Natural History Museum; 1 paratype each in Australian National Insect Collection, Bernice P. Bishop Museum, California Academy of Sciences and Queensland Museum.