Polyrhachis queenslandica

Polyrhachis queenslandica
Scientific classification
Kingdom:	Animalia
Phylum:	Arthropoda
Class:	Insecta
Order:	Hymenoptera
Family:	Formicidae
Subfamily:	Formicinae
Tribe:	Camponotini
Genus:	Polyrhachis
Subgenus:	Myrmothrinax
Species:	P. queenslandica
Binomial name
	Polyrhachis queenslandica; Emery, 1895 Specimen Labels
Synonyms
	Polyrhachis dahli unisculpta Viehmeyer, 1914;

This species is an arboreal nester, using silk to join the leaves of various lowland rainforest trees and shrubs (Kohout 1999, 2000; Robson & Kohout 2005, 2007; Kohout, 2012).

Identification

As indicated by Kohout (1994), the most obvious differences between Polyrhachis delicata and P. queenslandica are their colour and the orientation of their propodeal spines. However, due to a high degree of variability, notably within Queensland populations of both species, these characters can be unreliable and, while both species are usually separable, no single character is universally diagnostic. The propodeal spines in P. delicata are generally more strongly upturned, but the actual angle of elevation varies between specimens, even those of the same nest series. The propodeal spines in P. queenslandica are distinctly less elevated with only a small amount of variation between the specimens examined. The colour of the body appears to be a more reliable character to separate the species but only in fully pigmented specimens. A mostly red or reddish-brown mesosoma, gaster and appendages, contrasting with a darker head (almost black in some specimens) characterises P. delicata, while the body in P. queenslandica is mostly uniformly black or very dark reddish-brown. The sculpturation of the head and mesosoma in P. delicata is rather distinctly reticulate-punctate and opaque, while it is markedly more finely and closely punctate in P. queenslandica. The petiolar node in P. delicata is relatively slim and distinctly narrows dorsally in lateral view, with the anterior face smoothly curving onto the petiolar dorsum in an uninterrupted line that incorporates the anterior edge of the dorsoposteriorly elevated median spine. In contrast, the petiolar node in P. queenslandica is distinctly thicker in lateral view, with the anterior face curving onto a virtually flat dorsum and the median petiolar spine dorsoposteriorly elevated at a distinctly steeper angle. The latter character does not serve to separate the queens of the two species, however, the median petiolar spine in the queen of P. queenslandica is simply pointed, while its apex is clearly emarginated in P. delicata.

Keys including this Species

Key to Australian Polyrhachis (Myrmothrinax) species

Distribution

Latitudinal Distribution Pattern

Latitudinal Range: -3.089444444° to -19°.


North Temperate	North Subtropical	Tropical	South Subtropical	South Temperate

Source: AntMaps

Distribution based on Regional Taxon Lists

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

The distribution of P. queenslandica is divided between New Guinea and northern Queensland, where it overlaps with Polyrhachis delicata. The syntypes of the synonym P. dahli unisculpta, collected at Wareo on Huon Peninsula, and a single worker from Kokoda, are the only known records of the species from New Guinea. In Australia it is relatively common, though somewhat less abundant than P. delicata, particularly towards the southern limit of its distribution. The known Australian range extends from the tip of Cape York Peninsula south to about the Paluma Range.

Distribution based on AntMaps

Distribution based on AntWeb specimens

Check data from AntWeb

Countries Occupied

Number of countries occupied by this species based on AntWiki Regional Taxon Lists. In general, fewer countries occupied indicates a narrower range, while more countries indicates a more widespread species.

Estimated Abundance

Relative abundance based on number of AntMaps records per species (this species within the purple bar). Fewer records (to the left) indicates a less abundant/encountered species while more records (to the right) indicates more abundant/encountered species.

Biology

Castes

Males and immature stages (eggs, larvae and pupae) in QM spirit collection. (Kohout 2012)

Images from AntWeb


Syntype of PolyrhachisÂ dahlii unisculpta. Worker. Specimen code casent0905838. Photographer Z. Lieberman, uploaded by California Academy of Sciences.	Owned by MSNG, Genoa, Italy.


Worker. Specimen code casent0906580. Photographer Estella Ortega, uploaded by California Academy of Sciences.	Owned by NHMUK, London, UK.

Nomenclature

The following information is derived from Barry Bolton's Online Catalogue of the Ants of the World.

queenslandica. Polyrhachis queenslandica Emery, 1895g: 356 (w.) AUSTRALIA. Crawley, 1921: 96 (q.m.). Combination in P. (Myrmothrinax): Emery, 1925b: 183. Senior synonym of unisculpta: Kohout, 1998: 510. See also: Kohout, 2012: 53.
unisculpta. Polyrhachis dahli var. unisculpta Viehmeyer, 1914b: 48 (w.q.) NEW GUINEA. Combination in P. (Myrmothrinax): Emery, 1925b: 183. Junior synonym of queenslandica: Kohout, 1998: 510.

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

Description

Worker

Kohout (2012) - (syntypes [5] cited first): TL c. 5.95-6.70, 5.09-6.71; HL 1.50-1.65; 1.34-1.65; HW 1.26-1.42, 1.15-1.47; CI 82-88, 82-89; SL 1.90-2.03, 1.72-2.12; SI 141-153, 141-155; PW 0.87-0.97, 0.75- 1.00; MTL 2.06-2.28, 1.78-2.40 (74 measured).

Anterior clypeal margin with wide median truncation flanked by small teeth. Clypeus with median carina; straight in profile, posteriorly rounding into moderately impressed basal margin. Frontal triangle distinct. Frontal carinae sinuate with margins only weakly raised at midlength; central area weakly convex with poorly indicated frontal furrow. Sides of head in front of eyes converging towards mandibular bases in weakly convex line; behind eyes sides widely rounding into convex occipital margin. Eyes convex, in full face view clearly breaking lateral cephalic outline. Ocelli lacking; position of lateral pair indicated in some specimens by shallow punctures in sculpturation. Pronotal dorsum often with poorly defined median longitudinal depression; pronotal humeri angular with lateral margins converging posteriorly into distinct promesonotal suture. Dorsum of mesosoma with lateral margins converging posteriorly into well defined metanotal groove. Lateral margins of propodeum subparallel, terminating in obliquely elevated, subparallel, acute spines. Petiole with anterior face straight, posterior face weakly convex; petiolar dorsum a virtually flat platform, armed with two widely diverging, short lateral spines and a long, acute, dorsoposteriorly elevated median spine. Anterior face of first gastral segment distinctly higher than full height of petiole, widely rounding onto gastral dorsum.

Mandibular bases finely longitudinally striate-rugose, sculpture distinctly finer and polished towards masticatory borders. Head mostly finely reticulate-punctate, feebly polished. Intensity of sculpturation somewhat increasing posteriorly, with mesosoma and petiole more closely and distinctly reticulate-punctate. Gaster very finely shagreened, highly polished.

Mandibular masticatory borders with several, semierect, golden hairs and very short, closely appressed hairs towards bases. Anterior clypeal margin with a fringe of a few, rather short setae; clypeus with pair of relatively short hairs near anterior and basal margins; slightly longer, semierect hairs along frontal carinae, on vertex and front coxae. Pilosity and pubescence almost completely absent from mesosoma and petiole. Gastral venter and apical gastral tergites with numerous, relatively long hairs. Dorsum of gaster with very short, closely appressed, much diluted golden pubescence.

Colour. Head and body in fully pigmented specimens mostly black or very dark reddish-brown. Mandibles, except masticatory borders, clypeus and central area, legs, including coxae and base of gastral dorsum usually dark reddish-brown; funicular segments progressively lighter, yellowish-brown, towards antennal apex. Mandibular masticatory borders, anterior clypeal margin and frontal carinae narrowly lined with black or very dark brown.

Queen

Kohout (2012) - TL c. 8.11-9.17; HL 1.87-1.96; HW 1.59-1.68; CI 84-87; SL 2.25-2.34; SI 134-144; PW 1.58-1.68; MTL 2.46-2.59 (10 measured). Apart from sexual characters, closely resembling worker except: pronotal humeri obtusely angular. Mesoscutum about as wide as long, lateral margins converging anteriorly and forming moderately rounded anterior margin; median line distinct, bifurcate dorsally; parapsides flat, only marginally raised posteriorly. In profile, anterior face of mesoscutum widely rounding onto weakly convex dorsum. Mesoscutellum raised above dorsal plane of mesosoma, strongly rounding posteriorly into distinctly impressed metanotal groove. Propodeal dorsum with lateral margins indistinct; propodeal spines somewhat flattened dorsally, about as long as distance between their bases, oblique to main axis of body; their inner margins continued medially and forming an open ‘U’ in anterior view. Petiole with anterior face rounding onto posteriorly elevated dorsum; spines shorter and thicker than in worker; middle spine only marginally longer than lateral pair, acute.

Type Material

Polyrhachis queenslandica type material.
Syntype workers. Type locality: AUSTRALIA, QUEENSLAND, Kamerunga (M. Podenzana), Musee d'Histoire Naturelle Genève, Museo Civico di Storia Naturale, Genoa (examined by Kohout, 2012).

Polyrhachis dahli unisculpta type material.
Syntype workers. Type locality: NEW GUINEA, Huon Pen., Wareo, Berlin Museum für Naturkunde der Humboldt-Universität (examined by Kohout, 2012).

Polyrhachis queenslandica: Syntype, worker(s), Kamerunga, Queensland, Australia, Museo Civico di Storia Naturale, Genoa.
Polyrhachis dahli unisculta Viehmeyer, 1914: Syntype, workers, queen, Wareo, Morobe Province, Papua New Guinea, Berlin Museum für Naturkunde der Humboldt-Universität.

References

Crawley, W. C. 1921. New and little-known species of ants from various localities. Ann. Mag. Nat. Hist. 9(7): 87-97 (page 96, queen, male described)
Emery, C. 1895h. Descriptions de quelques fourmis nouvelles d'Australie. Ann. Soc. Entomol. Belg. 39: 345-358 (page 356, worker described)
Emery, C. 1925d. Hymenoptera. Fam. Formicidae. Subfam. Formicinae. Genera Insectorum 183: 1-302 (page 183, Combination in P. (Myrmothrinax))
Kohout, R. J. 1998. New synonyms and nomenclatural changes in the ant genus Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Mem. Qld. Mus. 42: 505-531 (page 510, Senior synonym of unisculpta)
Kohout, R.J. 2012. A review of the Australian Polyrhachis ants of the subgenera Myrma Billberg, Myrmatopa Forel, Myrmothrinax Forel and Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum – Nature 56(1):25-59.

References based on Global Ant Biodiversity Informatics

Emery C. 1895. Descriptions de quelques fourmis nouvelles d'Australie. Annales de la Société Entomologique de Belgique 39:345-358.
Janda M., G. D. Alpert, M. L. Borowiec, E. P. Economo, P. Klimes, E. Sarnat, and S. O. Shattuck. 2011. Cheklist of ants described and recorded from New Guinea and associated islands. Available on http://www.newguineants.org/. Accessed on 24th Feb. 2011.
Klimes P., P. Fibich, C. Idigel, and M. Rimandai. 2015. Disentangling the diversity of arboreal ant communities in tropical forest trees. PLoS ONE 10(2): e0117853. doi:10.1371/journal.pone.0117853
Kohout R. J. 1998. New synonyms and nomenclatural changes in the ant genus Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum 42: 505-531
Kohout R. J. 2000. A review of the distribution of the Polyrhachis and Echinopla ants of the Queensland wet tropics (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum 46: 183-209
Kohout R. J. 2012. A review of the Australian Polyrhachis ants of the subgenera Myrma Billberg, Myrmatopa Forel, Myrmothrinax Forel and Polyrhachis Fr. Smith (Hymenoptera: Formicidae: Formicinae). Memoirs of the Queensland Museum 56(1): 25-59.
Mann, W.M. 1919. The ants of the British Solomon Islands. Bulletin of the Museum of Comparative Zoology of Harvard College 63: 273-391
Robson Simon Database Polyrhachis -05 Sept 2014
Snelling R. R. 2000. Ants of the Wapoga river area, Irian Jaya, Indonesia. In Mack, Andrew L. and Leeanne E. Alonso (eds.). 2000. A Biological Assessment of the Wapoga River Area of Northwestern Irian Jaya, Indonesia. RAP Bulletin of Biological Assessment 14, Conservation International, Washington, DC.
Viehmeyer H. 1912. Ameisen aus Deutsch Neuguinea gesammelt von Dr. O. Schlaginhaufen. Nebst einem Verzeichnisse der papuanischen Arten. Abhandlungen und Berichte des Königlichen Zoologischen und Anthropologische-Ethnographischen Museums zu Dresden 14: 1-26.
Viehmeyer H. 1914. Neue und unvollständig bekannte Ameisen der alten Welt. Archiv für Naturgeschichte (A)79(12): 24-60.