The Ants of Africa
Genus Polyrhachis
Polyrhachis militaris (Fabricius)

Polyrhachis militaris (Fabricius)

return to key {link to the Hymenoptera Name Server} Type location "Tropical Africa" (Formica militaris, Fabricius, 1781: 493, queen; F Smith, 1858b: 72, male; Mayr, 1866b: 886, worker); junior synonyms bruta (Polyrhachis militaris F. st. bruta n.st. [stirps], Santschi, 1912b: 166, queen) from Zaïre, calabarica (Polyrhachis militaris F. subsp. cupreopubescens var. calabarica n. var., Forel, 1907a: 38, worker) from Nigeria (at Old Calabar, Luke, vi.1892), cupreopubescens (Forel, 1879: 120, queen) from "Tropical Africa" (by Sauss, who collected, e.g. Camponotus foraminosus at Cap Vert, Senegal; ssibangensis (Polyrhachis militaris F. subsp. cupreopubescens var. ssibangensis n. var., Forel, 1907a: 38, worker; Santschi, 1910c: 400, queen) from Gabon; and striativentris (P. militaris Fab. race striativentris n.st., Emery, 1892d: 566, worker; Santschi, 1912b: 166, queen) from Ivory Coast (at Assinie, 1886, Ch. Alluaud); unavailable names argentatus (for which dido was an unnecessary replacement name, in Stitz, 1910: 150, worker) from Cameroun at Bibundi, Tessmann, 1905; epinotalis (Polyrhachis militaris F. r. cupreopubescens v. epinotalis n. v., Forel, 1913h: 357, worker), nkomoensis (Polyrhachis (Myrma) militaris F. r. cupreopubescens For.v. nkomoensis n. var., Forel, 1916: 447, all forms), pleurata (Polyrhachis (Myrma) militaris F. st. cupreopubescens For.var. pleurata n. var., Santschi, 1924b: 223, worker) and sankisiana (Polyrhachis militaris F. r. cupreopubescens v. sankisiana n. v., Forel, 1913b: 348, worker) from Zaïre, and transversaria (Polyrhachis militaris F. r. cupreopubescens v. transversaria n. v., Forel, 1901h: 77, worker) from Liberia (location unknown, female, by Hadler); (see Bolton, 1995) .


Fabricius's (11781) description is at {original description}. F Smith's (1866b) description is at {original description}. Mayr's (1866b) description of the worker is at {original description}. Arnold (1924) gave a translation, with an illustration of the petiole; this is at {original description}. Forel's (1879a) description of cupreopubescens (queen) is at {original description} with further notes (worker, TL 9 mm) and calabarica (1907a) at {original description}. Emery's (1892d) description of striativentris is at {original description}. Forel's (1901h) description of transversaria (queen) is at {original description}. Stitz's (1910) description of argentatus is at {original description}. Santschi's (1912b) description of bruta (queen) is at {original description}. Forel's (1913b) description of sankisianus (with limited pubescence) is at {original description}. Forel's (1913h) description of epinotalis (Tl 9-10.5 mm, propodeal spines long, compared with short spines on the type form) is at {original description}. Forel's (1916) description of nkomoensis is at {original description}. Santschi's (1924b) descriptions of the bruta worker, pubescens and sankisiana are at {original description}. As its name implies argentatus (Stitz, 1910) was separated by having goldish pubescence, particularly on the gaster. Bolton's modern description (1973b, not illustrated) is at {original description} and {original description}.


{Polyrhachis militaris dido}The photomontage is of a cotype of Polyrhachis militaris dido from Liberia. The original photographs, together with enlarged images, are from the MCZ, Harvard University, website at - MCZ link.

Arboreal, nesting in rotten parts of standing trees. Forages singly.

Wheeler (1922) also listed findings from Guinea (calabarica at Kakoulima by F. Silvestri), Liberia (argentatus or dido, from Mt. Coffee by R.P. Currie), Sierra Leone (Samlia Falls, by Mocquerys, also cupreopubescens), Togo (Bismarckburg, by Buttner), Nigeria (Old Calabar, by H. Brauns, also cupreopubescens at Old Calabar by Duke), Cameroun (Bibundi by Tessmann; Longji by Paschen; Yaoundé by Scheunemann; Mundame by Conradt, also cupreopubescens from Bibundi by Tessmann and at Molundu by Schultze).


{Polyrhachis militaris}Nigeria specimens (Taylor, 1978: 19). WORKER. TL 10.8-14.1 mm, HL 2.59-3.41, HW 1.96-2.96, SL 3.18-3.89, PW 1.74-2.34
The largest and probably most common and most variable member of the genus. Erect hairs abundant on all surfaces, pubescence dense everywhere, colour of hairs and pubescence variable from grey to silvery, golden or yellow-brown. Alitrunk strongly marginate throughout its length, interrupted at the sutures. Promesonotal suture distinct, metanotal groove impressed. Petiole dorsally with a pair of long spines and laterally with a pair of teeth.

In Nigeria, Bolton (1973b: 313) listed findings at Ilesha (L.E.H. Humfrey), Southern Nigeria (Sampson), Ile-Ife and Evin-Odo (J.T. Medler). In my work it was common on cocoa, on about 1% of trees but in small numbers, and will nest in old dried pods on the trees; its role in the ant mosaic is unknown (Taylor, 1977). Also found on native herbaceous vegetation and trees, and on kola and oil palm. Other Nigerian findings listed by Bolton (1973b) show it to be found throughout the forest zone. Earlier from CRIN, perhaps on < 0.25% of cocoa in pkd collections from two cocoa blocks, W13/2 and W18/1 (Booker, 1968).


{Polyrhachis militaris} From Cameroun, Bolton (1973b) listed it being found at Mt. Cameroun, Bonakande (M. Steele), Ntsama (C.A. Collingwood) and Nkolbisson (L.G. Segers). Lenoir & Déjean (1994) described it as inhabiting dense equatorial forest, mostly nesting high in the trees, in branch axils and organic matter at the base of epiphytes. they also studied colony foundation by queens. The prey included small Tettigonid grasshoppers and termites. It was among the non-dominant species recorded in the Cameroun forest canopy studies at Campo by Dejean and colleagues. They noted it as nesting in the middle stratum only (hollowed branches) with 12 findings on 30 trees examined.

The full list given by Bolton (1973b) - including Ivory Coast, Sierra Leone, Liberia and Benin (all without details) - shows it to be very common throughout the forests of sub-Saharan Africa.

Earlier, Bernard (1952), whose findings were not listed by Bolton (1973b), had reported it from Guinea. He described it as a common and very variable species; with some 12 races distinguished on grounds of colour, with little obvious biological value. Nevertheless he enumerated several varieties as encountered in the Mt. Nimba surveys.
Variety close to the type militaris, but entirely black, with grey reflections - 3 queens and 4 workers from Nion, Yalanzou and Camp IV at 1000 m:
Variety calabarica Forel; head and gaster silver, thorax bronze; more widespread, in the preceding localities, plus Kéoulenta, Thio, and at 1600 m on Mount Tô; 12 workers and 2 queens; known from Nigeria and Congo.
Subspecies cupreopubescens Forel; thorax and gaster bronze, head black or bronzy; this race is largely diffused in Africa, the most common in the surveys, 21 workers, but not found higher than Nion, N'zo and Yalanzou.
Variety dido Wheeler; head and thorax silvery, gaster bronzy; 2 queens, 1 male, 4 workers; from Nion, Kéoulenta, Thio, Yalanzou, Camp IV and Camp I (1600 m); described from Zaïre.
Variety szibangensis Forel; entirely silvery; one queen from Yalanzou; type from French Congo.

The specimen in the photomontage was collected in Cameroun - south-western tropical coastal forest area between Edéa and Campo (McKey Wolbachia project) - Cameroon 106 from location JFK, 24 April 2001, on lianas and dead trunks in a treefall gap. Other images can be seen in the folder at - {original description}.


{Polyrhachis militaris} Found widely in Ghana; Bolton (1973b) gave 13 findings, including CRIG. Room (1971) collected it from cocoa canopy at Mampong Cemetery Farm and in 20/168 samples in his wider survey. Found at Kade by Majer (1975), using pkd, with only 3 workers per sample. Three workers were collected, one by canopy pkd and two on the ground from a block of mature Amelonado cocoa at CRIG by Bigger (1981a). Belshaw & Bolton (1994b) collected 24 workers, as 'tourists' in leaf litter under secondary forest, at Bunso, and under cocoa at Asiakwa. Room (1971) found it to be positively associated with Crematogaster clariventris.

The photomontage is of a specimen from Ghana, collector S Sky Stephens, 2006. Other images can be seen in the folder at {original description};


{Polyrhachis militaris} The photomontage is of a specimen from Central African Republic, Dzangha-Sangha National Park, collected by Philippe Annoyer. Other images can be seen in the folder at {original description}, 24.01.2005, Bord du fleuve Sangha, accostage en face l’île Ebondjo;15h; on Bokoko.

Another and almost identical specimen from the Central African Republic, Dzanga-Sangha can be seen at http://www.antweb.org/specimen.do?name=casent0094091&shot=p1&project=.


{Polyrhachis militaris with Cordomyces}The photomontage is of specimens, one killed by a Cordomyces fungus infection, from the Central African Republic, collected by Philippe Annoyer. Other images can be seen in the folders at {original description}, site FV; and {original description}, Di on a Reduviid bug, 03°55’13.2" N 16°36’46.1" E 536m, 20.01.2005, U.V : 2h-6h, après Sefka (entre Bambio et croisement Nola/Berberati), dans layon forestier; from on a reduviid bug; collected in forest, 1st hour of the morning.

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© 2007, 2008 - Brian Taylor CBiol FIBiol FRES
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