Polyrhachis laboriosa F.Smith
Type location Sierra Leone (F Smith, 1858b: 72,
illustrated, worker; Mayr, 1896: 250, queen & male), collector
D.F. Morgan; junior synonyms architecta (Santschi, 1924b:
224, worker) from Zaïre, collected at Kondue, by
Luja; and hortulana (Arnold, 1955: 735, illustrated,
worker) from Uganda; (see Bolton, 1995)
 .
F Smith's (1858b) description, with a drawing of the petiole, is
at  .
Mayr's (1896) description of the male is at
 .
Santschi's (1924b) description of architecta is at
 .
Arnold's (1955) description of hortulana is at
 .
Bolton's modern description (1973b) is at
WORKER (Nigeria specimens) - TL 10.2-11.6 mm, HL 2.15-2.25, HW
1.56-1.81, SL 2.85-2.3.34, PW 1.19-1.36
Distinguished by a petiole which has a single pair of long dorsal
spines with strongly hooked apices. All dorsal surfaces with
numerous erect hairs, varying in colour from grey to
golden-yellow. Pubescence dense usually grey on the head and
alitrunk, golden or bronzy on the gaster. Alitrunk marginate
throughout its length, interrupted by impressions at the sutures.
Pronotum and propodeum weakly concave transversely (see also
Bolton, 1973b: 308, illustrated, petiole only).
Wheeler (1922) listed findings from Ivory Coast (Assinie
by C. Alluaud), Ghana (by Ganger), Togo (Bismarckburg,
by Conradt), Nigeria (Lagos, F. Silvestri), Cameroun
(Sjöstedt, H. Brauns, at Bipindi by Zenker, at Bibundi by
Tessmann), also elsewhere in tropical Africa. Forel (1911f) found
specimens in the Congo Museum from Zaïre, Congo da
Lemba, by Mayné.
Bernard (1952) reported it from Guinea, with findings
from the Mt. Nimba surveys, forest and savanna areas; Nion, N'Zo,
Sérengbara, Thio, Yanlé, Yalanzou; moderately
abundant, form close to the type.
A fairly common arboreal species which constructs nests of
vegetable fragments and small twigs bound together by silk and
fungal hyphae and adherent to the undersides of leaves or in the
fork of small branches. Appears to be restricted to forested
areas, although Lenoir & Déjean (1994) noted that it
lives on pioneer trees and the edge of forest tracks in Cameroun.
In Nigeria, occasionally found foraging on cocoa, also
on kola. Bolton (1973b) listed his own finding at CRIN, plus
others at Lagos (G. Strachan) and Itu (W.A.C. Cockburn). Earlier
from CRIN, perhaps on 1-2% of cocoa in pkd collections from two
cocoa blocks, W13/2 and W18/1 (Booker, 1968).
Bolton (1973b) also lists several findings in Ghana; at
Bibianaha (Spurrel), Ankasa Forest Reserve (O.W. Richards), near
Kumasi (B.M. Gerard), CRIG (C.A. Collingwood), Bawdna (N.D. Jago)
and Adeiso (P.M. Room). Other reports are by Majer (1975, 1976b),
using pkd, with 51-135 workers per sample, at Kade. Also on cocoa
mistletoe and in the canopy survey by Room (1971, 1975), who found
in 19/168 samples and positively associated with Tetramorium
aculeatum.
Bolton's very wide listing (1973b) indicates that it can be
found throughout the forests of sub-Saharan Africa. |
The
photomontage is of a specimen from the Central African
Republic, Dzanga-Sangha NP; 22.ii.2005, Camp 6; edge r
Mossoumba; 02°55’04.8" N 16°10’09.7"
E 450m environ; 1500 h, collector Philippe Annoyer. Other images
can be seen in the folder at -
