Polyrhachis
ayousi Taylor new species
  Type location Central
African Republic
WORKER DESCRIPTION:
At first sight,
this appears to be close to Polyrhachis
militaris but it is separable on a number of
counts. Most distinctive is the propodeum which has long upcurved
spines and a sharp
transverse carina between the bases of the spines. In
Bolton's key (1973b) this separates P. militaris
(which lacks a transverse ridge) from Polyrhachis
latispina. The latter, however, otherwise is quite
distinctive.
I have sighted specimens of P.
militaris from six countries (Cameroun, CAR, Gabon, Liberia,
Ghana and Nigeria) and overall the size of the new species is near the
lower end of the P. militaris size range (Bolton,
1973b); see also the Antweb
images of militaris varieties.
However, the new species has a much narrower pronotum, measured
at the base of the more flared spines, SPW 170-176; with the latter in P.
militaris SPW = 135).
The propodeal
spines appear to be significantly larger than on any of the "varieties"
of militaris. The overall dense yellow-gold
pubescence also seems distinctive, especially the very dense coarse
covering on the alitrunk dorsum. The head in full-face view is ovoid
with a strongly convex occipitum. In P. militaris
the full face view generally is straight-sided or nearly so and the
occiput is transverse, often near straight. The funiculus gradually
thickens from base to apex, whereas it is more slender and uniformly
narrow thoughout its length in P. militaris.
The underlying sculpturation mostly is concealed by the dense
pubescence but that on the head is of a fine dense spiculation (rather
than the fine striation seen on P. militaris) and
the mandibles are more coarsely striate.
Holotype
- TL ca 11.4 mm, HL 2.50, HW 2.00, CI 80; SL 3.10, SI 155; EL (eye
length) 0.5, OI 25; PW 1.40 (spine width at apex 2.40; ratio SPW =170),
HF (hind-leg femur) 3.80
Specimen 2 - TL ca 11.2 mm, HL 3.00,
HW 2.20, CI 73; SL 3.50, SI 159; EL 0.60, OI 28; PW 1.50 (spine width
at apex 2.65, ratio 176), HF 3.60
Apparently
an inhabitant of primary forest canopy, as collected at 38 m above
ground on Triplochiton scleroxylon, Sterculariaceae.
Collection details: Camp 6 GR; 02°55’04.8" N
16°10’09.7" E, 450m environ; 25.02.2005, U.V :
18h30-5h30, à 38m du sol dans un Ayous (Triplochiton
scleroxylon, Sterculariaceae), orage à partir de
5h40 et ce jusqu’à midi, collected by Philippe
Annoyer.
The name is derived from it being collected on an Ayous.
QUEEN: see below, two specimens.
Specimens deposited in the Oxford University Museum of
Natural History.
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Note - This may well be the same as Polyrhachis
militaris F. r. cupreopubescens v. epinotalis
n. v., Forel, 1913h: 357, worker) from Zaïre, Lumbumbashi
(Elizabethville),
Miss. Agric., Leplae; Forel's (1913h) description of epinotalis
(TL 9-10.5 mm, propodeal spines long, compared with short spines on the
type form) is at  . Antweb images of epinotalis are shown below. Also
shown is a very similar form from Kenya.
Santschi (1924b: 22) in his key to varieties of P. militaris separated P. militaris stirps epinotalis
For. from all the other
varieties by having the sides of the head narrowing immediately behind
the eyes but gave no other information. Bolton (1973b: 313) merely
noted this form as an unavailable name that he had examined. Antweb
have it as a "Junior synonym of P.
militaris" according to Dorow (1995a: 36). Dorow's paper is
titled a "Revision of the ant genus Polyrhachis
... on subgenus level with keys, checklist of species and bibliography.
His keys below subgenus level were to Asian and Australasian species.
It is totally lacking in notes on methodology and lacks the norms of
taxonomic revision. His species checklist therefore has no
verifiable merit. The Antweb page then has "Revived from synonymy
and raised to species: new status (unpublished).
" but without any statement of authority. The images were uploaded on
31 March 2014.
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Queen
As with the queen of Polyrhachis militaris
(Bolton, 1973b),
the spines on the alitrunk and petiole are reduced. The transverse
ridge on the propodeum is visible, as in the worker.
Other differences from the militaris
queens, I have from the
Central African Republic are: a larger head, with shiny black, striated
mandibles; in full face view the head lacks well defined longitudinal
striations; the promesonotum im lateral view is more domed; distinctive
parallel rugulation on the propodeum dorsum; the
petiole has shorter thicker based dorsal spines but better developed
lateral spines.
Queen labelled JW;
03°01'49.5" N 16°08'31.7" E 567 m; Camp 2; 19.x.2008 18h-2h; A la base
du kungu, à 50 m du camp
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The photomontage is
of the holotype specimen from Central
African Republic, CAR GR-01 
Second
worker specimen,
The
photomontage of the type worker of epinotalis is
collated from 
The
photomontage of a worker from Kenyan rainforest, labelled as 