Polyrhachis kohli Forel

Rigato, Fabrizio, 2016, The ant genus Polyrhachis F. Smith in sub-Saharan Africa, with descriptions of ten new species. (Hymenoptera: Formicidae), Zootaxa 4088 (1) : 26-27

Polyrhachis kohli Forel

Polyrhachis kohli Forel, 1916: 454 . Lectotype worker [AntWeb photo: CASENT0910954], two paralectotype worker and one paralectotype gyne (by present designation), DEMOCRATIC REPUBLIC of the CONGO (H. Kohl). (MHNG) [examined].

Diagnosis. A hairy, moderately large revoili -group species with immarginate mesosoma, propodeal dorsum distinctly longer than wide, and long and sinuous standing hairs on the appendages.

Lectotype worker: HL 1.37, HW 0.99, CI 72, SL 1.74, SI 175, FW 0.37, FI 37, PW 0.88, WL 1.87–, HTL 1.70.

Clypeus with relatively narrow protruding rectangular anterior lobe at its anterior margin. Head in full face view elongate oval, with anteriorly converging sides and convex posterior margin. Eyes moderately large and protruding. Mesosoma slender, fully immarginate, both transversely and longitudinally convex. In dorsal view, pro- and mesonotum look weakly transverse and the propodeum twice as long as wide, when considering as a reference width the outer ends of the propodeal ridges. In profile, propodeal dorsum a little longer than the declivity. Pronotal teeth small, their anterior edge almost perpendicular to the longitudinal axis of the body. Propodeal dorsum and declivity separated by two moderately developed ridges, leaving a narrow gap between them; the gap is slightly narrower than each ridge. Promesonotal and metanotal sutures weak. Petiole with a dorsal pair of moderately long, diverging spines and a lateral pair of small sharp teeth; the dorsal margin of the petiole almost straight and about 1.5 times as long as each spine. First gastral tergite anteriorly concave.

Mandibles weakly sculptured: proximally subopaque and shagreened and becoming apically smoother. Clypeus superficially reticulate. Head dorsum mostly irregularly longitudinally rugulose. Mesosoma and petiole reticulate-punctate, mesosomal dorsum with a more or less developed superimposed longitudinal rugulation. Appendages finely reticulate-punctate. Gaster finely reticulate and weakly shining.

Standing hairs fine, abundant and mostly pale and flexuous throughout. Longest hairs on tibiae approaching the maximum tibial width; longest hairs on scapes about thrice as long as the scape diameter. Pubescence whitish, moderately long and dense on most body surfaces, but never hiding sculpturation.

Body black, mandibles brown, becoming almost testaceous apically. Legs mostly piceous, with tibiae, except basally, and apical tarsal segments ferrugineous. Antennae with mostly piceous scape; funiculus ferrugineous, except the darkened base of its basalmost 4-5 joints.

Paralectotype workers (n=2): HL 1.28–1.40, HW 0.94–1.02, CI 73, SL 1.65–1.70, SI 167–176, FW 0.35–0.37, FI 36–37, PW 0.83–0.87, WL 1.76–1.83, HTL 1.43–1.62.

Paralectotype gyne: HL 1.63, HW 1.15, CI 71, SL 2.05, SI 178, FW 0.42, FI 37, ScW 1.45, MnL 1.87, WL 2.63, HTL 2.05.

Comment. Bolton’s description (1973) of P. volkarti must be referred to kohli . The latter is a valid species and not a synonym of P. v o l k ar t i Forel as proposed by Bolton (1973). The main distinctive features of gynes (P. v o l k ar t i was described on a single gyne only) are as follows:

Polyrhachis kohli (paralectotype gyne) Polyrhachis volkarti (type gyne)

Standing hairs longer and often sinuous. Length of longest Standing hairs shorter, straight to uniformly curved. Length of standing hairs on extensor tibial surface approaching the tibial longest standing hairs on extensor tibial surface at most width at midlength. Scutum and scapes with long, flexuous approaching half of the tibial width at midlength. Scutum and hairs, often more than twice as long as scape diameter. scapes with relatively short and straight hairs, at most about

1.5 as long as scape diameter.

Propodeal ridges much closer to one another, they are Propodeal ridges widely separated, the space between them separated by a space slightly larger than the length of a single much larger than the length of a single ridge. The distance ridge. The distance between ridges’ outer ends is less that the between ridges’ outer ends is larger than the length of the length of the propodeal dorsum. propodeal dorsum.

In profile, propodeal dorsum about as long as the declivity. In profile, propodeal dorsum distinctly shorter than the declivity.

The three workers of the type series of P. kohli are evidently conspecific with the gyne and their propodea appear unusually narrow and elongate in dorsal view when compared to similar species (see also under submarginata ).