Hypoponera bulawayensis (Forel) Bolton, B. & Fisher, B. L., 2011

Bolton, B. & Fisher, B. L., 2011, Taxonomy of Afrotropical and West Palaearctic ants of the ponerine genus Hypoponera Santschi (Hymenoptera: Formicidae)., Zootaxa 2843, pp. 1-118 : 31-33

Hypoponera bulawayensis (Forel) stat. n.

(Figs 13 – 15)

Ponera ragusai st. bulawayensis Forel , 1913a: 203. Holotype worker, ZIMBABWE: Bulawayo, 23.iii.13, no. 158 (G. A r n o ld) (MHNG) [examined]. Stat. n. [Combination in Hypoponera : Bolton, 1995: 213.]

WORKER. Measurements: HL 0.54 – 0.55, HW 0.40 – 0.41, HS 0.475 – 0.480, SL 0.36 – 0.37, PrW 0.29 – 0.32, WL 0.72 (WL of holotype not measurable because head plus propleuron, prosternum and forelegs are detached as a unit and glued down so that they are partially on top of the pronotum), HFL 0.33 – 0.34, PeNL 0.20, PeH 0.30, PeNW 0.22, PeS 0.240 (2 measured). Indices: CI 73 – 76, SI 90, PeNI 70 – 76, LPeI 67, DPeI 110.

Eyes absent. Scape relatively long (SI 90) but when laid straight back from its insertion in full-face view its apex distinctly fails to reach the midpoint of the posterior margin; SL/HL 0.65 – 0.69. Funiculus distinctly with 5 enlarging apical segments. Reticulate-punctate sculpture of cephalic dorsum fine and dense. Pronotal dorsum with minute superficial punctulae, almost smooth, obviously less strongly and densely sculptured than cephalic dorsum. Mesonotum and dorsum of propodeum almost smooth, shiny and almost entirely devoid of punctulae. No trace of metanotal groove on dorsum of mesosoma. Mesonotal-mesopleural suture absent from side of mesosoma. Propodeum rounded between declivity and side. Posterior surface of petiole node without short cuticular ridges that radiate from just above the peduncle. Node of petiole in profile distinctly stout-nodiform, relatively long and low. Anterior and posterior faces of node in profile slightly convergent to almost parallel; length of node just above the anterior tubercle is slightly greater than length of dorsum; dorsal surface is very weakly convex. Subpetiolar process simple, with a shallow, obtuse ventral angle but without a sharply defined ventral tooth or prominent acute angle. In dorsal view petiole node relatively long, only 10 percent broader than long (DPeI 110), with posterior face transverse; sides and anterior face form a single thickly D-shaped convex surface, with the sides slightly convergent anteriorly. Maximum width of first gastral tergite in dorsal view 0.36; width of second gastral tergite at its midlength 0.38 – 0.40. Cross-ribs present at base of cinctus of second gastral tergite. Sides of second gastral tergite in dorsal view almost straight. Midline length of second gastral posttergite, from posterior margin of cinctus to apex, is equal to the maximum width of the segment. Disc of second gastral tergite finely microreticulate. First and second gastral tergites dorsally pubescent and with a number of very short standing setae that project just above the level of the pubescence. Full adult colour yellow.

The relatively long, low petiole node is characteristic of bulawayensis . In section 1 of the abeillei group the bulawayensis LPeI 67 is approached only by angustata , for which a maximum LPeI of 70 has been recorded. In all others the node in profile is much taller and shorter from front to back, with a combined range of LPeI 37 – 59. H. angustata is not likely to be confused with bulawayensis , as the former has shorter scapes, SI 71 – 79, and conspicuously has only four enlarged apical funicular segments, as opposed to SI 90 and five enlarging funicular segments in bulawayensis .

In dorsal view the petiole node of bulawayensis has DPeI 110, very long in proportion to its width. This is approached only by regis (DPeI 100), angustata (DPeI 100 – 125) and perparva (DPeI 108 – 120). Of these, regis is easily separated by the characters in the key while the last two are smaller species (HW 0.35 or less) and as noted above the first has only four conspicuously enlarged apical funicular segments. Also, both these small species have scapes that are relatively markedly shorter, SI 71 – 80, as opposed to SI 90 in bulawayensis . Discounting these three species, the remainder of section 1 of the abeillei group shows a combined DPeI of 133 – 187, far exceeding bulawayensis. As frequently happened in the early taxonomy of Afrotropical Hypoponera , the name bulawayensis was originally associated with a species to which it is not actually related, in this case ragusai .

Only two specimens, from widely separated localities, are known. Both have exactly the same petiole measurements, SI, LPeI and DPeI. With the petiole node in profile the Tanzania specimen has its anterior and posterior faces slightly more convergent dorsally than in the holotype and its PrW is slightly greater, resulting in a slightly lower PeNI.

Material examined. Zimbabwe: Bulawayo (G. Arnold). Ta n z a n i a: Pwani Reg., Mlola For., Mafia I. (Hawkes, Mlacha & Ninga).