Hypoponera camerunensis (Santschi)

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 : 33-34

Hypoponera camerunensis (Santschi)

(Figs 16 – 18)

Ponera abeillei var. cammerunensis Santschi , 1914b: 321. Syntype worker, CAMEROUN: Victoria (F. Silvestri) (NHMB) [examined]. [Combination in Ponera (Hypoponera) and spelling justifiably emended to camerunensis : Santschi, 1938: 79. Combination in Hypoponera and raised to species: Taylor, 1967: 12.]

NOTE. In the original description of camerunensis, Santschi states that the petiole is as long as broad in dorsal view. This is incorrect as the petiole in the syntype is conspicuously broader than long and indeed is broader than long (i.e. DPeI>100) in almost all Afrotropical Hypoponera .

WORKER. Measurements: HL 0.51 – 0.57, HW 0.42 – 0.46, HS 0.470 – 0.530, SL 0.32 – 0.40, PrW 0.32 – 0.37, WL 0.68 – 0.76, HFL 0.32 – 0.41, PeNL 0.16 – 0.18, PeH 0.30 – 0.33, PeNW 0.23 – 0.28, PeS 0.227 – 0.260 (25 measured). Indices: CI 78 – 85, SI 75 – 91, PeNI 69 – 81, LPeI 48 – 56, DPeI 133 – 173.

Eyes absent. In full-face view apex of scape, when laid straight back from its insertion, fails to reach, or just touches, the midpoint of the posterior margin; SL/HL 0.63 – 0.72. Funiculus distinctly with 5 enlarging apical segments. Metanotal groove often entirely absent from dorsum of mesosoma but in some a remnant of its former path may be represented by a slight change of slope or vestigial indentation of the cuticle. Mesonotal-mesopleural suture absent from side of mesosoma. Propodeal declivity separated from sides by bluntly rounded curves or moderately defined blunt angles; never with an acute raised margin or a sharp carina. Posterior surface of petiole node without short cuticular ridges that radiate from just above the peduncle. Node of petiole in profile short-nodiform, the anterior and posterior faces converge dorsally so that length of node just above anterior tubercle is usually noticeably greater than length of dorsum; dorsal surface is almost flat to shallowly convex. Subpetiolar process in profile conspicuous; usually with a descending anterior face that terminates in a distinct ventral angle or broad tooth that is variably developed. Maximum width of first gastral tergite in dorsal view is noticeably less than width of second gastral tergite at its midlength. Sides of second gastral tergite shallowly convex in dorsal view. Midline length of second gastral posttergite, from posterior margin of cinctus to apex, is less than the maximum width of the segment. Cross-ribs at base of cinctus of second gastral tergite short, fine and densely crowded. Disc of second gastral tergite with densely crowded, small, superficial punctures so that the surface appears microreticulate at lower magnifications. First and second gastral tergites dorsally pubescent and with a number of short standing setae that project just above the level of the pubescence. Full adult colour yellow.

As in coeca there is sufficient variation among samples of camerunensis to imply that more than one sibling species may currently be hidden within this name. In some (including the syntype) the scape apex, when laid straight back in full-face view, fails to reach the midpoint of the posterior margin of the head by a noticable distance. In others it fractionally fails to reach the midpoint, while in most of the Ugandan specimens the scape apex just touches the midpoint. Coupled with this are differences in petiole shape and width (note in particular the large range of DPeI) and in the appearance and degree of development of the subpetiolar process. For the present all are treated as constituting a single species, but more material and further analysis is certainly needed. In general appearance camerunensis is a larger version of the more widespread and common coeca , as indicated in the key. The similar scape and petiole variation in both demands a more detailed assessment in the future.

Material examined. Cameroun: Victoria (Silvestri); Korup N.P., Mundemba (B.L. Fisher); Prov. Sud-Ouest, Bimbia For., Limbe (B.L. Fisher). Gabon: Prov. Ogooue-Maritime, Res. Monts Doudou, nr Doussala (B.L. Fisher); Prov. Estuaire, Pointe Ngombe, Ekwata (B.L. Fisher). Democratic Republic of Congo: Epulu (S.D. To r t i). Uganda: Bushenyi Distr., Kalinzu For. (S. Yamane).