Hypoponera inaudax (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 : 61-62

Hypoponera inaudax (Santschi)

(Figs 58 – 60)

Ponera inaudax Santschi , 1919: 83. Holotype worker, DEMOCRATIC REPUBLIC OF CONGO: Yambuya, 26.xi., no. 82 (Bequaert) (NHMB) [examined]. [Combination in Ponera (Hypoponera) : Santschi, 1938: 79; in Hypoponera : Bolton, 1995: 214.]

NOTE. The holotype of inaudax in mostly lost. Only the head remains on the mount, together with one leg. The mandibles and the anterior clypeal margin are embedded in glue and there is a hole in the vertex. Cephalic dimensions of the holotype are: HL 0.45, HW 0.36, HS 0.405, SL 0.28, CI 80, SI 78, SL/HL 0.62.

WORKER. Measurements: HL 0.40 – 0.46, HW 0.33 – 0.37, HS 0.365 – 0.410, SL 0.25 – 0.28, PrW 0.24 – 0.27, WL 0.54 – 0.60, HFL 0.24 – 0.29, PeNL 0.12 – 0.14, PeH 0.22 – 0.25, PeNW 0.16 – 0.19, PeS 0.167 – 0.190 (60 measured). Indices: CI 77 – 84, SI 74 – 82, PeNI 64 – 73, LPeI 50 – 59, DPeI 125 – 150.

Eyes absent. Apex of scape, when laid straight back from its insertion, conspicuously fails to reach the mid-point of the posterior margin in full-face view; SL/HL 0.60 – 0.66. Funiculus distinctly with 5 enlarging apical segments. Metanotal groove usually entirely absent from dorsum of mesosoma but in some a vestige of its former path may be visible. Mesonotal-mesopleural suture absent from side of mesosoma or at most represented by an almost effaced faint line. Propodeal declivity separated from sides by bluntly rounded curves or blunt angles; without an acute, raised, 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, usually obviously so; length of node just above anterior tubercle is noticeably greater than length of dorsum. Subpetiolar process conspicuously present in profile, somewhat variable in shape. Usually with a descending anterior face that terminates in a distinct ventral angle, behind which the outline slopes upwards. 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 are short and crowded, but conspicuous. 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.

This small, yellow species is closely related to coeca and both are sometimes recovered from single litter samples. It averages smaller than coeca and tends to possess shorter antennal scapes, as reflected in the key characters. Having said that, it seems probable that inaudax , as currently defined, contains more than one real species. There are subtle variations in the relative length of the scape, the shape of the petiole and its ventral process that defy analysis here. These may indicate that another species, intermediate between inaudax and coeca , should properly be recognised, or conversely, that intermediate specimens may eventually prove that the two are in fact extremes of a single species.

Material examined. Guinea: Camayenne (Silvestri). Ivory Coast: Tai For. (V. Mahnert); Tai For. (J. Piart); Bingerville (Mahnert & Perret). Ghana: Bunso (R. Belshaw); Sui For. Res. (R. Belshaw); Kade (R. Belshaw); Nkawkaw (R. Belshaw); Esunkawkaw (R. Belshaw); Southern Scarp For. Res. (R Belshaw); Atewa For. Res., nr Kibi (R. Belshaw). Nigeria: Ibadan, IITA (A. Russel-Smith); Ile Ife (J.T. Medler). Cameroun: Nkoemvon (D. Jackson); Mbalmayo (N. Stork); Korup N.P., Mundemba (B.L. Fisher); N’Kolo, Bondé For., Elogbatindi (B.L. Fisher). Gabon: La Makandé, For. des Abeilles (S. Lewis); Prov. Woleu-Ntem, Minvoul (B.L. Fisher); Prov. Ogooue-Maritime, Res. Monts Doudou, nr Doussala (B.L. Fisher); Res. Moukalaba, nr Doussala (B.L. Fisher); F.C. Mondah (B.L. Fisher); For. de Mondah, Cap Esterias (Bartolozzi & Taiti). Democratic Republic of Congo: Epulu (S.D. Torti); Yambuya (Bequaert). Kenya: Western Prov., Ekero (G. F i s c h e r).