Hypoponera coeca (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 : 34-36

Hypoponera coeca (Santschi)

(Figs 19 – 21)

Ponera coeca Santschi , 1914b: 322, fig. 9. Syntype worker and queen, CAMEROUN: Victoria (F. Silvestri) (NHMB) [not seen, presumed lost]. [Combination in Ponera (Hypoponera) : Santschi, 1938: 79; in Hypoponera : Bolton, 1995: 213.] (See note.)

Ponera myrmicariae Wasmann , 1918: 144. Syntype workers, CAMEROUN: Kamerunburg, Soppo, 730 m., xii.1912, “ bei Myrmicaria eumenoides ” (von Rothkirch) (NHMM) [examined]. Syn. n. [Combination in Ponera (Hypoponera) : Santschi, 1938: 79; in Hypoponera : Bolton, 1995: 215.]

NOTE. Neither of the original syntypes seems to have survived. A pair of specimens in NHMB, one queen and one headless worker, identified as coeca by Santschi and possessing red “type” rectangles, are mislabelled as they are from Guinea: Camayenne (Silvestri) and hence are not part of the type-series. The worker body is very small and resembles inaudax . In the original description Santschi (1914b) compares coeca with gleadowi and ergatandria . The first of these is now a junior synonym of ragusai and the second a junior synonym of punctatissima . Both of these species always have small but conspicuous eyes and a strongly developed metanotal groove across the dorsal mesosoma; they are not closely related to coeca which, in Santschi’s own description, is referred to as “aveugle” and with the metanotal groove “ presque effacée.” Santschi’s original description and drawings of coeca match a species that is common and widespread in west and central Africa, and is conspecific with the syntypes of Wasmann's myrmicariae .

WORKER. Measurements: HL 0.47 – 0.52, HW 0.37 – 0.42, HS 0.415 – 0.465, SL 0.30 – 0.35, PrW 0.26 – 0.32, WL 0.61 – 0.70, HFL 0.29 – 0.35, PeNL 0.13 – 0.17, PeH 0.25 – 0.31, PeNW 0.18 – 0.22, PeS 0.187 – 0.233 (75 measured). Indices: CI 77 – 84, SI 80 – 89, PeNI 63 – 77, LPeI 50 – 57, DPeI 125 – 150.

Eyes usually absent, extremely rarely a tiny eye-spot present (see below). In full-face view apex of scape, when laid straight back from its insertion, fails to reach the midpoint of the posterior margin; SL/HL 0.65 – 0.71. 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 but always with a descending anterior face that terminates in a distinct ventral angle. Behind the angle the outline may slope evenly upwards posteriorly, but more usually there is a short, more steeply ascending portion of the margin immediately behind the angle; intermediate forms are known. 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.

As with its very close relatives camerunensis and inaudax , the present concept of coeca may conceal more than one real species, but these currently defy analysis. Different samples show subtle variations in the shape and size of the petiole node. Some have the node slightly longer, higher or broader than others, some have the petiole dorsum more broadly convex than in others, some have the anterior and posterior surfaces more obviously convergent dorsally than in others and there is variation in the shape of the ventral process. In addition, although the vast majority of specimens completely lack eyes, extremely rarely a tiny eye-spot is discernible that at its greatest development is a single ommatidium, small and only partially pigmented. They are best developed in a short series in CASC from Gabon (Res. Monts Doudou, 19.iii.2000, numbers 2250, 2256 and 2258). Because they otherwise fit the above description, they have been retained within coeca for the time being.

Within the limits of the description above, coeca is a small, yellow species that is very widespread and quite common in samples of leaf litter and rotten wood across wide areas of sub-Saharan Africa.

Material examined. Guinea: Nimba (Lamotte). Ivory Coast: Tai For. (V. M a h n e r t); Nzi Noua (W. L. B r o w n); Iringou (F. K r e l l); Abidjan, Banco For. Res. (I. Löbl); Banco Nat. Pk (I. Löbl); Banco (Delamare); Man (Mahnert & Perret); Agboville, Yapo For., nr Yapo-Gare (I. Löbl); Sassandra, Monogaga (I. Löbl). Ghana: Bobiri (R. Belshaw); Poano (R. Belshaw); Esunkawkaw (R. Belshaw); Sagymasi (R. Belshaw); Atewa For. Res., Kibi (R. Belshaw); Mt Atewa (D. Leston); Tafo (R. Belshaw); Tafo (D. Leston); Mampong (P. R o o m); Legon (D. Leston). To g o: Palimé, Klouto For. (Vi t). Nigeria: Gambari (B. Bolton). Cameroun: Mbalmayo (N. Stork); Nkoemvon (D. Jackson); Korup (D. Jackson); Korup N.P., Mundemba (B.L. Fisher); Mvini (A. Dejean); Yaoundé (A. Dejean); Prov. Sud, P.N. Campo (B.L. Fisher); Res. de Faune de Campo, Ebodjé (B.L. Fisher); Res. Campo, Massif des Mamelles (B.L. Fisher); N’Kolo, Bondé For., Elogbatindi (B.L. Fisher); Prov. Sud-Ouest, Bimbia For., Limbe (B.L. Fisher); Mtn Cameroon, Mapanja (B.L. Fisher); Kamerunberg, Soppo (von Rothkirch). Gabon: Makokou (I. Lieberburg); 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). Central African Republic: Dzanga-Ndoki, Mabéa Bai (B.L. Fisher); Dzanga Ndoki, Lidjombo (B.L. Fisher); Res. Dzanga-Sangha, Bayanga (B.L. Fisher). Congo: Res. de Tchimpounga, Pointe Noire surr. Lac Foni (Bartolozzi & Bambi). Uganda: Bushenyi Dist., Kalinzu For. (S. Yamane). Kenya: Western Prov., Kakamega For., Lugari (S. Maurer); Kakamega For., Isecheno(R.R. Snelling); Isecheno, Nat. Res. (R.R. Snelling); Isecheno For. Res., Kalunya Glade (R.R. Snelling); Malindi(Pardi & Ugolini). Ta nz a n ia: Tanga Reg., Kilindi For. Res. (Hawkes, Makwati & Mtana); Morogoro Reg., Mkungwe For. Res. (Hawkes, Bhoke & Richard); Pwani Reg., Kichi Hills For. Res. (Hawkes, Mlacha & Ninga). Angola: Gabela (P.M. Hammond). South Africa: Gauteng Prov., Ezemvelo Nat. Res. (Hawkes & Clark).