Hypoponera fatiga Bolton & Fisher, 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 : 52-54

Hypoponera fatiga Bolton & Fisher sp. n.

(Figs 43 – 45)

WORKER (holotype in parentheses). Measurements: HL 0.46 – 0.53 (0.49), HW 0.36 – 0.40 (0.38), HS 0.410 – 0.450 (0.435), SL 0.28 – 0.34 (0.32), PrW 0.26 – 0.31 (0.29), WL 0.58 – 0.68 (0.64), HFL 0.28 – 0.34 (0.32), PeNL 0.12 – 0.14 (0.13), PeH 0.27 – 0.32 (0.30), PeNW 0.18 – 0.22 (0.22), PeS 0.195 – 0.227 (0.217) (30 measured). Indices: CI 73 – 80 (77), SI 78 – 87 (84), PeNI 67 – 78 (76), LPeI 39 – 44 (43), DPeI 155 – 180 (169).

Eyes absent. Median portion of clypeus with a raised median longitudinal ridge or crest. Apex of scape, when laid straight back from its insertion, distinctly fails to reach the midpoint of the posterior margin in full-face view; distance from apex of scape to midpoint ca 0.20 × SL, greater than the apical width of the scape; SL/HL 0.60 – 0.67. Reticulate-punctate sculpture on cephalic dorsum fine and dense, the punctures crowded, small and sharply defined. Lateroventral areas of head almost smooth, with widely separated, minute, superficial punctulae. Punctate sculpture on dorsum of pronotum about the same as on lateroventral surface of head. Metanotal groove entirely absent from dorsum of mesosoma. Sides of propodeal declivity weakly marginate. Petiole node in dorsal view transverse, the anterior and lateral surfaces distinctly convex, but not thickly D-shaped. Petiole node in profile slender and of moderate height, with the sides weakly convergent from just above tubercle to apex; dorsum very shallowly convex. Posterior surface of petiole node without radiating cuticular ribs above the peduncle. Subpetiolar process with a blunt ventral angle. Base of cinctus of second gastral tergite with short, fine, crowded cross-ribs. Disc of second gastral tergite microreticulate to superficially reticulate-punctate; without sharply incised widely separated punctures. Maximum width of first gastral tergite in dorsal view is less than the width of the second tergite at its midlength. Midline length of second gastral posttergite, from posterior margin of cinctus to apex, is slightly less than the maximum width of the segment. Suberect to erect setae on dorsum of first gastral tergite sparse and short, stubbly. Full adult colour light brown to brown.

Holotype worker (top specimen of two on pin), Ghana: Esunkawkaw, x.1992 (R. Belshaw) (BMNH). Paratypes. 22 workers and 3 dealate queens, with same data as holotype (BMNH, CASC, BBRC).

This small species is currently known from only a few forest leaf litter samples, but appears to be very widely distributed. The various populations are remarkably similar and show only slight differences in the ranges of dimensions, which at present are not considered as significant at species-rank. However, the Kenyan samples tend to have a petiole node that is somewhat more tapered dorsally, though the taxonomic significance of this is not currently apparent. The acquisition of samples from the vast territories that lie between these populations is essential, so that the situation can be assessed more accurately. In itself, the discovery of closely related populations as far apart as Ghana and Kenya, is not surprising, because the Kakamega Forest is the easternmost extension of the vast west and central African forest zone. That the species spans the entire zone is hinted at by the presence of a single specimen from Central African Republic. Critical measurements and indices of the main populations, for comparative purposes, are as follows.

Ghana workers (BMNH, CASC, BBRC). Measurements: HL 0.47 – 0.50, HW 0.36 – 0.38, HS 0.415 – 0.440, SL 0.28 – 0.32, PrW 0.28 – 0.30, PeNL 0.12 – 0.13, PeH 0.28 – 0.31, PeNW 0.20 – 0.22, PeS 0.200 – 0.220 (13 measured). Indices: CI 75 – 77, SI 78 – 86, PeNI 70 – 78, LPeI 41 – 43, DPeI 162 – 180.

Uganda workers ((KUIC). Measurements: HL 0.51 – 0.53, HW 0.38 – 0.40, HS 0.435 – 0.450, SL 0.31 – 0.33, PrW 0.30 – 0.31, PeNL 0.12, PeH 0.29 – 0.31, PeNW 0.20 – 0.21, PeS 0.203 – 0.213 (4 measured). Indices: CI 73 – 75, SI 82 – 83, PeNI 67 – 69, LPeI 39 – 41, DPeI 165 – 170.

Kenya workers (ZFMK). Measurements: HL 0.50 – 0.52, HW 0.38 – 0.40, HS 0.445 – 0.450, SL 0.33 – 0.34, PrW 0.28 – 0.30, PeNL 0.12 – 0.14, PeH 0.30 – 0.32, PeNW 0.20 – 0.22, PeS 0.210 – 0.227 (8 measured). Indices: CI 75 – 80, SI 84 – 87, PeNI 69 – 76, LPeI 39 – 44, DPeI 155 – 170.

Tanzania workers (KUIC). Measurements: HL 0.46 – 0.50, HW 0.36 – 0.38, HS 0.410 – 0.440, SL 0.28 – 0.31, PrW 0.27 – 0.29, PeNL 0.12, PeH 0.27 – 0.30, PeNW 0.18 – 0.20, PeS 0.195 – 0.207 (4 measured). Indices: CI 75 – 78, SI 78 – 83, PeNI 67 – 74, LPeI 40 – 44, DPeI 155 – 167.

See also the notes under defessa and juxta .

Non-paratypic material examined. Ghana: Poano (R. Belshaw); Kade (R. Belshaw); Tinte Bepo (R. Belshaw); Bobiri (R. Belshaw). Central African Republic: Dzanga-Ndoki, Lidjombo (B.L. Fisher). Uganda: Bushenyi Distr., Kalinzu For. (S. Yamane); Kalinzu N.P., Musanga For. (M. Kiyono). Kenya: Westen Prov., Kakamega For., Bunyale (G. F i s c h e r); Kakamega For., Malawa (G. F i s c h e r); Kakamega For., Kaimosi (G. F i s c h e r); Kakamega Distr., Buyangu Nat. Res., nr Salazar Circuit (Snelling & Espira); Kakamega Distr., Isecheno For. Res., Isecheno (R.R. Snelling); Isecheno For. Res., nr Kalunya Glade (R.R. Snelling). Ta nzan ia: Mahale Mts N.P., gallery forest (M. Kiyono).