Tetramorium viticola

A wet forest species. Based on where this ant has been found, it may be an arboreal nester. A collection from a rotten branch on the ground is the only ground-level collection of T. viticola. Other collections are from in and on dead above-ground twigs and samples from low vegetation.

Identification
Bolton (1980) - This distinctive species is closely related to Tetramorium quadridentatum and Tetramorium unicum, sharing their characteristic petiole node shape. It is separated from Tetramorium unicum by the fact that propodeal spines are reduced to minute teeth in that species. Characters separating T. viticolum from T. quadridentatum are tabulated under the latter name.

Distribution based on Regional Taxon Lists
Afrotropical Region: Central African Republic, Kenya, Sudan.

Nomenclature

 *  viticola. Tetramorium viticola Weber, 1943c: 372, pl. 16, fig. 31 (w.) SUDAN. See also: Bolton, 1980: 366.

Worker
Bolton (1980) - TL 3.7-3.9, HL 0.84-0.88, HW 0.70-0.72, CI 81-83, SL 0.60-0.62, SI 86-89, PW 0.56-0.58, AL 1.04-1.08 (4 measured).

Mandibles striate. Anterior clypeal margin entire, without a median notch or impression. Median clypeal carina strongly developed and forming a raised crest, especially on the anterior half; the median carina is flanked by at least one other sharp carina on each side, sometimes with two. Frontal carinae scarcely or not more strongly developed than the remaining cephalic sculpture, running back beyond the level of the eyes but irregular throughout their length and not following a more or less straight line. Behind the level of the eyes the frontal carinae quickly merge into the coarse sculpture. Eyes conspicuous, semicircular and domelike in full-face view, maximum diameter 0.19-0.20, about 0.27-0.29 x HW and with 10-12 ommatidia in the longest row. In full-face view the circumocular area of the head is seen to be somewhat concave. Propodeal spines in profile short stout and slightly upcurved along their length. Metapleural lobes as long as, or only slightly shorter than, the propodeal spines; acutely triangular, also upcurved and running roughly parallel with the propodeal spines. Petiole in profile with the anterior and dorsal faces combined in a single evenly convex curve, the dorsum shallowly convex and sloping upwards posteriorly to the sharp posterodorsal angle. Postpetiole also with combined anterior and dorsal faces and with a short free posterior face which may be overhung by the projecting posterodorsal angle. In dorsal view the petiole node as broad as long or slightly broader than long. Dorsum of head coarsely irregularly rugose, the rugae mainly longitudinal but meandering and with scattered cross-meshes which occur as far forward as the level of the anterior eye margins. Occipital region with a coarse rugoreticulum and reticulate-rugose sculpture also present on sides of head behind eyes and on sides between eyes and frontal carinae. Dorsal alitrunk coarsely and sharply rugose, forming a loose reticulum which is best developed on the pronotum. Groundsculpture of head a fine but fairly conspicuous superficial punctulation or shagreening, but this is much weaker or is suppressed on the alitrunk. Petiole and postpetiole sharply reticulate-rugose on all surfaces. First gastral tergite covered in minute dense punctulation which is very conspicuous; similar sculpture is also distinct on the first sternite. All dorsal surfaces of head and body with abundant pilosity. Colour uniform dark yellow or brownish yellow.

Type Material
Bolton (1980) - Syntype workers, SUDAN: Imatong Mts, W. slopes, 4900 ft [1490 ml], 3.viii.1939, no. 1409 (N. A. Weber) [examined].

References based on Global Ant Biodiversity Informatics

 * Bolton B. 1980. The ant tribe Tetramoriini (Hymenoptera: Formicidae). The genus Tetramorium Mayr in the Ethiopian zoogeographical region. Bulletin of the British Museum (Natural History). Entomology 40: 193-384.
 * Garcia F.H., Wiesel E. and Fischer G. 2013.The Ants of Kenya (Hymenoptera: Formicidae)Faunal Overview, First Species Checklist, Bibliography, Accounts for All Genera, and Discussion on Taxonomy and Zoogeography. Journal of East African Natural History, 101(2): 127-222
 * Ross S. R. P. J., F. Hita Garcia, G. Fischer, and M. K. Peters. 2018. Selective logging intensity in an East African rain forest predicts reductions in ant diversity. Biotropica 1-11.
 * Weber N. A. 1943. The ants of the Imatong Mountains, Anglo-Egyptian Sudan. Bulletin of the Museum of Comparative Zoology 93: 263-389.