Tetramorium nefassitense

Identification
A member of the Tetramorium simillimum species group.

Bolton (1980) - This small species is apparently closest related to Tetramorium ghindanum, which has similar strong gastral sculpture. The two are, however, easily separated as in T. ghindanum projecting hairs are present on the sides of the head behind the eyes and the eyes themselves are smaller.

Distribution based on Regional Taxon Lists
Afrotropical Region: Eritrea, Ethiopia.

Nomenclature

 *  nefassitense. Tetramorium caespitum var. nefassitensis Forel, 1910c: 260 (w.) ETHIOPIA. Raised to species: Bolton, 1980: 315.

Worker
Bolton (1980) - TL 2.0-2.1, HL 0.56-0.58, HW 0.50-0.51, CI 88-89, SL 0.37-0.38, SI 74, PW 0.32-0.34, AL 0.56-0.58 (2 measured).

Mandibles longitudinally striate; anterior clypeal margin entire, the median clypeal carina strongly developed and distinctive. Eyes well developed, maximum diameter c. 0.13, about 0.25-0.26 x HW, with 9 ommatidia in longest row. Frontal carinae very feeble, discernible to level of eye but no more strongly developed than other longitudinal cephalic sculpture. Behind level of eyes frontal carinae absent as such, absolutely indistinguishable from other cephalic sculpture. Antennal scrobes absent. Sides of head behind eyes more or less parallel, slightly convergent towards the occipital corners, the latter rounded. In full-face view the sides behind the eyes without projecting hairs between the eyes and the stout hair at the occipital corner. Alitrunk in profile with only the feeblest trace of indentation at the metanotum, the propodeal dorsum sloping towards a pair of minute triangular denticles. Metapleural lobes broadly triangular and much more massively developed than the propodeal denticles. Petiole in profile with the tergal portion of the node higher than long, the anterior and posterior faces almost parallel, very slightly convergent dorsally. Petiole node in dorsal view much broader than long. Dorsum of head finely but quite strongly evenly longitudinally rugulose, the spaces between them with a weak ground-sculpture so that the surface is shining. Dorsal alitrunk finely reticulate-punctulate with a few very faint longitudinal rugulae on the pronotum. Dorsal surfaces of petiole and postpetiole densely reticulate-punctulate, granular in appearance. Basal one-third of first gastral tergite as strongly punctulate as postpetiole. Standing hairs present on all dorsal surfaces of head and body, short, stout and blunt, such hairs absent from the appendages. Colour mid to dark brown, the appendages pale brown.

Type Material
Bolton (1980) - Syntype workers, Ethiopia: Nefassit (K. Escherich) [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.
 * Forel A. 1910. Ameisen aus der Kolonie Erythräa. Gesammelt von Prof. Dr. K. Escherich (nebst einigen in West-Abessinien von Herrn A. Ilg gesammelten Ameisen). Zoologische Jahrbücher. Abteilung für Systematik, Geographie und Biologie der Tiere 29: 243-274.
 * Madl M. 2019. Notes on the ant fauna of Eritrea (Insecta: Hymenoptera: Formicidae): type specimens deposited in the Natural History Museum Vienna (Austria) and a preliminary checklist. Ann. Naturhist. Mus. Wien, B 121: 9-18.