Tetramorium barbigerum

Known only from the type collection from Okombahe in Namibia.

Identification
Mbanyana et al (2018) - Tetramorium barbigerum is easily distinguished from all species of the Tetramorium solidum group by its head shape, which is narrower in front of the eyes than behind. Morphologically, this species is similar to Tetramorium jordani and Tetramorium signatum in that they are all black in colour and lack erect hairs on the mesosoma, but the sculpture in Tetramorium signatum is much stronger developed compared to T. jordani and T. barbigerum. Tetramorium barbigerum and T. jordani have a feeble cephalic sculpture, fading out at the level of the eyes and replaced by a fine superficial punctation. These two species can be easily distinguished from each other by the lack of propodeal spines/teeth in T. jordani (PSLI 1–2) and the presence thereof in T. barbigerum (PSLI 7–8).

Distribution based on Regional Taxon Lists
Afrotropical Region: Namibia.

Nomenclature

 *  barbigerum. Tetramorium barbigerum Bolton, 1980: 243, figs. 19, 20, 25 (w.) NAMIBIA.

Worker
(workers N = 6) HL 1.214–1.266(1.244); HW 1.201–1.240 (1.223) SL 0.827–0.891 (0.857); EL 0.297–0.323 (0.308); PH 0.570–0.590 (0.583); PW 0.747–0.806 (0.775); WL 1.227–1.356 (1.294); PSL 0.089–0.098 (0.093); PTH 0.354–0.374 (0.363); PTL 0.354–0.384 (0.370); PTW 0.364–0.384 (0.375); PPH 0.517–0.568 (0.536); PPL 0.295–0.403 (0.362); PPW 0.443–0.472 (0.462); OI 24–26 (25); CI 95–101 (98); SI 67–72 (70); DMI 56–62 (60); LMI 42–49 (45); PSLI 7–8 (8); PeNI 46–50 (48); LPeI 95–108 (102) DPeI 108–132 (101); PpNI 58–62 (60); LPpI 57–76 (68); DPpI 117–153 (129); PPI 118–127 (123).

Type Material
Holotype. Namibia: worker, 10 mi. (16 km) W of Okombahe, 920 m a.s.l., 10 May 1958, R.E. Ross and R.E. Leech leg. (: CASTYPE13386). Paratypes. Namibia: 17 pinned workers, same data as holotype (CASC: CASENT0270787 to CASENT0270792); 3 pinned workers, same data as holotype.