Tetramorium nube

Identification
Bolton (1980) - Tetramorium nube, known only from the type-collection made in Sudan, is the most northerly known representative of this group. The dark colour, strongly sculptured mandibles and blunt body pilosity allies T. nube most closely with Tetramorium squaminode and Tetramorium platynode. The latter is quickly separated as in T. platynode the postpetiole is sculptured and very broad (about 0.76 x PW), and the ventral margin of the peduncle of the petiole is concave in profile. In contrast the postpetiole in T. nube is smooth and much narrower (about 0.66 x PW), and the ventral margin of the peduncle of the petiole is more or less straight in profile due to the presence of the laminar carina. T. squaminode separates from T. nube by having the dorsum of the petiole very narrow, in fact ending dorsally in a knife-edged crest, whereas in T. nube the scale is rounded above.

Distribution based on Regional Taxon Lists
Afrotropical Region: Sudan.

Nomenclature

 *  nube. Tetramorium squaminode subsp. nubis Weber, 1943c: 369, pl. 16, fig. 24 (w.) SUDAN. Raised to species: Bolton, 1980: 257.

Worker
Bolton (1980) - TL 3.2-3.4, HL 0.78-0.80, HW 0.72-0.75, CI 92-94, SL 0.56-0.57, SI 76-78, PW 0.56-0.58, AL 0.90-0.94 (2 measured).

Mandibles coarsely longitudinally striate. Anterior clypeal margin with a very shallow median impression. Frontal carinae widely separated and broadly sinuate, strongly developed and reaching back almost to the occipital margin. Antennal scrobes shallow but broad and conspicuous. Maximum diameter of eye 0.16-0.17, about 0.22-0.23 x HW. Dorsal alitrunk evenly rounded in profile, the metanotal groove not impressed. Propodeal spines long and acute, the metapleural lobes low and triangular. Petiole squamiform, in profile much higher than long, the peduncle of the petiole equipped ventrally with a broad laminar carina which is semitranslucent. Postpetiole in profile low and broadly rounded, without lobate ventral processes. In dorsal view both pedicel segements much broader than long, the postpetiole slightly broader than the petiole. Dorsum of head finely and quite densely irregularly longitudinally rugulose, with 10-12 rugulae between the frontal carinae at the level of the eyes. Cross-meshes absent except on the occiput where a few anastomoses are developed, but this area without a rugoreticulum. Ground-sculpture of head an inconspicuous punctulation, the spaces between the rugulae glossy. Dorsal alitrunk predominantly longitudinally rugulose but with a few cross-meshes, especially noticeable on the anterior pronotum. Petiole, postpetiole and gaster unsculptured. All dorsal surfaces of head and body with numerous stout blunted hairs but the scapes and tibiae only having short appressed or decumbent fine pubescence. Colour dark brown, the gaster slightly darker in shade than the head and alitrunk.

Type Material
Bolton (1980) - Syntype workers, SUDAN: Imatong Mts, Mt. Kineti, 9200 ft [2800 m], 28.vii.1939, no. 1355 (N. A. Weber) [examined].

References based on Global Ant Biodiversity Informatics

 * Weber N. A. 1943. The ants of the Imatong Mountains, Anglo-Egyptian Sudan. Bulletin of the Museum of Comparative Zoology 93: 263-389.
 * Yeo K., and A. Hormenyo. 2007. A Rapid Survey of Ants in Ajenjua Bepo and Mamang River Forest Reserves, Eastern Region of Ghana. Pp 27-29. In McCullough, J., P. Hoke, P. Naskrecki, and Y. Osei-Owusu (eds.). 2008. A Rapid Biological Assessment of the Ajenjua Bepo and Mamang River Forest Reserves, Ghana. RAP Bulletin of Biological Assessment 50. Conservation International, Arlington, VA, USA.