Tetramorium dolichosum

Identification
Bolton (1980) - This slender species with very long scapes is most closely related to Tetramorium perlongum, and its separation from that species is discussed there. These two species together form a compact pair within the setigerum-group characterized by their narrow heads (CI 75 or less), long scapes (SI > 150), short frontal carinae and low, rounded metapleural lobes.

Distribution based on Regional Taxon Lists
Afrotropical Region: Democratic Republic of Congo.

Nomenclature

 *  dolichosum. Tetramorium dolichosum Bolton, 1980: 277 (w.) DEMOCRATIC REPUBLIC OF CONGO.

Worker
Holotype: TL 4.6, HL 1.06, HW 0.79, CI 75, SL 1.22, SI 154, PW 0.60, AL 1.26. Paratypes (2 measured): TL 4.3—4.7, HL 1.04-1.08, HW 0.77-0.81, CI 74-75, SL 1.22-1.31, SI 158-162, PW 0.56-0.60, AL 1.22-1.30. Maximum diameter of eye 0.22-0.24, about 0.28-0.30 x HW.

Mandibles longitudinally striate. Anterior clypeal margin entire, without a median impression. Median clypeal carina running the length of the clypeus. Frontal carinae short, running back to a level just behind the posterior margins of the eyes. The carinae strongly developed throughout their length, close together (their maximum separation only about 0.38 x HW), terminating abruptly in a strong, rugoreticulum. Antennal scapes very long, SI > 150; antennal scrobes absent. Maximum diameter of eye 0.22, about 0.28 x HW. In full-face view the occipital margin evenly concave, bordered by a raised rim or flange; head elongate and narrow, CI above. Masticatory margin of mandible armed with three teeth followed by a series of 6 denticles. With the alitrunk in profile the promesonotum evenly convex, sloping posteriorly to a weakly impressed metanotal groove. Propodeal dorsum approximately flat but with a very low tumulus just posterior to the metanotal groove. Propodeal spines elongate, narrow and acute. Metapleural lobes low and rounded. Petiole in profile with a long peduncle, the node with rounded antero- and posterodorsal angles and a gently convex dorsum. Postpetiole evenly convex. Dorsum of head coarsely and densely reticulatepunctate and with conspicuous rugular sculpture which forms a strong reticulum behind the level of the eyes. Dorsum and sides of alitrunk reticulate-punctate, the former also with disorganized but strong rugulae. Petiole, postpetiole and base of first gastral segment finely and densely reticulate-punctulate. All dorsal surfaces of head and body with numerous strong hairs which are blunt apically. Appendages without such hairs, only with fine appressed pubescence. Colour uniform dark brown.

Paratypes: As holotype but one paratype having 3 teeth plus 7 denticles on the mandible as opposed to 3+6 in holotype and the other paratype.

Type Material
Holotype worker, Zaire (‘B. Congo’ on data label): 14 miles (23 km] NW. of Mutshatsha, 30.i.1958, 1200 m (E. S. Ross & R. E. Leech) . Paratypes. Two workers with same data as holotype (CASC; ).