Tetramorium clunum

This is a ground-nesting species, sometimes with part of the nest underneath rocks. It has been recorded nesting in deep soils. Nothing is known about its feeding behavior but presumably feeds on seeds, as this is recorded for other species of this group. Yellow pan trap, pitfall trap and turning the stones are the methods that have been used to collect this species.

Identification
Mbanyana et al. (2013) - In the T. solidum-group there are only three species with short, broad, much flattened and strongly appressed glittering silvery hairs covering the body, namely, Tetramorium setuliferum, Tetramorium clunum and Tetramorium galoasanum. Tetramorium galoasanum is distinguished from the other two species by its long, dense, overlapping strap-like hairs, whereas in the other two species these hairs are sparse and spaced out. Tetramorium clunum is separated from T. setuliferum by the following characters: (1) first gastral tergite does not overhang the tergosternal suture in profile; (2) first gastral tergite is sculptured throughout whereas in T. setuliferum only the base is sculptured; (3) dorsum of head behind clypeus with at least one pair of erect hairs, whereas T. setuliferum lacks elongate erect hairs on the dorsum of head; and (4) tergum of postpetiole without lateral alar prominences; whereas T. setuliferum has these present.

Distribution
Tetramorium clunum has been recorded from South Africa (Eastern Cape, Western Cape, and Northern Cape) and Namibia.

Distribution based on Regional Taxon Lists
Afrotropical Region: Namibia, South Africa.

Habitat
Collected from Nama Karoo, Succulent Karoo and the Namib Desert.

Nomenclature

 *  clunum. Tetramorium setuliferum st. cluna Forel, 1913j: 218 (w.) SOUTH AFRICA. Raised to species: Bolton, 1980: 244.

Worker
Bolton (1980) - TL 3-9-4-6, HL 1:00-1:18, HW 0-96-1-14, CI 94-98, SL 0-68-0-80, SI 65-72, PW 0-60-0-70, AL 0-95-1-16 (15 measured).

Mandibles coarsely longitudinally rugulose. Anterior clypeal margin with a quite shallow but extensive emargination so that the border is concave. Frontal carinae rapidly fading out behind the well developed — frontal lobes, not or only just reaching the level of the extreme anterior margins of the eyes. Antennal scrobes absent. Eyes of moderate size, maximum diameter 0-22-0-26, about 0:22-0:24 x HW. Outline of dorsal alitrunk unbroken in profile, the metanotal groove not impressed. Propodeal spines acute, strongly developed. Metapleural lobes broadly rounded and plate-like. Petiole in profile strongly nodiform, in dorsal view broader than long and distinctly broader behind than in front. In a few specimens the anterolateral corners of the node in dorsal view are slightly exaggerated and the anterior face has a tendency to form a slight concavity medially. Sternal portion of postpetiole in profile directed downwards into a distinctive blunt process, one on each side of the segment. If viewed from below the space between these two processes is flat or feebly concave and the processes are strongly prominent. In dorsal view the postpetiole roughly transversely oval, broader than the petiole. With the gaster in profile the basal portion of the first sternite not overhung and hidden by a thick downcurved projection of the tergum, the tergo-sternal suture being visible to the base of the gaster. Entire dorsum of head very finely and very densely longitudinally costulate, the small spaces between the costulae punctulate. Dorsal alitrunk basically similarly sculptured but the costulae much less strongly developed than on the head, nearly effaced in some so that only the punctulate sculpture remains. Dorsal surfaces of petiole and postpetiole densely punctulate and dull. First gastral tergite minutely longitudinally striolate from base to apex; in some the striolation not well developed and the gaster appearing shagreened and dull. Dorsal surfaces of head and body with sparse short, flattened, strongly appressed glittering silvery hairs. These are most easily observed on the occipital region of the head, the pronotum, pedicel segments and base of the first tergite; they are very strongly appressed and most appear to be sunk in small indentations in the cuticle. Similar but not so strongly appressed glitterin; hairs are present on the legs and antennal scapes. Elongate hairs are present only on the clypeus, dorsum the head (1-2 pairs only), the gastral segments behind the first and the first sternite. Psammophore present on ventral surface of head. Colour dull reddish brown or brown

Mbanyana et al. (2018) - (N = 11) HL 0.885–1.062 (0.958); HW 0.919–1.090 (0.991); SL 0.688–0.757 (0.723); EL 0.207–0.266 (0.239); PH 0.482–0.570 (0.544); PW 0.570–0.669 (0.609); WL 0.922–1.023 (0.963); PSL 0.157–0.177 (0.168); PTH 0.285–0.344 (0.307); PTL 0.295–0.340 (0.315); PTW 0.305–0.381 (0.325); PPH 0.413–0.530 (0.461); PPL 0.187–0.246 (0.207); PPW 0.374–0.472 (0.401); OI 22–27 (24); CI 101–105 (103); SI 69–76 (73); DMI 61–67 (63); LMI 51–62 (57); PSLI 15–19 (18); PeNI 49–57 (53); LPeI 97–113 (103) DPeI 92–112 (103); PpNI 63–71 (66); LPpI 40–58 (45); DPpI 152–218 (195); PPI 117–127 (124).

Type Material
Mbanyana et al (2018) - Syntypes. South Africa: workers, Eastern Cape, Willowmore, Dec. 1912, H. Brauns leg. (: CASENT0901182; : CASENT0909155).

References based on Global Ant Biodiversity Informatics

 * Forel A. 1913. Ameisen aus Rhodesia, Kapland usw. (Hym.) gesammelt von Herrn G. Arnold, Dr. H. Brauns und Anderen. Deutsche Entomologische Zeitschrift 1913(Suppl.): 203-225.
 * IZIKO South Africa Museum Collection
 * Mbanyana N., F. Hita Garcia, H. G. Robertson, and J. J. Le Roux. 2018. A taxonomic revision of seed harvester ants of the Tetramorium solidum group (Hymenoptera: Formicidae) in southern Africa. European Journal of Taxonomy 454: 1-59.
 * Wheeler W. M. 1922. Ants of the American Museum Congo expedition. A contribution to the myrmecology of Africa. VIII. A synonymic list of the ants of the Ethiopian region. Bulletin of the American Museum of Natural History 45: 711-1004