Tetramorium dichroum

Tetramorium dichroum has been recorded from grassland with trees, and also in Karoo vegetation. This species nests in the soil and feeds on seeds.

Identification
Mbanyana et al (2018) - In the Tetramorium solidum group, there are five species with abundant hairs covering the dorsal surfaces of the whole body, namely, Tetramorium rothschildi, Tetramorium peringueyi, Tetramorium dichroum, Tetramorium margueriteae and Tetramorium brigitteae. Tetramorium rothschildi is easily separated from other species by having branched hairs. Tetramorium dichroum can be easily distinguished from T. peringueyi and T. margueriteae by the absence of erect hairs on the antennal scapes. Tetramorium dichroum and T. brigitteae can be distinguished on the basis of the spine length: in T. dichroum spines are long and acute (PSLI 10–16), whereas T. brigitteae has very short propodeal teeth (PSLI 6).

Distribution
South Africa (Eastern Cape Province, southern parts of the Free State, Northern Cape and Western Cape Provinces) and Zambia.

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

Habitat
Known from Drakensberg Montane Grasslands, Kalahari Xeric Savanna, Montane Fynbos and Renosterveld, Nama Karoo, Succulent Karoo, Zambezian and Mopane Woodlands.

Nomenclature

 *  dichroum. Tetramorium solidum st. dichroum Santschi, 1932a: 388 (w.) SOUTH AFRICA. Subspecies of peringueyi: Prins, 1973: 11. Raised to species: Bolton, 1980: 245.

Worker
Mbanyana et al (2018) - (N = 11) HL 0.934–1.023 (0.987); HW 0.944–1.072 (1.003); SL 0.659–0.747 (0.703); EL 0.216–0.246 (0.237); PH 0.393–0.521 (0.451); PW 0.590–0.669 (0.638); WL 0.924–1.121 (1.015); PSL 0.098–0.157 (0.136); PTH 0.315–0.364 (0.341); PTL 0.275–0.354 (0.325); PTW 0.315–0.374 (0.343); PPH 0.315–0.491 (0.438); PPL 0.246–0.285 (0.267); PPW 0.382–0.457 (0.415); OI 23–25 (24); CI 100–105 (102); SI 66–73 (70); DMI 59–70 (63); LMI 39–52 (45); PSLI 10–16 (14); PeNI 50–57 (54); LPeI 85–100 (95); DPeI 99–114 (106); PpNI 61–70 (65); LPpI 50–80 (62); DPpI 144–186 (156); PPI 115–128 (121).

Type Material
Mbanyana et al (2018) - Syntypes South Africa: 3 pinned workers, Northern Cape, Kimberley, 1924, Power leg. (: CASENT0915004; : SAM-ENT-0011758).

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.
 * IZIKO South Africa Museum Collection
 * Mbanyana N. 2013. Taxonomy, phylogeny and biogeography of seed-harvesting ants in the Tetramorium solidum-group (Hymenoptera: Formicidae). Masters of Science in the Department of Botany and Zoology at Stellenbosch University 115 pages.
 * Prins A. J. 1973. African Formicidae (Hymenoptera) in the South African Museum. Description of four new species and notes on Tetramorium Mayr. Annals of the South African Museum 62: 1-40.
 * Santschi F. 1932. Formicides sud-africains. Pp. 381-392 in: Jeannel, R. (ed.) 1932. Société Entomologique de France. Livre du centenaire. Paris: Société Entomologique de France, xii + 729 pp.