Tetramorium sericeiventre Emery

Type location Eritrea (Emery, 1877b: 370, worker; not from Ethiopia as in Bolton, 1987) collected at Sciotel by O Beccari; junior synonyms arenarium (Santschi, 1918b: 126, worker; Santschi, 1937g: 82, male) from Tunisia, hortensis (Atopula hortensis, Bernard, 1948: 173, illustrated; all forms; synonymy by Bolton, 1976: 363) from Libya; bipartita (Santschi, 1918b: 126, worker) from Kenya, blochmannii (Forel, 1887: 384, worker; Forel, 1910f: 19, queen & male) from Madagascar, cinnamomeum (Santschi, 1918b: 124, worker; Arnold, 1926: 249, worker) and vividum (Santschi, 1926b: 242, worker) from Mozambique, continentis (Forel, 1910e: 426, worker; Forel, 1913b: 319, queen; Arnold, 1917: 279, male) and femoratum (Emery, 1895h: 37, worker) from South Africa, debile (Forel, 1894b: 80, worker) and neuvillei (Forel, 1907c: 135, worker) from Ethiopia, gamaii (Santschi, 1918b: 128, worker) and vascoi (Santschi, 1918b: 128, worker & queen) from Zimbabwe, hori (Santschi, 1918b: 125, worker) from Sudan, jasonis (in Santschi, 1918b: 127, worker & queen; also from Dimbroko, by Le Moult, in Wheeler, 1922) from Ivory Coast, Jacqueville, by Lohier; munda (Santschi, 1918b: 127) from Guinea, Kakoulima, F. Silvestri; and nigriventre (Stitz, 1910: 144, worker; but type location, as a variety of blochmanni, given as Togo, at Misahöhe by Smend, in Stitz, 1910, and Wheeler, 1922) from Cameroun; material of unavailable names colluta (Santschi, 1918b: 129, worker) and transversa (Santschi, 1918b: 128) from South Africa, defricta (Santschi, 1918b: 129, worker), georgei (Santschi, 1918b: 131, all forms) and gladiator (Santschi, 1928f: 206, worker) from Zimbabwe, evidens (Santschi, 1928f: 206, worker) from Zaïre, kenyense (Santschi, 1933b: 106, worker & queen) from Kenya, and platonis (Santschi, 1918b: 130, worker) from Botswana; all forms described (see Bolton, 1995) .

Emery's (1877b) description is at . Arnold (1917: 294) gave a translation, with femoratum; this is at . Forel's (1894b) description of debile is at . Emery's (1895h) description of femoratum is at . Forel's (1907c) description of neuvillei is at . Forel's (1910e) description of continentis is at . Stitz's (1910) description of nigriventre is at . Arnold's (1917) translation of continentis is at Santschi's (1918b) description of varieties are at , , and . Arnold (1926) gave translations of several varieties (including most of the Santschi, 1918b, descriptions), these are at , . and . Santschi's (1926b) description of vividum is at . Santschi's (1928f) descriptions of evidens and gladiator are at 17. Santschi's (1933b) description of kenyensis is at 18. Santschi's (1937g) description of the arenarium male is at 19. Bolton's modern description (1980) is at 20 and 21- TL 3.3-4.4 mm, in Bolton (1980: 332), illustrated, head, clypeus and mandibles, alitrunk and pedicel profile, pedicel dorsum.

Santschi (1910c) noted inversa as being larger, TL 3.5-4 mm, and more robust than the type, with heavier sculpturation but a less silky appearance to the gaster. Bernard's (1948) description of "Atopula hortensis" is at This also contains ecological and biological observations.

Nigeria specimens (Taylor, 1980a: 51). WORKER. TL 3.92 mm, HL 0.93, HW 0.78, SL 0.90, PW 0.59
Head, alitrunk and pedicel densely and finely punctate with overlying rugoreticulation; rugae longitudinal especially on the head and dorsal alitrunk. Gaster with extremely fine puncturation. Erect hairs stout, sparse and moderately long. Propodeal spines relatively long, narrow and triangular, pointing slightly upwards. Petiole node with a sloping anterior face merging through a rounded obtuse angle into the dorsum with a slightly convex profile; posterior face near vertical. Colour orange-brown, except the gaster which is very dark near black.

Basically a savannah species but found nesting in insolated ground in the forest zone. Found foraging below the soil surface. Bolton (1980) lists numerous West African findings.

In Nigeria, including the Cocoa Research Institute of Nigeria, Idi Ayunre (B. Bolton; B. Taylor), IITA (B. R. Critchley), Ibadan and Nsukka (W.H. Gotwald & R. Schaefer), Mokwa (C. Longhurst), Ile-Ife and Gusau (J.T. Medler), Bauchi (Walker). Wheeler (1922) had nigriventre from Ibadan (F. Silvestri), plus the type form from Old Calabar (Bates, in Forel, 1911) and Ibadan (F. Silvestri).

In Ghana, Room (1971) found it in leaf litter under cocoa and on open ground at the Mampong Cemetery site. That was listed by Bolton (1980), plus many other findings - Asesewa and CRIG (B. Bolton), Dahwhenya (C. A. Collingwood), Krobo (A.H. Strickland), Besuso, Larteh and Legon (D. Leston).

Lévieux & Diomande (1978) in their description of the activity of Pachycondyla sennaarensis at Ferkéssédougou, Ivory Coast, mentioned that Tetramorium sericeiventre was an active predator on other ants, and that twice they had seen it transporting Pachycondyla sennaarensis workers to its nest.

Other West African records are Liberia, at Harbel (W.M. Mann); Senegal, near Dakar (W.L. Brown); Ivory Coast, at ORSTOM (W.L. Brown); and Cameroun, at Nkolbisson (no details). Wheeler (1922) had the type form and nigriventre also from Guinea (Conakry and Kakoulima, F. Silvestri); plus the type form from Sierra Leone; and arenarium from Senegal (at Fello, by Claveau). The nests of continentis in Zaïre were described as "small nests in sand" some 50 cm deep with crater-like entrances, the crater rims being entirely of sand particles, with no food debris; the ants were busy even in a fairly bright midday sun (see illustration left and "click").

The photomontage of the holotype from Eritrea is collated from http://www.antweb.org/specimen.do?name=casent0102073

The photomontage is of a specimen from Gabon, Pongara National Park, Pointe Ngombé; 17.vii.2006; under beach edge trees, collected by Yves Braet.
This seems close in general configuration and colour to the type form. The head width is not much less than the head length. The overall sculpturation on the head, alitrunk and pedicel is distinct but weak. The mandibles are only weakly sculptured, appearing almost smooth from some angles. The gaster is relatively pale and more brown than black.

Other images can be seen in the folder at -

The photomontage is of a specimen collected in Cameroun - 30 km east of Poli at a Sudan-Guinea savannah location (McKey Wolbachia project) - Cameroon 126, 15 June 2001; a single specimen in a sample of numerous Monomorium bicolor - a species with a very similar colouration. This seems a match for the variety nigriventre, as described from Cameroun by Stitz (1910), i.e. more brightly coloured and more coarsely sculptured than the type form

Other images can be seen in the folder at -

Photomontage of a specimen from Sudan, collected at Adock, South Sudan Province, by Awatif Omer, 2006, Sudan 14-1. This seems close to the description given by Santschi (1918b) for n. var hori, from Khartoum; with the rugulose petiole and dark colour. The characters also match those given by Bernard (1948) for "Atopula hortensis", particularly distinct are the sparse stouter erect hairs and the relatively slender overall shape; with noticeably longer legs (the hindfemur is as long as the alitrunk dorsum) and longer propodeal spines. Given more specimens, I suspect that hori could be argued as a clearly distinct species, junior synonym hortensis; being a species distributed across the Sahara or Sahel. Other images can be seen in the folder at -

Photomontage of a specimen from Ghana, collected by S Sky Stephens, 2006. Other images can be seen in the folder at -

Other images from the Central African Republic can be seen in the folder at -

Bernard (1952) described it as a common African insect, from the Tunisian steppes to Transvaal, with at least 8 races and 30 varieties. In Guinea, several workers collected from Mt. Nimba - from Kéoulenta savanna, and Mount Tô Ravine I - differed from known forms by their darker red-brown colour, stronger reticulation (masking the longitudinal striation) and a head vertex which was more deeply impressed. He felt that it may have represented a simple summation of montane development, as a queen taken at Nimba more clearly matched the type form.

The photomontage here is of a slender form from Gabon, Pongara National Park; Savannah at Pointe Denis; 16.vii.2006; 24h pitfall traps at edge of a forest grove; collectors L Volait & L V Guieu; that seems a close match to Bernard's (1948) illustration of hortensis. Other images can be seen in the folders at - , and .