Terataner elegans Bernard

Bolton, B., 1981, A revision of six minor genera of Myrmicinae (Hymenoptera: Formicidae) in the Ethiopian zoogeographical region., Bulletin of the British Museum (Natural History) Entomology 43, pp. 245-307 : 292-293

Terataner elegans Bernard

(Figs 41,45,48)

Terataner elegans Bernard , 1952: 243. fig. 13 A. Holotype female, Guinea: Keoulenta (Lamotte) (MNHN, Paris) [examined].

Worker. TL 4.9 - 5.6, HL 1.18 - 1.40, HW 1.12 - 1.30, CI 92 - 97, SL 0.72 - 0.82, SI 58 - 65, PW 0.78 - 0.88, AL 1.50 - 1.76 (20 measured).

Mandibles weakly longitudinally rugulose to almost smooth, frequently with distinctive large pits close to the masticatory (apical) margin. Frontal carinae a pair of close-set straight, almost parallel ridges which fade out posteriorly between the level of the posterior margins of the eyes and the occiput. Antennal scrobes absent. Maximum diameter of eye 0.24 - 0.28, about 0.22 - 0.24 x HW. Pronotum in dorsal view marginate anteriorly and laterally, with strongly angulate or short-denticulate anterior corners. On sides of the pronotum margination runs from the anterodorsal to anteroventral angles. Mesonotum marginate laterally and propodeum also with lateral margination though here it is much less sharply defined than on the pronotum and in a few specimens is better described as bluntly angular. Lateral parts of promesonotal suture visible on dorsum but centrally it is usually completely effaced. Metanotal groove feebly indicated in profile by a shallow concavity or feeble indentation. Dorsum of pronotum about as long as broad, its width obviously less than the combined lengths of the pronotum and mesonotum. Propodeum unarmed. Petiole node low-triangular in profile, rising to a dorsal peak. In anterior view the dorsal margin of the node strongly emarginate medially, the portions on each side of the emargination appearing as a pair of stout tubercles or blunt teeth. Postpetiole in dorsal view flattened, in some the dorsum appearing shallowly longitudinally concave; the posterior margin of the postpetiolar dorsum broad and broadly rounded. Dorsum of head between frontal carinae with superficial but dense punctulate to granular ground-sculpture, and with a few very weak longitudinal rugulae which are commonly broken or interrupted. Sides of head above eyes with the same ground-sculpture and also with longitudinal rugulae which are usually somewhat stronger than those on the dorsum. Dorsal alitrunk finely and densely reticulate-punctulate and with feeble longitudinal rugulae, at least on the promesonotum. Postpetiole dorsally with a few stout conspicuous rugae. First gastral tergite shagreened to finely superficially punctulate, with fine costulae on the basal portion. Hairs very sparse on dorsal surfaces of head and body, present on mouthparts and gastral apex but otherwise the maximum complement seeming to be 3 - 4 pairs on the head along the lines of the frontal carinae, one pair on the pronotal corners, one pair on the propodeum, one pair on the posterior face of the petiole node and 1 - 2 pairs each on the postpetiole and first gastral tergite. These hairs appear to be lost easily by abrasion and completely hairless individuals are frequent. Scapes and tibiae without standing hairs of any description. Colour usually with head and gaster blackish brown to black, the alitrunk lighter brown or more usually reddish. Mandibles and clypeus usually lighter in colour than rest of head.

The four known species of the luteus-complex are confined to the forests of West and Central Africa. The complex is diagnosed by the short straight frontal carinae which fade out on the head behind the level of the eyes, fine sculpture, and sparse pilosity on the body; the tibiae lack standing hairs. Of the species thus defined two, elegans and luteus , have a broad flattened postpetiole, the posterior dorsal margin of which is broad and very broadly, evenly rounded. The other two species, piceus and velatus , have the posterior arch of the postpetiole narrow and narrowly rounded in dorsal view, compare Figs 40 and 41.

T, elegans and luteus are very closely related, being separated mainly on colour ( luteus is uniformly yellow), and on the dimensions of the pronotum as noted in the key. Apart from this the pronotum of luteus in dorsal view usually has the lateral margins more strongly convex than in elegans (Figs 48 and 49), though in smaller individuals this difference is often unapparent.

Material examined

Ghana: Tafo (C. Campbell); Tafo (B. Bolton); Kunso (D. Cross); Adeiso (D. Leston); Bunso (D. Leston); Sajimasi (D. Leston); Aburi (P. Room). Nigeria: Ife (B. Taylor).