Anochetus traegaordhi

In Cameroon and Congo this species was found to specialize on feeding on Nasutitermes termites, nesting in logs occupied by this prey (Schatz et al. 1999). In Saudi Arabia, Sharaf et al. (2017) found this species nesting in soil that was moist and rich in organic matter. A nest series was also found under a large Ficus tree (Moraceae) in Thi Ayn Archeological Village (Al Bahah Province) collected by digging. Some workers were found foraging in leaf litter at Wadi Aljora.

Identification
Sharaf et al. (2017) - Anochetus traegaordhi is a member of the Anochetus ghilianii-group as mentioned by Brown (1978). The A. ghilianii-group can be recognized by the medium or large body and eye sizes, the short cephalic longitudinal striations that fail to reach nuchal carina, the smooth and shining cephalic surface, and the thick, upright, compressed petiolar node as seen from profile.

Distribution based on Regional Taxon Lists
Afrotropical Region: Cameroun, Congo, Eritrea, Guinea, Ivory Coast, Kenya, Mozambique, Saudi Arabia, South Africa, Sudan, Yemen, Zimbabwe.

Biology
Collingwood (1985) - Scattered accounts include a Zimbabwe collection from a sandy soil nest (Arnold 1946), a nest discovered under a tree in Sudan (Viehmeyer 1923) and two foragers found foraging on the ground in bushy scrub.

Schatz et al. (1999): Workers of Anochetus traegordhi are specialized in the capture of Nasutitermes sp. termites. Both species were found to live in the same logs fallen on the ground of the African tropical rain forest. A. traegordhi has a very marked preference for workers over termite soldiers. The purpose of the capture of soldiers, rather than true predation, was to allow the ants easier access to termite workers. During the predatory sequence, termite workers were approached from behind, then seized and stung on the gaster, while soldiers were attacked head on and stung on the thorax. When originating from a different nest-site log than their predator ant, termites were detected from a greater distance and even workers were attacked more cautiously. Only 33.3% of these termite workers were retrieved versus 75% of the attacked same-site termite workers. We have demonstrated that hunting workers can recognize the nature of the prey caste (workers versus termite soldiers) and the origin of the termite colony (i.e. sharing or not the log where the ants were nesting), supporting the hypothesis that hunting ants can learn the colony odor of their prey. This, in addition to the nest-site selection of A. traegordhi in logs occupied by Nasutitermes can be considered as a first step in termitolesty.

Sharaf et al. (2017) - This species was collected nesting in soil that was moist and rich in organic matter. A nest series was found also under a large Ficus tree (Moraceae) in Thi Ayn Archeological Village (Al Bahah Province) collected by digging. Some workers were found foraging in leaf litter at Wadi Aljora.

Nomenclature

 *  traegaordhi. Anochetus traegaordhi Mayr, 1904b: 2 (w.) SUDAN. Senior synonym of silvaticus: Brown, 1964d: 215; of angusticornis, gracilicornis (and its junior synonym sudanicus): Brown, 1978c: 559 (see also p. 598).
 * gracilicornis. Anochetus gracilicornis Viehmeyer, 1923: 87, fig. 1 (w.) SUDAN. Senior synonym of sudanicus: Brown, 1964d: 215. Junior synonym of traegaordhi: Brown, 1978c: 559.
 * sudanicus. Anochetus sudanicus Weber, 1942a: 47, fig. 7 (w.) SUDAN. Junior synonym of gracilicornis: Brown, 1964d: 215.
 * angusticornis. Anochetus angusticornis Arnold, 1946: 56 (w.q.) ZIMBABWE. Junior synonym of traegaordhi: Brown, 1978c: 559.
 * silvaticus. Anochetus silvaticus Bernard, 1953b: 212, fig. 5 (w.q.) GUINEA. Junior synonym of traegaordhi: Brown, 1964d: 215.

Worker
Sharaf et al. (2017) - EL 0.25–0.30, HL 1.50–1.75, HW 1.25–1.50, MDL 0.90–1.05, ML 2.00–2.25, PNH 0.65–0.95, PNL 0.30–0.40, PNW 0.25–0.40, PW 0.60–0.80, SL 1.45–1.60, TL 5.35–7.50; Indices: CI 77–93, EI 17–22, MDI 57–63, PNI 157–317, SI 100–116 (n=9). The specimens used for measurements were recent collections from the KSA.

Head: Posterior margin of head strongly concave; eyes of moderate size (EI 17–22); scapes short, fail to reach posterior margin of head. Mesosoma: Promesonotum feebly convex in profile; metanotal groove impressed; propodeal dorsum about 2.5 3 longer than declivity; propodeal outline obtusely angulate. Petiole: In profile, anterior face broadly concave, posterior face feebly convex; petiolar node narrowly rounded. Sculpture: Cephalic surface smooth and shining except for fine striations between frontal carinae, running posteriorly and outwards to level of posterior margin of eyes; mesosoma faintly and irregularly rugulose; mesopleuron smooth; petiole and gaster smooth and shining. Pilosity: Cephalic surface without hairs or pubescence, anterior clypeal margin with few simple hairs, mandibles and antennae with appressed pubescence, mesosoma with scattered short hairs (hair length 0.08), gaster with scattered hairs. Color: Uniform yellow, gastral tergites yellow with brown tint.

Type Material
Sharaf et al. (2017) - (w.) Sudan. Afrotropical. Type not located.