Tetraponera tessmanni

Identification
A member of the Tetraponera allaborans species-group.

Distribution based on Regional Taxon Lists
Afrotropical Region: Cameroon, Central African Republic, Democratic Republic of Congo, Equatorial Guinea.

Biology
Tetraponera tessmanni is the only inhabitant of mature Vitex thyrsiflora lianas, providing effective defense against herbivores. The association between V. thyrsiflora and T. tessmanni is unusual. Pseudomyrmecine plant-ants often prune vegetation contacting their host plant. This behavior functions in part to protect against invasion of the host by ecologically dominant ants. In contrast, T. tessmanni does not prune because its liana that depends on contacts with many other plants. Several traits of V. thyrsiflora and T. tessmanni combine to make the colonization of host plants by potential competitors very difficult. These include behavioral and morphological filters restricting entrance into the plant and exploitation of the resources it can supply; modifications in plant anatomy that enables T. tessmanni workers to carry out all activities, except leaf patrolling, within a single private nesting space where food resources are offered by the plant; and polygyny permitting the colony to monopolize a large, rapidly growing and long-lived territory (Djiéto-Lordon et al. 2005).

Castes
Wheeler (1922b: 108) noted a considerable variation in queen size, including ergatoid and brachypterous (subapterous) forms, as well as dealate individuals. Djiéto-Lordon et al. (2005) - One queen morph has fully functional wings. We observed that claustrally founded colonies were without exception founded by dealate queens of this morph. The other morph has wings reduced to functionless nubs, and a narrower thorax. Tetraponera tessmanni is the only pseudomyrmecine known to show such queen dimorphism (P. Ward, pers. comm.). Established colonies included numerous apparently functional egg-laying queens of both morphs.

Nomenclature

 *  tessmanni. Sima tessmanni Stitz, 1910: 131, fig. 2 (w.) EQUATORIAL GUINEA. Santschi, 1919h: 84 (q.); Wheeler, W.M. 1922a: 110 (m.); Wheeler, W.M. 1918c: 304 (l.); Wheeler, G.C. & Wheeler, J. 1956: 391 (l.). Combination in Tetraponera: Wheeler, W.M. 1918c: 303; in Viticicola: Wheeler, W.M. 1919i: 130; Wheeler, W.M. 1922a: 109; in Sima (Tetraponera): Emery, 1921f: 28; in Tetraponera: Ward, 1990: 489. Senior synonym of castanea: Brown, 1950e: 248.
 * castanea. Viticicola tessmanni var. castanea Wheeler, W.M. 1922a: 112 (w.q.) DEMOCRATIC REPUBLIC OF CONGO. Junior synonym of tessmanni: Brown, 1950e: 248.

References based on Global Ant Biodiversity Informatics

 * Baroni Urbani C. 1977. Katalog der Typen von Formicidae (Hymenoptera) der Sammlung des Naturhistorischen Museums Basel (2. Teil). Mitt. Entomol. Ges. Basel (n.s.) 27: 61-102.
 * IZIKO South Africa Museum Collection
 * Stitz H. 1910. Westafrikanische Ameisen. I. Mitteilungen aus dem Zoologischen Museum in Berlin 5: 125-151.