Ophthalmopone berthoudi

Distribution based on Regional Taxon Lists
Afrotropical Region: Kenya, Namibia, Zimbabwe.

Biology
This queenless ant hunts termites exclusively, and foragers do not cooperate (Peeters & Crewe 1987). Colonies are polydomous, distributed over 2-7 nests separated by distances varying from 30cm to 75m. There is frequent relocation of workers and brood among nests (186±151 workers, range 20-840, n=34 nests excavated).





Castes
Male behaviour in this queenless ant was studied in the field (Peeters & Crewe 1986). During several weeks of the year, a few males (1-8) flew off daily from each of a number of nests examined. Copulation with young workers occurs inside nests after foreign males succeed to enter.

In 34 nests excavated from Mkuze (northern Zululand), 1-108 workers had sperm in their spermathecae and ovaries with yolky oocytes (549 workers dissected; Peeters & Crewe 1985). However a majority of these mated workers lacked one or more mature oocytes ready to be laid. Nests collected before the onset of mating season had few gamergates and their fecundity was higher.

Twelve nests were excavated near Hoedspruit (Limpopo province) and a total of 619 workers were dissected. The number of mated workers per nest ranged from 1 to 36, and ovarian activity varied according to how many were present in a nest (Sledge et al. 1996). In nests with high proportions of mated workers, they exhibited diverse behaviours (mainly brood-related) and in some cases could not be distinguished behaviourally from virgin workers. In nests with low proportions of gamergates, these were more fecund and did not participate in colony labour. The behavioural profile of gamergates is therefore linked to their reproductive physiology (Sledge et al. 1999).

Unlike other queenless ants where dominance interactions regulate reproductive activity among workers, there is no aggression in O. berthoudi, and mesh experiments showed that contact pheromones underlie regulation (Sledge et al. 2001).

Nomenclature

 *  berthoudi. Ophthalmopone berthoudi Forel, 1890b: cxiii (w.) SOUTH AFRICA. Forel, 1894b: 76 (m.); Wheeler, G.C. & Wheeler, J. 1971b: 1203 (l.). Combination in Pachycondyla: Brown, in Bolton, 1995b: 303; in Ophthalmopone: Schmidt & Shattuck, 2014: 124. Current subspecies: nominal plus pubescens. See also: Arnold, 1915: 50; Peeters & Crewe, 1985: 29; Peeters & Crewe, 1987: 201.