| Cataulacus kohli|
Nothing is known about the biology of Cataulacus kohli.
A member of the huberi group. A quite distinctive medium-sized species. The strongly flattened hind femora, form of sculpturation and lack of dorsally situated hairs coupled with a complete absence of denticles render this species quite easily recognizable. (Bolton 1974)
Keys including this Species
Mostly confined to the rain forest areas of West and Central Africa, but does occur in East African forests (Bolton 1974).
Distribution based on Regional Taxon Lists
Distribution based on specimens
Much of the information concerning the biology of Cataulacus species is anecdotal and fragmentary. Arnold (1917) wrote a succinct general overview of Cataulacus biology that still remains quite informative. Arnold reports "all the species of this genus are tree-ants, usually forming medium sized nests in hollow twigs and stems, or more rarely, under the bark. They are timid and slow-moving insects, often feigning death or dropping rapidly to the ground when disturbed. As Bingham has remarked in connection with this genus (Fauna Brit. India, Formicidae), these ants have the habit of wandering over the trunks of trees and the leaves in what appears to be a very aimless and languid manner. I have occasionally seen them breaking open the earthen tunnels constructed by termites over the trunks of trees and attack the inmates."
Bolton (1974) expands upon this earlier account - "All known Cataulacus species are arboreal or subarboreal nesters and they predominantly forage on the trees and shrubs in which the nests are situated. Very few appear to come down to ground level but in West Africa the small species Cataulacus pygmaeus and Cataulacus brevisetosus may be found foraging in leaf litter or crossing the ground to ascend a tree other than the one in which the nest is situated. The nests themselves are usually constructed in small hollow twigs or stems by the smaller species and in rotten branches or rotted portions of the tree trunk by the larger species. This is rather a generalization as some small species are known which nest in and under rotten bark (e.g. Cataulacus vorticus) and undoubtedly some of the larger forms will eventually be found inhabiting relatively small cavities in plants.
Various species of the genus in Africa are known to inhabit a variety of galls, acacias and bushes as well as large trees. Numerous species have been found nesting in, and have therefore been often collected from, cocoa in Africa. Some of these species are Cataulacus guineensis, Cataulacus pygmaeus, Cataulacus mocquerysi, Cataulacus egenus, Cataulacus vorticus, Cataulacus brevisetosus, Cataulacus kohli and Cataulacus theobromicola. Feeding habits in the genus are mostly unknown but the present author has noted C. guineensis tending aphids and small coccids.
On the plants ants of the genus Cataulacus often occur together with Oecophylla or species of Crematogaster, and appear to be mostly tolerated (at least they are not evicted) by the majority of these forms. Their defence against attackers of these genera lies primarily in their armoured exterior, but their ultimate escape reaction is to curl up and release their grip on the plant, falling to the ground and thus making their escape. The decision to remain immobile and present an armoured surface or to drop from the plant appears to depend upon the size or persistence of the aggressor; larger attackers usually precipitate the latter reaction, but it has also been noted as a result of persistent and unwanted attention by a series of workers of a small Crematogaster species.
The majority of species are forest-dwelling forms, with relatively few adapted to savannah or veldt conditions. Those which do, however, occur in these zones tend to be very successful in their chosen habitat and often possess a wide distribution. A few species are apparently able to exist in any region of Africa providing the basic essentials of nesting-site and food supply are met with, but on the whole the fauna may be divided into forest and non-forest forms."
Some species have nests that can be protected by a single worker's head, as its shape matches the nest entrance and forms an effective plug.
It has more recently been discovered that some species of Cataulacus are efficient gliders (Cataulacus erinaceus, Cataulacus guineensis, Cataulacus mocquerysi and Cataulacus tardus). Workers exhibit directed movement while in freefall that allows them to glide back to regain a hold on the same tree trunk. (Yanoviak et al. 2005, 2007, 2008)
The following information is derived from Barry Bolton's New General Catalogue, a catalogue of the world's ants.
- kohli. Cataulacus kohli Mayr, 1895: 127, fig. 2 (w.) SIERRA LEONE. Senior synonym of brazzavillensis, foveolatus, latipes: Bolton, 1974a: 22.
- brazzavillensis. Cataulacus kohli st. brazzavillensis Santschi, 1910c: 389, fig. 15 (w.m.) CONGO. Junior synonym of kohli: Bolton, 1974a: 22.
- foveolatus. Cataulacus foveolatus Stitz, 1910: 140 (w.) EQUATORIAL GUINEA. Junior synonym of kohli: Bolton, 1974a: 22.
- latipes. Cataulacus latipes Menozzi, 1933a: 106, fig. 4 (w.) UGANDA. Junior synonym of kohli: Bolton, 1974a: 22.
Unless otherwise noted the text for the remainder of this section is reported from the publication that includes the original description.
Bolton (1974) - TL 5.1 – 7.1, HL 1.24 – 1.74, HW 1.64 – 2.28, CI 126 -132, EL 0.48 – 0.60, OI 26 - 29, IOD 1.22 – 1.90, SL 0.74 – 1.04, SI 41 - 45, PW 1.52 – 2.14, AL 1.40 – 2.10, MTL 0.84 – 1.30. (5 measured).
Sculpturation of dorsum of head capsule usually finely granulose with scattered, superimposed shallow pits or foveolae. Laterally, close to and behind the eyes are some fine rugulations which tend to curve towards the midline of the occipital margin. Rarely, and usually in smaller workers, these rugulae are also present in the centre of the dorsum. Alitrunk, especially the mesonotum and propodeum, finely and densely reticulate-punctate with fine, scattered longitudinal rugulae. Pronotal dorsum more variably sculptured, the rugulae may even run transversely on the anterior portion. Petiole transversely rugose; the anterior face of the postpetiole longitudinally rugose. First gastral tergite finely and densely reticulate-punctate, overlaid by dense, very fine, virtually parallel rugulations which are arranged in a broadly circular or oval pattern around the sclerite or are convergent on the midline anteriorly.
Dorsal surfaces of head, alitrunk and gaster without hairs. Hairs are abundant upon the legs and a row of very short, blunt hairs projects from the lateral margins of the head behind the eyes. Lateral pronotal margins without such a projecting series of short hairs.
Bolton (1974) :
Holotype worker, SIERRA LEONE: N'Gamie River, Samlia Falls (location of type not known).
Cataulacus kohli st. brazzavillensis Syntype workers, male, CONGO (BRAZZAVILLE): Brazzaville (A. Weiss) (NM, Basle) [examined].
Cataulacus foveolatus Holotype worker, EQUATORIAL GUINEA: Uelleburg (Tessmann) (MNHU, Berlin) [examined].
Cataulacus latipes Syntype workers, UGANDA: Entebbe (E. Bayon) (IE, Bologna).
- Bolton, B. 1974a. A revision of the Palaeotropical arboreal ant genus Cataulacus F. Smith (Hymenoptera: Formicidae). Bull. Br. Mus. (Nat. Hist.) Entomol. 30:1-105. PDF (page 22, Senior synonym of brazzavillensis, foveolatus and latipes)
- Mayr, G. 1895. Afrikanische Formiciden. Ann. K-K. Naturhist. Mus. Wien 10: 124-154 (page 127, fig. 2 worker described)