DeJean, A., McKey, D., Gibernau, M., & Belin, M. 2000 The arboreal ant mosaic in a Cameroonian rainforest (Hymenoptera: Formicidae).. Sociobiology 35(3): 403-423.
Notes: The ant mosaic of the canopy of a Cameroonian rainforest was studied by directly sampling 167 large trees and 20 vines reaching the canopy level using a dirigible and the "canopy raft", the "canopy sled", and, when necessary, the single rope technique. Although plant species diversity was high (trees: 63 species from 29 families; vines: 9 species from 7 families), our results show an ant assemblage characterized by high abundance but low diversity (28 ant species in total). We recorded only four "dominant" ant species (i.e., species with populous colonies that build their own nests, exhibit strong territoriality, and have mutually exclusive territories distributed in a mosaic pattern). The most frequent species, Crematogaster depressa, occupied 87.4% of the trees and 85% of the vines, and its colonies reached several million workers. Other dominants were recorded at low frequencies (Crematogaster sp.1: 1.8% of the trees; Oecophylla longinoda: 6.0%; Tetramorium aculeatum: on one vine). Among the nine ant species tolerated on the territories of Cr. depressa (i.e., "non-dominant" species with smaller colonies), the workers of three species shared their trails with Cr. depressa, while Camponotus brutus, with colonies sometimes able to occupy the entire crown of a tree, rather had the status of "subdominant". Extrafloral nectaries (EFN) played a role in ant species distribution. The large ecological success of Cr. depressa is probably due to its ability to nest on trees with or without EFN. O. longinoda, which rarely tolerated non-dominant ant species, was significantly more frequently recorded on trees without EFN. While dominant ants depended principally on attended homopterans (Coccidae and Stictococcidae; globally: 300,000 to 700,000 individuals per tree), nondominant species depended primarily on EFN. Scale species mentioned include Coccus sp., Couturierina piptadeniastri, Houardia sp., Parasaissetia nairobica. Saissetia sp., Udinia farquharsoni, Stictococcus intermedius, Ceroplastes sp. and Aspidiotini sp.