Homoptera associated with the ants Crematogaster clariventris, Pheidole megacephala and Tetramorium aculeatum (Hymenoptera: Formicidae) on cocoa in Ghana

Abstract

AbstractPopulation densities of honeydew-producing Homoptera were assessed on mature upper-Amazon cocoa (Theobroma cacao) (Sterculiaceae) trees with combinations of the ants Crematogaster clariventris Mayr, Pheidole megacephala (Fabricius) and Tetramorium aculeatum (Mayr). Interactions were found between combinations of the three ant species and the abundance of Homoptera attended for honeydew. Crematogaster clariventris primarily attended Stictococcus sjostedti Cockerell (Stictococcidae), and less frequently Waxiella sp. nr zonata (Newstead) (Coccidae). Pheidole megacephala attended mealybugs, mainly Planococcoides njalensis (Laing), and Planococcus citri (Risso) (both Pseudococcidae). Tetramorium aculeatum was negatively associated with honeydew-producing Homoptera only when it was the sole dominant ant. Where T. aculeatum co-existed with either one, or both, of the other ant species, it had little influence on the abundance of the honeydew-producing Homoptera they attended, including the mealybug vectors of cocoa swollen shoot virus. Ant-attended Homoptera were more numerous on trees solely dominated by their attendant ants than on trees where two or all three ant species co-occurred. By contrast, the non-ant-attended psyllid Mesohomotoma tessmanni (Aulmann) was least common on trees with a single dominant ant species, and was most abundant on trees foraged by all three ant species.