Partners in biological control of cocoa pests: Mutualism betweenDolichoderus thoracicus(Hymenoptera: Formicidae) andCataenococcus hispidus(Hemiptera: Pseudococcidae)

Abstract

The observed mutualistic relationship between the black cocoa ant Dolichoderus thoracicus (Smith) and the mealybug Cataenococcus hispidus (Morrison) was examined. The importance of C. hispidus to D. thoracicus as a food source was investigated by giving D. thoracicus access to C. hispidus only, to C. hispidus and other food sources, and denying access to any obvious food sources. Dolichoderus thoracicus was seen to depend on C. hispidus alone as a source of food over an eight-week period of observation without showing ill effects. The role of D. thoracicus in spreading C. hispidus was studied in an experiment consisting of combinations of D. thoracicus and C. hispidus exclusion. It was shown that D. thoracicus was responsible for carrying C. hispidus across a ‘mealybug excluder’. Data on the frequency and duration of transport of C. hispidus by D. thoracicus were obtained by direct observation for a total of 90 h over 17 days. Both adults and nymphs of C. hispidus were carried by D. thoracicus with its mandibles in a brief and erratic manner, in the general direction of the trail. Such transportation is nevertheless considered to be important in view of the large number of individuals of D. thoracicus moving along a trail. The close mutualistic relationship between D. thoracicus and C. hispidus reiterates the necessity to manipulate both organisms for control of cocoa pests.

Effects of selective logging on the arboreal ants of a Bornean rainforest

“…Furthermore, trophobiotic species such as Dolichoderus thoracicus was highly abundant and frequent in the logged forests. The species is known to occur in large numbers in cocoa farms with trophobiotic partners (Pseudococcidae) (Ho & Khoo 1997). Although we have no ecological information for Crematogaster sp.…”

Novel Approaches for the Management of Mealybug Pests

“…vovae (Nasonov), which occurs on cypress trees (Cupressus spp.) grown in windbreaks, serves as an alternative host for natural enemies of mealybug pests in surrounding citrus orchards and cocoa plantations (Cox 1989;Ho and Khoo 1997;Franco et al 2004b). Mealybugs have also provided food for humans; the biblical manna, one of the food sources consumed by the Israelites during their wandering in the wilderness of Sinai, is believed to have been the honeydew excretion of the manna mealybug, Trabutina mannipara (Hemprich and Ehrenberg in Ehrenberg) (Ben-Dov 2006;Miller and Kosztarab 1979).…”

Ecological stoichiometry of ants in a New World rain forest

“…Some myrmicine and pseudomyrmecine leaf-foragers (cephalotine tribe group and Tetraponera) are also regularly associated with bacteria, these residing in or near the hindgut and presumed to recycle waste N (Caetano and Cruz-Landim 1985;Van Borm et al 2002). Although, upgrading of nonessential to essential AAs by hemipteran microsymbionts may not translate into more balanced AA profiles in honeydew (Sandstrom and Moran 2001), at least some hemipteran-tending ants harvest trophobionts or their hemolymph (e.g., Ho and Khoo 1997;Delabie 2001), and could be less N-deprived than are leaf-foragers.…”