Ants (Hymenoptera : Formicidae) associated with the leafhopper Dalbulus quinquenotatus (Homoptera : Cicadellidae) on gamagrasses in Mexico

Field studies in Jalisco, Mexico, show that the deltocephaline leafhopper Dalbulus quinquenotatus DeLong & Nault is consistently associated with attendant ants on its gamagrass ( Tripsacum spp.) host plants. Eighteen species of ants from four subfamilies were found tending this leafhopper, indicating the ants are facultative members of this mutualistic relationship. The two most commonly associated ant species were Brachymyrmex obscurior Forel and Solenopsis geminata (F.). In a detailed field survey of 195 Tripsacum plants at 13 sites, all 121 plants with colonies of D. quinquenotatus (nymphs and adults) had tending ants. None of these plants was colonized by other Dalbulus species. Of the 61 plants from which D. quinquenotatus and ants were absent, 43 had D. elimatus (Ball), D. gelbus DeLong, or D. tripsacoides DeLong & Nault adults or adults and nymphs present. The role that ants play in the biology of D. quinquenotatus is discussed.