Callejas-Chavero A., Martínez-Hernández D. G., Vargas-Mendoza C. F., Flores-Martínez A., Herbivory in Myrtillocactus geometrizans (Cactaceae): Do Parasitoids Provide Indirect Defense or a Direct Advantage?, Plants, 2023, 12(1):47, doi: 10.3390/plants12010047
The Hidalgo field study examines interactions between the cactus, the soft scale Toumeyella martinezae, its parasitoid Mexidalgus toumeyellus and the ant Liometopum apiculatum. Scale presence was associated with weaker stem growth, fewer buds and flowers, and greater sooty-mould cover. Excluding ants increased the incidence of parasitism in scales. The results show how ants protecting a herbivore reduce the indirect benefit that its natural enemy provides to the plant.