MS Student University of Florida Homestead, Florida
We report several phoretic mites associated with ambrosia beetles for the first time. Ambrosia beetles spend most of their life inside galleries built on host trees. They use the xylem as a substrate for farming symbiotic fungi. Some of these symbionts are plant pathogens that infect avocado (Persea americana) trees in South Florida, such as Raffaelea lauricola and Fusarium sp. A few other organisms inhabit ambrosia beetle galleries, including phoretic mites. Little is known about the ecology of phoretic mites and their potential application in pest management. A survey was conducted in eight avocado orchards and swampbay (Persea palustris) stands in Florida. Ambrosia beetles were captured in flight using modified Lindgren traps, as they emerged from infested logs placed in emergence chambers, and were also physically excavated from infested logs. Nine mite species in five families were collected from nine beetle hosts, including Asca sp. (Ascidae), Proctolaelaps bickleyi and Proctolaelaps sp. (Melicharidae), Acarothorectescurculionium, Elattoma sp., Brazilopsisfloridensis, and Pediculaster sp. (Pygmephoridae), Tarsonemus sp. (Tarsonemidae), and Histiogaster arborsignis (Acaridae). The mite family Pygmephoridae was the most abundant group. Acarothorectescurculionium and Elattoma sp. were the most common phoretic mite species, and B. floridensis is a new mite species found in this study. The phoretic associations were not specific to a particular ambrosia beetle species. The cryptic living habits of ambrosia beetles make their management challenging. Future studies will evaluate the potential of phoretic mites to be incorporated into innovative IPM practices for managing ambrosia beetles and other wood-boring pests.
