Submitted to: Biological Control
Publication Type: Review article
Publication Acceptance Date: 5/25/2009
Publication Date: 6/2/2009
Publication URL: dx.doi.org/10.1016/j.biocontrol.2009.05.014
Citation: Biddinger, D.J., Weber, D.C. Weber, and Hull, L.A. 2009. Coccinellidae as predators of mites: Stethorini in biological control. Biological Control. 51: 268-283. http://dx.doi.org/10.1016/j.biocontrol.2009.05.014. Interpretive Summary:
Technical Abstract: The Stethorini are unique among the Coccinellidae in specializing on mites (principally Tetranychidae) as prey. Consisting of 90 species in two genera, Stethorus and Parasthethorus, the tribe is practically cosmopolitan, and found in diverse habitats, including many agricultural systems, as well as ornamental plantings, grasslands, forests, and heathlands. Tetranychid mite outbreaks became common in agriculture only after widespread use of broadspectrum insecticides after World War II. Stethorini were initially appreciated only for their ability to suppress severe outbreaks of tetranychid populations. However, research on their prey searching behaviors reveals that Stethorini use visual and olfactory stimuli to locate small mite colonies in patchy distributions, and can be very effective in regulating their prey at low densities. Key to the use of coccinellids in conservation biological control programs is the provision of overwintering habitats and refuges from pesticides in and near cropland. When these conditions are fulfilled, Stethorini often play important roles in maintaining suppression of tetranychid populations; examples of successful biological mite control include apple orchards in Pennsylvania, citrus in Asia, and the unintended disruption of a tetranychid-based biological control program for gorse, an invasive woody weed. The systematics and taxonomy of this group is challenging with many cryptic species, and molecular diagnostic tools are sorely needed. How best to utilize their mite-suppressive potential in diverse settings requires better knowledge of their requirements including utilization of alternative foods, refuges for dormancy and from nonselective pesticides, and host-finding mechanisms.