Coreopsis Leaf Beetle
Photographer: JC Jones
Adult Description: The coreopsis leaf beetle (Phaedon desotonis) is a member of the family Chrysomelidae consisting of the leaf beetles receiving their name sake from their herbivorous diet. There are eight known species from the genus Phaedon in the United States. All eight species share a characteristic convex oblong body, metallic elytra, and are 3-5 mm long. The coreopsis leaf beetle has a metallic green pronotum, a purple to brown metallic body, and small punctures that are barely noticeable relative to other Phaedon spp.
Host Plant: Coreopsis spp. and Bidens aristosa (Asteraceae)
Ecological Threat: The coreopsis leaf beetle is capable of causing severe damage to plants in the larval stage because of constant feeding on leaves. When larval densities are high, plants can be damaged to the point of being eaten down to the ground. In Florida, the protected official state wildflower has been a recorded host increasing the pest damage potential of the coreopsis leaf beetle.
Biology: Larval coreopsis leaf beetles can be seen in May feeding on host plants. Adults emerge in mid-June and feed for a few weeks before copulating and dropping eggs near the base of the host plant in a protected area. The eggs will remain dormant until the following spring when larvae emerge and begin a new generation.
History: The native location of the coreopsis leaf beetle is unknown, but most likely it is native to the southeastern United States. It was mistaken for a similar beetle Phaedon viridis until 1983 when it was described by Balsbaugh. The coreopsis leaf beetle is similar to other beetles indigenous to the United States, but had been rarely collected until recently indicating that its range is expanding rapidly likely due to host plant expansion.
U.S. Habitat: The coreopsis leaf beetle is able to survive in a wide range of habitats with it's preferred host plants present.
Native Origin: Unknown
U.S. Present: AL, AR, GA, FL, OK, TX
There are currently no management plans in place for the coreopsis leaf beetle. If you believe that coreopsis beetles are established in your area please contact local parks and wildlife officials. You may also send and email to TISI@shsu.edu to report a suspected establishment within the state of Texas.
Balsbaugh, E. U., Jr. 1983. A taxonomic revision of the genus Phaedon north of Mexico (Coleoptera: Chrysomelidae). North Dakota Insects Schafer-Post Series 15, 73 p.
Braman, S.K., Pendley, A., and W. Corley. 2002. Plant susceptibility to and seasonal occurrence of Phaedon desotonis Balsbaugh, a leaf beetle attacking Coreopsis. Journal of Environmental Horticulture 20: 220-223.
Wheeler, A. G., Jr., and E. R. Hoebeke. 2001. Phaedon desotonis Balsbaugh (Coleoptera: Chrysomelidae): New distribution records, first host-plant associations, and seasonality of a seldom-collected beetle of rock-outcrop communities. Proceedings of the Entomological Society of Washington 103: 826-831.