Brown Citrus Aphid, Toxoptera citricida (Kirkaldy)
Brown citrus aphid (BCA) is not currently found in California. Populations of BCA have distributed themselves throughout Florida and Hawaii and are gradually moving northward through Mexico. Thus, it could arrive in California at any time. This species of aphid feeds only on citrus and close relatives of citrus. It directly damages the trees by curling and twisting new flush, but more importantly, it is a very efficient vector of citrus tristeza virus (CTV). Wherever the aphid has arrived around the world, the severity of citrus tristeza virus has increased. Currently, the San Joaquin Valley of California has a very low incidence of CTV and symptoms of the virus isolates are fairly mild if resistant rootstock is used. Establishment of the brown citrus aphid is likely to change that situation for the worse. The purpose of this publication is to educate citrus and nursery personnel about brown citrus aphid.
Interactive Key for Differentiating Brown Citrus Aphid from Aphids that Infest California Citrus Please be patient in waiting for the program to load and close and use your 'back' button to return to this page after you have exited the teaching module.
This interactive web site is designed to familiarize you with the distribution, biology, and damage of the brown citrus aphid and teach you how to recognize the BCA compared to other aphids that commonly infest citrus. If you suspect that you have found such an aphid, preserve winged specimens in ethyl alcohol and take them to your local county agricultural commissioners office for identification.