Common Name: Broad mite
Scientific name: Polyphagotarsonemus latus (Banks)
Description: Adult mites are microscopic (100 to 300 microns). These mites are very similar to cyclamen mites, Phytonemus pallidus (Banks), but can be separated by the lack of tubercles on cyclamen mite eggs and by the structure of the hind legs of the males.
Life cycle: Mites can be identified only with proper magnification. Eggs are clear, oval and marked with characteristic rows of white tubercles that appear gem-like under proper lighting. Immatures resemble adults, but smaller. Adult males and females have four pairs of legs, with two pair toward the front of the body and two near the rear. The middle of the body may be constricted to look waist-like. Males are shorter, broader and have longer hind legs than females. The life cycle takes from 4 to 10 days, depending on temperature.
Habitat and food source(s): Mouthparts are piercing and sucking, similar to spider mites. Broad mites infest a wide range of host plants, including pepper, cotton, citrus, tomatoes, potatoes, beans, Gerber daisy, dahlias, zinnias and chrysanthemums.
Pest status: Broad mites are a particular problem on greenhouse grown nursery crops during the winter months. The mites are found on the undersides of leaves and in cupped young foliage and flower buds. Affected leaves turn bronze in color, may thicken, become brittle and appear cupped or otherwise deformed as they emerge. Occasionally, the growing point of the plant is killed. Feeding causes deformed buds and newly-expanded leaves on host plants. Harmless to man and animals.
Literature: Riley 1992. Reviewed Burke 3/1996.