GLASSY-WINGED SHARPSHOOTER (GWSS): Homalodisca coagulata (Say) Order - Hemiptera: Family - Cicadellidae

DISTRIBUTION: Southeastern United States and California.

DESCRIPTION: When eggs are first laid (Fig 2), they appear as a greenish blister on the leaf. The ♀ covers the leaf blister with a secretion that resembles white chalk. Shortly after the eggs hatch the leaves begin to turn brown. The dead leaf tissue remains as a permanent brown scar (Fig 3 - shown parasitized). Nymphs (Fig 4) look similar to adults except they are smaller, wingless, uniform olive-gray in color, and have prominent bulging eyes.

Adults (Fig 1) are about ½” long and are generally dark brown to black and covered with numerous ivory to yellowish spots. Their abdomens are whitish or yellow. Their heads are covered with ivory to yellowish spots. This distinguishes them from AZ’s native smoke-tree sharpshooters, whose heads are covered with light-colored lines, rather than spots.

HOSTS: Over 300 hosts are listed in CA, however the hosts of major concern are citrus, grapes, peach, almond and oleander.

DAMAGE: Large populations in hot weather may cause small plants to wilt. GWSS excrete copious amounts of liquid that can make leaves and fruit appear white washed when it dries. Cars are spotted if parked under heavily infested trees. The major concern is that GWSS spreads the disease-causing bacterium, Xylella fastidiosa, from one plant to another. This bacterium causes Pierce’s disease of grape (Fig 5), oleander leaf scorch, and almond leaf scorch in CA; and phony peach disease, plum leaf scald, and variegated citrus chlorosis in other states.

INSPECTION TIPS: Blending coloration and the tendency to hide by moving to the other side of twigs when approached makes GWSS inconspicuous. Leaves or fruit coated with whitish material may indicate feeding. The underside of leaves may be inspected for eggs. Large yellow sticky traps and sweep nets can also be used to detect this pest.

LIFE CYCLE: ♀’s lay eggs in masses of 10-12 in lower leaf surface of young, fully developed leaves. Nymphs hatch in 10-14 days and progress through 5 molts before becoming winged adults. In southern CA, there are two peaks of adult activity summer (1 st generation) and late fall/early winter (2 nd generation). Adults of the 2 nd generation spend the winter feeding in citrus and other evergreens and can move to deciduous plants in January and February, returning to the evergreens during cooler evening hours. These overwintering adults begin laying eggs in February but lay most of their eggs in late March and April.

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