Western grapeleaf skeletonizer

Definition

A species of day-flying moth (Lepidoptera: Zygaenidae) whose larvae feed on grape foliage, consuming the soft mesophyll between leaf veins and leaving a characteristic lace-like skeleton of vascular tissue. Native to the southwestern United States and northern Mexico, it is a significant vineyard pest in California and Arizona.

Etymology

Common name reflects its western North American distribution, host plant (grape), and the distinctive skeletonizing feeding damage caused by larvae

Example

Larvae of the Western grapeleaf skeletonizer feed gregariously on the undersides of grape leaves, producing transparent windows that expand and coalesce until only the network of veins remains; heavy infestations can defoliate vines and reduce fruit yield in commercial vineyards.

Synonyms

• Harrisina metallica

Related Terms

• skeletonization
• grape pest
• Zygaenidae
• leaf miner
• vineyard ecology
• Harrisina

Usage Notes

Distinguished from the eastern grapeleaf skeletonizer (Harrisina americana), which occurs in the southeastern United States; both species share similar larval habits and host associations. The specific epithet metallica refers to the metallic blue-black sheen of adult moths. Larvae are conspicuously yellow with transverse black bands and possess eversible, defensive glandular hairs (setae) that can irritate human skin.