Extension > Garden > Diagnose a problem > What insect is this? > Garden Pests > Caterpillars, maggots, grubs, and similar immature insects - 1/4 inch - 1/2 inch long > Bristly roseslug
Bristly roseslug
Cladius difformis
Jeff Hahn, University of Minnesota Extension
Description: Up to 1/2 inch long.
Where/When: Feeds on the surface of rose leaves between the veins. Older larvae chew holes. Active from mid May through early September.
Significance: Feeding produces windowpane or lacey appearance to leaves, eventually causing damaged areas to turn brown. Entire parts of the leaves are also eaten. Feeding affects the appearance of roses but rarely impacts their health.
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