Red or scarlet lily beetles (Lilioceris lilii) are pests that induces panic in lily growers because they can cause a lot of damage rapidly. Affected genus include Cardiocrinum, Fritillaria, Lilium and Nomocharis.
Lily beetle is native to Europe and Asia; it was imported to the UK becoming established in the late 1930's and has since slowly spread throughout the whole country. It has also become established in North America. Systemic insecticides like imidacloprid (Provado) give effective control.
Click here to see PBS list postings about lily beetle.
Photographs by David Pilling. Photo 5 shows dropping encrusted larvae munching away at a leaf.