Scarlet lily beetle (Lilioceris lilii)

Common Names: Lily leaf beetle

Description: Native to Europe and Asia and first discovered in Montreal, Canada in the 1940s. Said to have been introduced to North America through imported plant bulbs in 1943.

Identification: 6-9 mm (1/4 - 3/8 in.) long, with relatively long legs and antennae. Elytra is bright scarlet red and shiny while underside, legs, eyes, antennae and head are all black. Large eyes, slim thorax, wide abdomen. Antenna made up of 11 segments. Adults emit a squeak if disturbed or squeezed to deter predators.

Hosts: The primary hosts are plants in the Lilium and Fritillaria genus. Commonly found on tiger, Easter, Asiatic and oriental lilies. Daylilies (Hemerocallis) do not seem to be affected.

Life Cycle: Overwinter as adults in soil or leaf-litter, emerging in early spring and through June to lay eggs. Eggs are orange and can be found on the underside of lily or fritillary leaves in irregular lines of 3-12. Slug like larvae hatch after 1-2 weeks and feed for 16-24 days. Through development, the orange-green larvae cover themselves in their own frass to deter predators.

Similar species: Cardinal beetle (Pyrochroa serraticornis) which also has a red elytra and black underside.

Monitoring and rapid response: Contact insecticides can be used to control larval feeding on foliage. Products containing Permethrin, Cyhalothrin, Deltamethrin, Pyrethrin and other insecticides labeled for ornamental use have shown to be effective. Imidacloprid has been effective when applied either as a foliage spray or soil drench. Neem oil (Azadiractin) and insecticidal soaps have also been effective.

Credits: The information provided in this factsheet was gathered from Michigan State University Extension and the University of Maine Cooperative Extension bulletin #2450.

Individual species images that appear with a number in a black box are courtesy of the Bugwood.org network (https://www.invasive.org).Individual photo author credits may not be included due to the small display size of the images and subsequent difficulty of reading the provided text. All other images appear courtesy of Google (https://images.google.com).

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