# Lily leaf beetle (Lilioceris lilii) > A bright red beetle that defoliates true lilies and related plants and is a serious garden pest in many regions. Source: https://insectscanner.com/species/lily-leaf-beetle/ (updated 2026-10-10) ## Is it dangerous? **Non-toxic.** Lily leaf beetles do not have venom and are not dangerous to humans. They do not sting; adults can be handled but may secrete defensive fluids and are best removed by hand-picking into soapy water or wearing gloves. There are no known medical risks from their bite or contact. **Pets:** Not toxic to pets. Large infestations might attract pets to eat beetles but they are not considered poisonous. Normal pet supervision and preventing ingestion of large amounts of insects is advised. ## Quick facts - Scientific name: Lilioceris lilii - Also called: Red lily beetle, Scarlet lily beetle - Order: Coleoptera (Beetles) - Family: Chrysomelidae (Leaf beetles) - Size: 6-9 mm long - Colours: Scarlet red, Jet black, Orange (eggs/young larvae) - Habitat: Gardens, cultivated beds and nurseries where lilies, fritillaries and related plants grow; edges of woodlands and meadows in native range. - Range: Native to Europe and parts of Asia; introduced and now established in parts of North America (including northeastern USA and Canada) and reported elsewhere as an invasive pest. - Active: Spring to late summer (adults emerge in spring after overwintering and are active through the growing season); mostly daytime feeders. - Lifespan: Adults live several weeks to a few months, depending on climate and food availability; overwintering occurs as adults in soil or plant debris. - Effect on plants: Garden pest - Pest: yes ## Overview Lilioceris lilii is a small, conspicuously red leaf beetle that feeds on members of the lily family (Liliaceae) and related garden plants. Native to Eurasia, it has become an invasive pest in parts of North America where it can rapidly defoliate cultivated lilies, fritillaries and related ornamentals. Adults and larvae both feed on leaves, stems and flowers; larvae often cover themselves with a sticky dark fecal shield which makes them easy to recognise. Control focuses on monitoring, hand-picking and targeted insecticides; biological control using parasitoid wasps from the beetle's native range has been introduced in parts of North America. ## How to identify it Adults are elongated oval beetles with bright red elytra (wing covers) and a black head, antennae and legs. They are smooth and somewhat shiny. Larvae are soft, slug-like and orange to brown when young but typically appear dark or black because they carry a sticky clump of their own excrement and shed skins (a fecal shield) on their backs. Eggs are yellow-orange, laid in clusters on the underside of leaves. - Adults bright scarlet red elytra with black head, legs and antennae; 6-9 mm long. - Larvae carry a sticky dark fecal shield on their backs, making them appear black and slug-like. - Egg clusters of yellow-orange laid on the underside of leaves. - Gregarious feeding and rapid leaf skeletonisation on lilies is a telltale sign. ## Lookalikes - **Black-headed cardinal beetle** (Pyrochroa coccinea): Also red with a black head, but larger (14-20 mm) and flatter, with comb-like antennae and a red pronotum continuous with the elytra; found on flowers, tree stumps and dead wood rather than feeding on lilies. - **Cardinal beetle** (Pyrochroa serraticornis): Cardinal beetles are larger and often found on flowers; they have different body proportions and antennae compared with the smaller, more rounded lily leaf beetle. ## Life cycle - **Egg:** Clusters of 10-20 yellow-orange eggs are deposited on the underside of host leaves; eggs hatch in about 1 week depending on temperature. - **Larva (grub):** Larvae are soft-bodied and initially orange but commonly covered in a dark fecal shield; they feed gregariously, skeletonising leaves and can defoliate shoots. - **Pupa:** Mature larvae drop to the soil or hide in leaf litter and pupate in the ground or in debris; pupation lasts 2-3 weeks in warm conditions. - **Adult:** Adults emerge in spring, are flight-capable, feed on foliage and flowers, mate and produce the next generation; adults may overwinter in soil or plant debris. ## Diet and predators - Young eat: Leaf tissue of lilies and related plants; larvae feed gregariously and skeletonize leaves. - Adults eat: Leaves, stems and flowers of lilies, fritillaries and related ornamental plants. - Predators of the young: Natural enemies include birds and predatory insects; in native range larval parasitoid wasps attack larvae. In invaded areas natural control is limited. - Predators of adults: Birds and predatory insects may eat adults; ants and ground beetles may prey on larvae or pupae in soil. ## Effect on plants and gardens Feeds heavily on true lilies (Lilium spp.), fritillaries (Fritillaria), and related ornamental plants. Adults chew holes in leaves and flowers; larvae skeletonize leaves. Repeated defoliation can weaken plants and reduce flowering, and severe infestations can kill young plants. ### How to get rid of it Regular inspection in spring and early summer is critical. Hand-pick adults and larvae into a jar of soapy water or crush them. Destroy egg clusters on leaf undersides. For larger outbreaks, targeted insecticides (systemic or contact, applied according to label directions) can be effective; some gardeners use pyrethroid or systemic products where legal and appropriate, but these can also harm bees and other pollinators, and outdoor use of neonicotinoids such as imidacloprid is restricted in some places, including the EU. Neem-based (azadirachtin) sprays can control young larvae. Parasitoid wasps from the beetle's native range have been released as biological control in parts of North America. Rotate control methods and follow local regulations; always follow label instructions and consider beneficial insects. ## Where and when to find it Look on lily and fritillary leaves and flower stems. Check undersides of leaves for yellow-orange egg clusters and examine leaves for larvae carrying dark fecal shields. - Best time: Spring through summer when lilies are leafing and flowering; daytime is best for observing adults feeding on foliage. - Tips: Inspect plants weekly in spring, carefully flip leaves to check for eggs, and photograph both adults and larvae from above and the side to show the fecal shield. ## Fun facts - Larvae carry a sticky fecal shield that helps hide them from predators and is a distinctive identification feature. - Despite the bright warning colour, this beetle is not dangerous to humans but is one of the most damaging pests of garden lilies. - It was accidentally introduced to North America in the 20th century and spread rapidly in regions with ornamental lilies. ## Frequently asked questions ### Do lily leaf beetles bite? No — they do not bite people as a defensive or feeding behaviour. Handling may cause them to release a foul-tasting secretion but they are not harmful to humans. ### Why are lily leaf beetles on my lilies? Lilies and related plants are their preferred food. Adults are attracted to the plants to feed and lay eggs on the underside of leaves; larvae then hatch and feed heavily. ### Will they kill my lilies? Severe, repeated infestations can weaken or kill young plants and greatly reduce flowering. Mature plants often survive a single season of defoliation but repeated damage reduces vigor. ### How do I get rid of lily leaf beetles? Inspect plants regularly in spring. Hand-pick adults and larvae into soapy water, remove and destroy egg clusters, and use targeted insecticides or approved systemic treatments for heavy infestations. Consider local biological control initiatives where available. ### Are there natural predators or biological controls? In its native range parasitic wasps and other natural enemies help control populations. In invaded regions natural enemies are fewer, but biological control programs introducing specialist parasitoids have been initiated in some places. --- More about this species: [iNaturalist](https://www.inaturalist.org/taxa/55761), [Wikipedia](https://en.wikipedia.org/wiki/Scarlet_lily_beetle). Identify insects and spiders from a photo with the Insect Scanner iPhone app: https://apps.apple.com/app/id1543946563?pt=126685406&ct=web-markdown&mt=8 Identification from photos is never certain: don't handle insects you can't identify, and get medical advice for bites, stings or allergic reactions.