Flower eating caterpillar

Caterpillars that eat flowers belong to a number of moth species.

Scientific name

Multiple species including Homoeosoma vagella and Xanthodes congenita.

Description of adult

Adults are variable in form as they belong to a number of species of moths.

Immature stages

Caterpillars are also variable in shape, but any caterpillar found in the developing flower racemes should be suspect. Not all of these species of caterpillars produce silk to web the faecal pellets and damaged raceme together.

Life history

Macadamia flower caterpillar moths lay eggs on the flower panicle. The larvae feed on the florets for about 3 weeks then they pupate in the shelter of the panicle. The pupal stage lasts about 10 days.

Distribution

At least 1 species of these moths occur in all fruit growing districts in Queensland.

Host range

Macadamias, lychee, longan, rambutan, cocoa, tamarillo and durian.

Damage

Minor and sporadic. These insects cause damage to cocoa and tamarillo. The extent of damage varies from crop to crop; in some it is not significant. Flowers can be chewed and webbed together resulting in reduced fruit set.

Control

Action levels are not determined. Weekly inspection of flowers is recommended. Examine for silken matting and larvae. Shaking flower panicles can often help to detect larvae.

Chemical

Only in extreme cases is an insecticide spray warranted. Spray in the late evening when pollinators are less active. Sprays should be directed at the flower panicles.

Chemical registrations and permits

Check the Australian Pesticides and Veterinary Medicines Authority database for chemicals registered or approved under permit to treat this pest on the target crop in your location. Always read the label and observe withholding periods.