Mimosa webworm

Homadaula anisocentra Meyrick (Lepidoptera: Galacticidae)

Orientation to pest

Mimosa webworm, Homadaula anisocentra Meyrick, is an invasive moth from China that was first recorded in North America in Washington, D.C., in 1940. Larvae feed on flowers and foliage of the introduced Asian silktree (mimosa) (Albizia julibrissin Durazz.) and the native North American honeylocust (Gleditsia triacanthos L.). Larvae web together areas on which they are feeding. This insect over-winters as pupae encased in cocoons on bark of their host tree or in the leaf litter below. Eggs of first generation moths are laid on leaves and hatch in early to mid-June. There are two generations each year and moths of the second generation moths emerge in August.

Hosts commonly attacked

The caterpillars of this moth feed on the introduced Asian silktree (A. julibrissin) and the native North American honeylocust (G. triacanthos).

Distribution

This insect occurs from Massachusetts and Pennsylvania, south to Florida and west to Mississippi, Kansas and Nebraska.

Images of mimosa webworm

Ashley Bradford, Northern Virginia, Wikipedia Commons 768x512	Stan Gilliam 768x512	Michael Masiuk, Bugwood.org 768x512 / 1536x1024
Figure 1. Adult of mimosa webworm, Homadaula anisocentra	Figure 2. Larva of mimosa webworm	Figure 3. A cocoon of mimosa webworm, the overwintering stage, in a bark crack

Brian Kunkel, University of Delaware, Bugwood.org 768x512 / 1536x1024	Michael Masiuk, Bugwood.org 768x512
Figure 4. Web produced by larvae of the mimosa webworm	Figure 5. Host tree heavily damaged by mimosa webworm

Important biological control agents related to this pest species

Some North American parasitoids attack this species, but parasitism rates are very low (2-4%). However, at least in Iowa one parasitoid, the eulophid Elasmus albizziae attacked 39-47% of the pupae.

Web links for information on mimosa webworm

• Woody Ornamental IPM fact sheet | Pennsylvania State University

Articles

• Heppner, J. B. and G. W. Dekle. 1975. Mimosa webworm, Homadaula anisocentra Meyrick (Lepidoptera: Plutellidae). Entomology Circular No. 157, Division of Plant Industry, Florida Department of Agriculture and Consumer Services.
• Bastian, R. A. and E. R. Hart, E. R. 1989. First-generation parasitism of the mimosa webworm (Lepidoptera: Plutellidae) by Elasmus albizziae (Hymenoptera: Eulophidae) in an urban forest. Environmental Entomology 19: 409-414.
• Sadof, C. S. and R. T. Snyder. 2005. Seasonal abundance of Homadaula anisocentra (Lepidoptera: Plutellidae) and two parasitoids, Elasmus albizziae (Hymenoptera: Elasmidae) and Parania geniculata (Hymenoptera: Ichneumonidae), in an urban forest. Environmental Entomology 34: 70-74.