|Crop Knowledge Master|
Amorbia emigratella (Busck)
Ronald F.L. Mau, Extension Entomologist
Jayma L. Martin Kessing, Educational Specialist
Department of Entomology
This pest has a wide host range. It is commonly found on ornamental plants and some fruit trees. Vegetables are not common hosts. Plant hosts of this caterpillar include avocado, broccoli, cacao, citrus, cotton, eggplant, green beans, guava, macadamia, orchids, papaya, passion fruit, potato, rose, sweet potato and tomato. It also attacks many other shrubs, fruit trees and indigenous plants in the mountains (Fullaway and Krauss, 1945).
This caterpillar has been in Hawaii since 1900 and occurs on all major islands except Lanai. It also occurs in Mexico and Costa Rica.
This caterpillar has secretive feeding habits and usually feeds beneath a protective cover. The covering may be a coarse web or a leaf they have attached to the fruit they are feeding on. Caterpillars sometimes reduce marketability of fruits by feeding on outer surfaces of fruits that are in close contact. They are reported to reduce fruit set of papaya when they feed on the blossoms.
Individual eggs are flat, elliptical, finely reticulated, slightly iridescent and approximately 1/25 inch long. They are positioned in a slightly overlapping order in clusters of 65 to 120 on the upper surfaces of leaves (Fullaway and Krauss, 1945). The egg cluster is greenish in color with a white protective covering that extends out past the egg cluster when laid. The eggs turn brownish in color as they reach maturity approximately 10 days after being laid.
Newly hatched larvae are 1/8 inch long. They have a brownish yellow head, black eyes and a light green body. The fully grown larvae are about an inch long. They have pinkish-brown bands on the top and along both sides of their yellow-green bodies. In addition, there is a black line on either side running practically the length of the body. The larval stage is a period of growth in which there are 3 or 4 molts and is completed in 28-35 days.
Pupation occurs within the folded leaf. The 1/3-1/2 inch long pupae are dark to golden brown with two transverse rows of blunt spines at the head and tail regions (Fullaway and Krauss, 1945). The moth emerges in about 10 days.
The wings of the female are 1 to 1-1/6 inch in wingspan. When the moth is at rest, the wings are folded back and only the forewings are visible. The tops of the forewings are yellowish brown with dark bluish gray bands and dark gray streaks, and mottled with darker striations. The hindwings are only visible when the wings are open. The tops of the hind wings are light yellow and mottled with dark brown and black (Fullaway and Krauss, 1945). The underside of the wings is reddish yellow with a black line at the edge. Adult males are slightly smaller and paler in color (Fullaway and Krauss, 1945).
Numbers of this pest increased rapidly when it was introduced into Hawaii. Today, its pest status is reduced probably due to naturally occuring parasitoids. Fullaway and Krauss (1945) report two parasitoids, Trichogramma minutum (Riley) and Brachymeria obscurata (Wlkr.).
No information is available.
Fullaway, D. T. and N. L. H. Krauss. 1945. 193. Amorbia emigratella Busck. pp. 122-123. In: Common Insects of Hawaii. Tongg Publishing Company, Honolulu. 228 pages.