Adult Recognition
FWL: 3.5-5.0 mm
Adults range in color from light to dark. Light individuals have silvery striae and darker contrasting fasciae while dark individuals lack a well-defined forewing pattern. Males have a conspicuous patch of dark sex scales on the dorsal surface of the hindwing. Male genitalia are characterized by the unconstricted valval neck, which is nearly as wide as the cucullus. Female genitalia are characterized by a triangular ostium.
Dark individuals may appear similar to Grapholita molesta, but are generally much smaller. In western North America, Grapholita libertina is similar in appearance to dark G. packardi in both forewing pattern and male genitalia, but G. libertina males lack a patch of dark sex scales on the hindwing.
Larval Morphology
Late instar larvae are approximately 8-9 mm in length with a pale-reddish abdomen. The head is yellowish brown with darker mottling. The prothoracic and anal shields are brown. Pinacular are moderately large. An anal comb is present with 4-6 teeth.
Larvae may appear similar to those of many other species of Grapholita and Cydia. Cydia pomonella larvae can be separated from G. packardi by the absence of an anal fork and their larger size. Larvae of Grapholita molesta are similar but generally larger. Larvae of G. packardi and G. prunivora are very similar, although the pinacula on the 8th and 9th abdominal segment are more prominent in G. packardi, and the abdomen of G. prunivora is more reddish, especially in preserved specimens.
Biology
Grapholita packardi completes 2-3 generations per year. Adults are present in May and June.
Females lay eggs singly on terminal shoot leaves. Larvae feed inside the shoots or fruit; Chapman and Lienk (1971) found considerable variation in feeding records suggesting that larvae behave differently on different hosts or that a species complex is involved. Overwintering occurs on the host in a cocoon and pupation occurs the following spring.
Larval damage is characterized by injured fruit, early fruit drop, and/or stunted or dead shoots.
Host plants
Larvae of G. packardi feed on many common fruit crops in the families Rosaceae and Ericaceae. It is possible that hawthorn (Crataegus) is the native host.
Family | Genus/species | Common name |
Ericaceae | Vaccinium L. | blueberry |
Rosaceae | Crataegus L. | hawthorn |
Rosaceae | Malus Mill. | apple |
Rosaceae | Malus pumila Mill. | paradise apple |
Rosaceae | Prunus domestica L. | European plum |
Rosaceae | Prunus L. | |
Rosaceae | Prunus serotina Ehrh. | black cherry |
Rosaceae | Pyracantha M. Roem. | firethorn |
Rosaceae | Pyrus communis L. | common pear |
Rosaceae | Rosa L. | rose |
Distribution
Grapholita packardi is widely distributed in eastern North America. It is also present in the Pacific Northwest (Washington and British Columbia) and likely other fruit-growing regions of the West.
References
Chapman, P. J. and S. E. Lienk. 1971. Tortricid fauna of apple in New York (Lepidoptera: Tortricidae); including an account of apple's occurrence in the state, especially as a naturalized plant. Spec. Publ. Geneva, NY: New York State Agricultural Experiment Station. 122 pp.
Gilligan, T. M., D. J. Wright and L. D. Gibson. 2008. Olethreutine moths of the midwestern United States, an identification guide. Ohio Biological Survey, Columbus, Ohio. 334 pp.
Heinrich, C. 1926. Revision of the North American moths of the subfamilies Laspeyresiinae and Olethreutinae. Bulletin of the U.S. National Museum. 132: 1-216.
Komai, F. 1999. A taxonomic review of the genus Grapholita and allied genera (Lepidoptera: Tortricidae) in the Palaearctic region. Entomologica Scandinavica Supplement 55. 226 pp.
MacKay, M. R. 1959. Larvae of the North American Olethreutidae (Lepidoptera). Canadian Entomologist Supplement 10: 1-338.
Weires, R. and H. Riedel. 1991. Other tortricids on pome and stone fruits, North American species, pp. 313-434. In: L. P. S. van der Geest, H. H. Evenhuis (eds.), Tortricid pests, their biology, natural enemies and control. Elsevier, Amsterdam, The Netherlands.