FWL: 10.0-14.5 mm (male); 13.5-17.5 mm (female)
Male forewing color varies from pale tan to rust to dark gray brown. Many individuals have a dark costal spot that is a remnant of the median fascia or more well-defined transverse markings. Females have a more uniform rust to tan forewing with obscured marking. Males lack a forewing costal fold. A dorsal pit is present on the second abdominal segment and ocelli are absent.
Few other North American tortricids are similar in size or appearance to Amorbia, and this is one of the few tortricid genera in which the adults lack ocelli. The two Amorbia species treated here can be separated by the number of dorsal pits on the abdomen: dorsal pits on segments 2-6 for Amorbia emigratella versus a single dorsal pit on segment 2 for A. cuneana.
Last instar larvae are approximately 25mm long. The head and prothoracic shield are tan and marked with dark brown to black lateral bands; these lateral bands can be used to distinguish late instar Amorbia larvae from those of many other tortricids. Early instars lack the distinctive dark bands, and morphological identification of early instar larvae may be difficult or impossible.
For more information on Amorbia larvae, please consult the fact sheet and keys on LepIntercept - An identification resource for intercepted Lepidoptera larvae.
Amorbia cuneana completes two generations per year in northern California, where adults are present in May through June and again in October. In southern California, A. cuneana is multivoltine and adults have been recorded every month of the year.
Larvae feed on leaves, skeletonizing them in early instars and consuming the entire leaf in later instars. Larvae also web leaves to fruit and feed on the skin of fruit in a cluster, sometimes causing economic damage.
Amorbia cuneana can be a significant pest of avocado in California. Its putative synonym, A. essigana Busck, was described as an avocado pest in southern California in 1929, and it is possible that avocado-feeding populations may represent this "pheromone race."
Amorbia cuneana feeds on plants in several families although it is usually recognized as a pest of avocado.
|Family ||Genus/species ||Common name|
|Caprifoliaceae ||Lonicera japonica Thunb. ||Japanese honeysuckle|
|Ericaceae ||Arbutus menziesii Pursh ||Pacific madrone|
|Ericaceae ||Arctostaphylos glauca Lindl. ||bigberry manzanita|
|Ericaceae ||Arctostaphylos insularis Greene ex Parry ||island manzanita|
|Ericaceae ||Arctostaphylos patula Greene ||greenleaf manzanita|
|Ericaceae ||Arctostaphylos Adans. ||manzanita|
|Grossulariaceae ||Ribes sanguineum Pursh ||redflower currant|
|Lamiaceae ||Trichostema lanceolatum Benth. ||vinegarweed|
|Lauraceae ||Cinnamomum camphora (L.) J. Presl ||camphortree|
|Lauraceae ||Laurus nobilis L. ||sweet bay|
|Lauraceae ||Persea americana Mill. ||avocado|
|Lauraceae ||Persea Mill. ||bay|
|Lauraceae ||Umbellularia californica (Hook. & Arn.) Nutt. ||California laurel|
|Pinaceae ||Abies concolor (Gord. & Glend.) Lindl. ex Hildebr. ||white fir|
|Pinaceae ||Pseudotsuga menziesii (Mirb.) Franco ||Douglas-fir|
|Rhamnaceae ||Ceanothus arboreus Greene ||feltleaf ceanothus|
|Rhamnaceae ||Ceanothus leucodermis Greene ||chaparral whitethorn|
|Rhamnaceae ||Ceanothus sorediatus Hook. & Arn. ||jimbrush|
|Rosaceae ||Heteromeles arbutifolia (Lindl.) M. Roem. var. arbutifolia ||toyon|
|Rosaceae ||Lyonothamnus floribundus A. Gray ||Catalina ironwood|
|Rosaceae ||Prunus ilicifolia (Nutt. ex Hook. & Arn.) D. Dietr. ||hollyleaf cherry|
|Rosaceae ||Prunus ilicifolia (Nutt. ex Hook. & Arn.) D. Dietr. ssp. lyonii (Eastw.) P.H. Raven ||hollyleaf cherry|
|Rosaceae ||Pyracantha M. Roem. ||firethorn|
|Rutaceae ||Citrus L. ||citrus|
|Ulmaceae ||Ulmus americana L. ||American elm|
|Vitaceae ||Vitis L. ||grape|
Amorbia cuneana is found along the Pacific Coast from southwestern Canada south to Baja California and east to Arizona and Idaho.
Faber, B. A., J. G. Morse and M. S. Hoddle. 2010. UC IPM Pest Management Guidelines - Avocado. University of California IPM Online. http://www.ipm.ucdavis.edu/PMG/selectnewpest.avocado.html.
Hoffman, M. P., L. M. McDonough and J. B. Bailey. 1983. Field test of the sex pheromone of Amorbia cuneana (Walsingham) (Lepidoptera: Tortricidae). Environmental Entomology. 12: 1387-1390.
Phillips-Rodriguez, E. and J. A. Powell. 2007. Phylogenetic relationships, systematics, and biology of the species of Amorbia Clemens (Lepidoptera: Tortricidae: Sparganothini). Zootaxa. 1670. 109 pp.
Powell, J. A. and P. A. Opler. 2009. Moths of western North America. University of California Press, Berkeley. 369 pp.
Figs. 7-9: University of California Statewide IPM Program (UC IPM Web Site)