Adult Recognition
FWL: 7.0-9.0 mm
Forewings are black with distinctive yellow, orange, and silvery markings and a conspicuous ocellus with alternating black and yellow bands. Hindwings are dark grayish brown with white fringe.
Adults of E. formosana have forewing coloration similar to some Olethreutes and related genera (Syricoris, Pristerognatha, etc.), although most of these species lack a defined ocellus. In North America, Eucosmomorpha nearctica may appear similar, but adults lack the black forewing ground color. A genitalic dissection can be used to easily separate the various genera listed here.
Enarmonia formosana pheromone traps in Washington have captured a wide variety of tortricines and olethreutines as well as moths in other families. Wing pattern is usually sufficient to separate E. formosana from non-target species.
Larval Morphology
Last instar larvae are approximately 8-11 mm in length. The abdomen is whitish to gray to pinkish with darker gray pinacula. The head and prothoracic shield are brown; sometimes the shield is marked with black on the posterolateral margin.
Biology
Enarmonia formosana completes two annual generations. Adults are present from May to September.
Females lay eggs singly or in small clusters on tree bark. Larvae tunnel into the bark and feed under the surface. Older trees are usually more heavily infested; wounded tissue and the base of the tree are favored feeding sites. Larval damage is characterized by "frass tubes" consisting of fecal pellets, silk, and tree sap, which protrude from larval feeding sites. Overwintering occurs as a larva. Pupation occurs in the larval feeding tunnels close to the surface of the bark or within the frass tubes.
Host plants
Larvae of Enarmonia formosana are a pest of fruit trees in the family Rosaceae. Larval damage results in swellings and cankers, and branches or entire trees may be killed. Larvae have also been recorded on beech (Fagaceae).
| Family | Genus/species | Common name |
| Fagaceae | Fagus sylvatica L. | European beech |
| Rosaceae | Cydonia Mill. | cydonia |
| Rosaceae | Malus Mill. | apple |
| Rosaceae | Malus sylvestris (L.) Mill. | European crab apple |
| Rosaceae | Prunus armeniaca L. | apricot |
| Rosaceae | Prunus avium (L.) L. | sweet cherry |
| Rosaceae | Prunus domestica L. | European plum |
| Rosaceae | Prunus dulcis (Mill.) D. A. Webb | sweet almond |
| Rosaceae | Prunus laurocerasus L. | cherry laurel |
| Rosaceae | Prunus persica (L.) Batsch | peach |
| Rosaceae | Pyrus communis L. | common pear |
| Rosaceae | Sorbus L. | mountain ash |
Distribution
Enarmonia formosana is widely distributed from western Europe and northern Africa to Asia Minor, Russia, and Siberia. The first North American records are from British Columbia in 1989; it was subsequently found in western Washington in 1991 and has spread to Oregon.
References
Bradley, J. D., W. G. Tremewan and A. Smith. 1979. British Tortricoid Moths - Tortricidae: Olethreutinae. The Ray Society, London, England. 336 pp.
Dang, P. T. & D. J. Parker. 1990. First records of Enarmonia formosana (Scopoli) in North America (Lepidoptera: Tortricidae). Journal of the Entomological Society of British Columbia. 87: 3-6.
Dickler, E. 1991. Tortricid pests of pome and stone fruits, Eurasian species, pp. 435-452. In L. P. S. van der Geest and H. H. Evenhius [eds.], Tortricid Pests: Their Biology, Natural Enemies, and Control. World Crop Pests, Vol. 5. Elsevier, Amsterdam.
Meijerman, L. and S. A. Ulenberg. 2000. Arthropods of Economic Importance: Eurasian Tortricidae. Arthropods of Economic Importance series. ETI/ZMA.
Razowski, J. 2003. Tortricidae of Europe, Vol. 2, Olethreutinae. Frantisek Slamka, Slovakia. 301 pp.
Tanigoshi, L. K. & P. Stary. 2003. Distribution, habitats and host plants of the cherry bark tortrix, Enarmonia formosana (Scopoli) in the Czech Republic (Lepidoptera, Tortricidae). Journal of Pest Science. 76: 41-43.
