Pammene fasciana

Status

EXOTIC

PORT INTERCEPT

Taxonomy

Pammene fasciana (Linnaeus) (Tortricidae: Olethreutinae: Grapholitini)

Common names: chestnut leafroller

Synonyms: herrichiana (Carpocapsa), juliana (Philalcea), nimbana (Carpocapsa), trinotana (Tortrix)

Adult Recognition

FWL: 6.5–8.5 mm

Forewings are white and gray with a large ocellus consisting of a leaden-metallic center bar surrounded by black and yellow dashes. Adults are not sexually dimorphic. Males lack a forewing costal fold. Hindwings are brown.

Male genitalia are characterized by the absence of an uncus and several cornuti in the vesica. Female genitalia are characterized by two thorn-like signa and a short ductus bursae with a sclerotized ring.

Larval Morphology

The following account is summarized from Brown and Komai (2008)Brown and Komai (2008):
Brown, J. W., Komai, F. 2008. Key to larvae of Castanea -feeding Olethreutinae frequently intercepted at U.S. ports-of-entry (Lepidoptera : Tortricidae). Tropical Lepidoptera Research. 18(1): 2-4..

Mature larva approximately 13–15 mm in length; head light brown or yellowish brown with darker mottling; prothoracic shield whitish with dark dots; body grayish white with large, black, conspicuous pinacula; anal shield brown with darker brown dots; anal fork present; SV group on A1, 2, 7, 8, 9 most often 3:3:2:2:1 but variable.

Similar Species

The majority of Pammene are Palearctic, with over 90 species present in the region. Only six species are present in the Nearctic, and all can be distinguished from P. fasciana by wing pattern. A genitalic dissection can be used to confirm the identity of questionable or worn individuals.

Other tortricid Castanea pests include Cydia fagiglandana, C. glandicolana, C. kurokoi, C. splendana, and Fibuloides aestuosa. Brown and Komai (2008)Brown and Komai (2008):
Brown, J. W., Komai, F. 2008. Key to larvae of Castanea -feeding Olethreutinae frequently intercepted at U.S. ports-of-entry (Lepidoptera : Tortricidae). Tropical Lepidoptera Research. 18(1): 2-4. provide a description and key to larvae of these species. Pammene fasciana larvae can be distinguished by the following characters: whitish abdomen with large, dark, conspicuous pinacula; SV setal counts on A1,2,7,8,9 as 3:3:2:2(1):1; three L setae on A9 on single pinaculum; distance between V setae on A9 greater than distance between Vs on A8; crochets on prolegs uniordinal (or irregularly biordinal); number of crochets on prolegs 30–33; anal comb present.

Distribution

Pammene fasciana is distributed from western Europe east to Ukraine.

Biology

The following account is summarized from Bogenschütz (1991)Bogenschütz (1991):
Bogenschütz, H. 1991. Eurasian species in forestry, pp. 673–709. In: van der Geest, L. P. S., Evenhuis, H. H. (eds.), Tortricid pests: their biology, natural enemies, and control. World Crop Pests, Vol. 5. Elsevier, Amsterdam..

Pammene fasciana completes a single generation per year. Adults are present June-July. Males fly after sunrise and again in the afternoon; females also fly at night.

Females lay eggs singly or in small groups along the veins on the leaves of the host plant. Larvae bore into nuts and feed inside. When the nuts fall from the tree, the larvae bore out of the nut and create a cocoon under tree bark or moss in which to overwinter. Pupation occurs the following spring.

Larvae of P. fasciana are important pests of chestnut (Castanea sativa). Other preferred hosts include Quercus and Fagus.

Plant Associations

View full screen host table here

Links

Additional photos and a distribution map of this species in North America are available at Moth Photographers Group.