Cydia splendana

Status

EXOTIC

PORT INTERCEPT

Taxonomy

Cydia splendana (Hübner) (Tortricidae: Olethreutinae: Grapholitini)

Common names: chestnut fruit tortrix, acorn moth

Synonyms: bicolorana (Tinea), bicolorata (Tinea), glandella (Tortrix), pencleriana (Tortrix), penkleriana (Tortrix), reaumurana (Carpocapsa)

Adult Recognition

FWL: 6.5–10.5 mm

Forewings are light gray to gray. The distal one-third of the wing is marked with a dark-brown to black subtriangular patch that surrounds the purplish ocellus. Hindwings are dark grayish brown.

Male genitalia are characterized by the absence of an uncus and elongate, apically rounded valvae with only a slight constriction of the neck. Female genitalia are characterized by an extremely thin ductus bursae and a large, globose corpus bursae with two small horn-like signa present.

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 yellowish brown; prothoracic shield and anal shield yellow; body grayish green or yellowish white; pinacula concolorous with body; SV group on A1, 2, 7, 8, 9 numbering 3:3:2:1:1; anal fork is absent. Meijerman and Ulenberg (2000)Meijerman and Ulenberg (2000):
Meijerman, L., Ulenberg, S. A. 2000. Arthropods of Economic Importance: Eurasian Tortricidae. Arthropods of Economic Importance series. ETI/ZMA. incorrectly state that an anal fork is present.

Similar Species

Adults may appear similar to those of other Cydia species. Cydia kurokoi is very similar but only occurs in Asia. Cydia fagiglandana is darker overall and lacks a well-defined purplish ocellus. Cydia pomonella is a more uniform gray, and the ocellus is edged with gold or copper scales. A genitalic dissection can be used to confirm identity of the species listed here.

Other tortricid Castanea pests include C. fagiglandana, C. glandicolana, C. kurokoi, Fibuloides aestuosa, and Pammene fasciana. 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. Cydia splendana larvae can be distinguished by the following characters: whitish abdomen with concolorous pinacula; distance between V setae on A9 slightly to conspicuously greater than those on A8; number of crochets on prolegs less than 18; anal comb absent.

Distribution

Cydia splendana is widely distributed throughout Europe. Records from Asia are likely of a different species (see Cydia kurokoi).

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..

Cydia splendana completes a single annual generation. Adults are present in June to July in Central and Northern Europe and August to September in Southern Europe.

Females lay eggs singly on young fruit or on leaves near fruit. Early instars tunnel into fruit and feed inside and a single fruit generally supports one larva. Larval-infested fruit drop to the ground early. Overwintering occurs as a late instar larva under bark or in the soil. Pupation occurs the following spring.

Larvae of C. splendana are important pests of chestnut (Castanea sativa). Other preferred hosts include Quercus, Fagus, and Juglans.

Plant Associations

View full screen host table here