Xenotemna pallorana

Status

NATIVE

DOMESTIC SURVEY

Taxonomy

Xenotemna pallorana (Robinson) (Tortricidae: Tortricinae: Archipini)

Synonyms: lata (Tortrix)

Adult Recognition

FWL: 8.5–14.0 mm

Forewing color varies from pale yellow to cream to light brown. Many individuals are unmarked although some exhibit a faint reticulated forewing pattern. Males lack a forewing costal fold. Hindwings are brownish gray, white, or yellowish.

Male genitalia are characterized by a quadrate uncus with two short conical projections at the apicoventral corners; a robust gnathos; and membranous valvae. Female genitalia are characterized by a simple sterigma and signum present as a scobinate patch in the corpus bursae.

Larval Morphology

The following account is summarized from MacKay (1962a)MacKay (1962a):
MacKay, M. R. 1962a. Larvae of the North American Tortricinae (Lepidoptera: Tortricidae). Canadian Entomologist, Supplement 28: 1-182..

Mature larva approximately 16–28 mm in length; width of head 1.4–1.5 mm; head, prothoracic shield green, unmarked; abdomen green; anal fork present with 7-9 teeth; SV group on A1, 2, 7, 8, 9 numbering 3:3:3:2:2.

Detailed figures of larval chaetotaxy are available in MacKay (1962a)MacKay (1962a):
MacKay, M. R. 1962a. Larvae of the North American Tortricinae (Lepidoptera: Tortricidae). Canadian Entomologist, Supplement 28: 1-182..

Similar Species

Adults are similar to Clepsis clemensiana, and the two species are often mixed in collections. Males can be separated by the forewing costal fold, which is present in C. clemensiana and absent in X. pallorana. A genitalic dissection can be used to confirm identity.

The unmarked larvae of X. pallorana may appear similar to those of many other Archipini.

Distribution

Xenotemna pallorana is widespread in the continental United States and southern Canada. It is more common in the east. 

Biology

The following account is summarized from Chapman and Lienk (1971)Chapman and Lienk (1971):
Chapman, P. J., Lienk, S. E. 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..

Xenotemna pallorana completes two annual generations over much of its range. Adults are present May to August. Females lay eggs in masses on the upper surface of leaves. Larvae feed in folded leaves and mid-instar larvae construct a hibernaculum in which overwintering occurs. Feeding resumes in the spring and pupation occurs in the final larval feeding site.

Chapman and Lienk (1971)Chapman and Lienk (1971):
Chapman, P. J., Lienk, S. E. 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. suggest that primary larval hosts are limited to herbaceous legumes such as alfalfa and white sweet clover. Other larval hosts, such as apple, are considered secondary hosts. Xenotemna pallorana has also been reported to cause economic injury to young pines in plantations.

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.