Brown Arborvitae Leafminer (Coleotechnites thujaella)

Taxonomy

Domain	Eukarya
Kingdom	Animalia
Phylum	Arthropoda
Subphylum	Hexapoda
Class	Insecta
Subclass	Pterygota
Infraclass	Neoptera
Superorder	Holometabola
Order	Lepidoptera
Superfamily	Gelechioidea
Family	Gelechiidae
Subfamily	Gelechiinae
Tribe	Litini
Genus	Coleotechnites

Scientific Name

Coleotechnites thujaella

Common Name

leafminer

Maier, C.T.; Lemmon, C.R.; Fengler, J.M.; Schweitzer, D.F.; Reardon, R.C.; Caterpillars on the Foliage of Conifers in the Northeastern United States. Morgantown, WV. USDA Forest Service. Forest Health Technology Enterprise Team Connecticut Agricultural Experiment Station. FHTET-2004-01. March 2004. 151 p.

Description

Brown body with dark brown head, prothoracic shield, and anal plate. Prothoracic shield with light brown anterior margin; narrow, light brown band at hind margin of segments. Up to 8 mm.

Food

Northern white-cedar.

Life Cycle

One generation. Partly grown caterpillar overwinters in its mine. Mature caterpillar present from May to July.

Comments

The brown arborvitae leafminer lives its entire life in a mine that turns dark brown (and later fades to light brown) after the inner tissue has been removed. After feeding is completed, it forms a brown pupa within the mine. This caterpillar is the only brown one that mines northern white-cedar (arborvitae). Several greenish Argyresthia species also infest arborvitae; see the comments for the Canadian arborvitae leafminer, A. canadensis. The brown arborvitae leafminer is one of the most important pests of arborvitae in the Northeast.