Caloptilia fraxinella

(Ely, 1915)

Ash Leaf Cone Roller, Ash Leaf Cone Roller Moth

Caloptilia fraxinella is a leaf-mining in the Gracillariidae. Native to North America, it has become a significant pest of horticultural ash trees (Fraxinus spp.) in Canadian Prairie cities and parts of the United States. The exhibits an unusual with a 9-month reproductive ; adults eclose in summer, overwinter, and mate the following spring. Larvae mine ash leaves and eventually roll leaflets into cones for .

Caloptilia fraxinella 162552509 by Dan MacNeal. Used under a CC BY 4.0 license.

Prays fraxinella (7285073138) by Ben Sale from UK. Used under a CC BY 2.0 license.

Caloptilia rufipennella (14711786431) by Ben Sale from UK. Used under a CC BY 2.0 license.

Pronunciation

How to pronounce Caloptilia fraxinella: //ˈkæloʊptɪliə ˌfræksɪˈnɛlə//

These audio files are automatically generated. While they are not always 100% accurate, they are a good starting point.

Identification

are small with typical Gracillariidae . Larvae are leaf miners with five instars; fourth-instar larvae are distinguished by their of dispersing from the mined leaflet to a new leaflet, which they roll into a cone for . This cone-rolling behavior is the source of the and distinguishes it from other Caloptilia that do not form such structures.

Images

Habitat

Urban forests and horticultural plantings of ash trees (Fraxinus spp.) in prairie and suburban environments. In its introduced range in the Canadian Prairie Provinces, it is associated with ornamental green ash (Fraxinus pennsylvanica) and black ash (F. nigra) in city plantings.

Distribution

Native to eastern North America: Canada (Québec, Ontario, Saskatchewan, Alberta) and United States (Michigan, Vermont, Ohio, Connecticut, New York, Maine). Introduced and established in urban forests of the Canadian Prairie Provinces, particularly Edmonton, Alberta.

Seasonality

eclose in July and enter reproductive . occurs as adults. Mating and oviposition occur in spring (May), timed to coincide with ash bud flush. Oviposition is constrained to a approximately 3-week period shortly after bud flush.

Diet

Larvae feed on Fraxinus (Fraxinus americana, F. mandshurica, F. nigra, F. pennsylvanica) and Ligustrum species. They mine the leaves of their plant. have been observed feeding on sources including sucrose solutions and buckwheat (Fagopyrum esculentum) flowers in laboratory studies.

Host Associations

Fraxinus pennsylvanica - larval (green ash)Primary in Canadian Prairie urban forests
Fraxinus nigra - larval (black ash) in introduced range
Fraxinus americana - larval
Fraxinus mandshurica - larval
Ligustrum - larval level association
Apanteles polychrosidis - primary Native braconid that has shifted to this in Edmonton, Alberta; primary agent

Life Cycle

Five larval instars. Fourth-instar larvae disperse from the mined leaflet to a new leaflet, roll it into a cone, and pupate within. eclose from rolled leaf cones. Adult lifespan is extended by a 9-month reproductive ; occurs in July, with in reproductive diapause until spring mating.

Behavior

Mated females orient to volatile organic chemicals (VOCs) released from ash seedlings for location. Male response to female is plastic and most acute when reproductively active in spring. overwinter in sheltered locations. Females show oviposition site preference for lower and south side of trees during early and mid-oviposition periods.

Ecological Role

Herbivore and on ash trees. In its introduced range in prairie cities, it functions as a pest of urban forest trees. Serves as for native Apanteles polychrosidis, which has shifted to exploit this .

Human Relevance

Significant pest of horticultural and ornamental ash trees in Canadian Prairie cities. Damage from leaf mining and cone-rolling affects aesthetic value of urban plantings. Subject of research and efforts using . use is undesirable in urban centers, making biological control preferred.

Similar Taxa

Other Caloptilia speciesMany Caloptilia are leaf miners on various plants; C. fraxinella is distinguished by cone-rolling and specific association with Fraxinus hosts
Caloptilia blandellaWalnut-feeding with different association (Juglans vs. Fraxinus)