New York Natural Heritage Program
Blueberry Gray
Glena cognataria (Hübner, 1831)
Insects

General Description [-]
This is a fairly small, plain gray, Geometrid moth with feathered antennae in males.

Characters Most Useful for Identification [-]
This is a fairly small, plain gray, Geometrid moth with feathered antennae in males. It is easily identified by anybody familiar with the group. There are no similar species in New York. Northern specimens tend to be smaller and with subdued markings, compared to the specimen illustrated by Covell (1984).

Best Life Stage for Proper Identification [-]
Adult only.

Behavior [-]
The adults are nocturnal.

Diet [-]
The foodplant has not been documented in New York, but lowbush blueberry (Vaccinium angustifolium and Vaccinium pallidum) are most often reported. Other heaths are probably used as well and Sand Cherry (Prunus pumila) and Pin Cherry (Prunus pensylvanica) are used in New England, which suggests the larvae may be somewhat polyphagous (feeding on many different kinds of food).
Blueberry Gray Images
click to enlarge
The Best Time to See
The phenology is somewhat uncertain, but adults are likely to be present about late May to June and August with two broods. The pupae overwinter in the leaf litter or humus.
J F M A M J J A S O N D
Reproducing Larvae present and active Pupae or prepupae present
The time of year you would expect to find Blueberry Gray reproducing (blue shading), larvae present and active (green shading) and pupae or prepupae present (orange shading) in New York.