Explanation of Names
DYARI: after the USDA entomologist
Harrison Gray Dyar Jr. (1866-1929), who described hundreds of species and genera of lepidoptera
Identification
Adult: body slender; antennae pectinate (at least in males); forewing brownish-gray with black speckling and lines; AM and PM lines thick, AM line slightly curved, PM line zigzagged or sinuate; two or three black wedges at costa near apex; diffuse whitish patches in basal and anal angle areas; hindwing uniformly brownish-gray except dark thin terminal line
Larva: head light tan with reddish-brown mottling, vertex moderately cleft; body stocky with numerous swellings, rusty brown to gray with white dorsal patches on the second, fourth, and eighth abdominal segments
[adapted from description at Canadian Forest Service]
Range
Alaskan panhandle and British Columbia to California
Season
adults fly from June to October in California
larvae from May to July
Food
larvae feed on foliage of coniferous trees: principal hosts are Western Hemlock and Douglas-fir; other hosts include Western Red Cedar, Amabilis Fir, Grand Fir, Subalpine Fir, Engelmann Spruce, Mountain Hemlock
Life Cycle
one generation per year; overwinters as an egg; pupation occurs in a cocoon on a twig in August, and lasts for approximately 26 days
Remarks
The larva at rest resembles a bird dropping, but it can contort its body into a configuration that looks like a male cone of conifers.
See Also
G. regularia is similar but lacks diffuse whitish patches on the forewing, and apparently occurs only in Arizona (see
pinned adult image of
G. regularia)
No images of other Gabriola species were found on the Internet, and no records north of Oregon were found.
Internet References
pinned adult image plus description, food plants (Jeff Miller, Macromoths of Northwest Forests and Woodlands; USGS)
live larva images plus food plants, distribution, description, biology, seasonality (Conifer Defoliating Insects of British Columbia, Canadian Forest Service)
live larva image plus description, food plants, seasonality (Jeffrey Miller, Caterpillars of Pacific Northwest Forests and Woodlands; USGS)
classification and type specimens (Brian Pitkin, Butterflies and Moths of the World)
presence in California; list of 15 specimen records with dates and locations (U. of California at Berkeley)
Contributed by
Robin McLeod on 11 February, 2006 - 4:34pm
Last updated 24 February, 2008 - 1:09pm
