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Subspecies Eacles imperialis pini - Pine Imperial Moth

Killarney caterpillar - Eacles imperialis Pine Imperial Moth - Eacles imperialis Eacles imperialis pini - Eacles imperialis Warty haired caterpillar - Eacles imperialis Eacles imperialis pini - Eacles imperialis Caterpillar ID request - Eacles imperialis Caterpillar ID request - Eacles imperialis Pine imperial moth - Eacles imperialis - female
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Bombycoidea (Silkworm, Sphinx, and Royal Moths)
Family Saturniidae (Giant Silkworm and Royal Moths)
Subfamily Ceratocampinae (Royal Moths)
Genus Eacles
Species imperialis (Imperial Moth - Hodges#7704)
Subspecies pini (Pine Imperial Moth)
Other Common Names
Canadian Imperial Moth (1)
Synonyms and other taxonomic changes
described in 1950 by Michener
treatment as subspecies follows Ferguson (1971) and Tuskes et al. (1996) (1)
male forewing 42-48 mm; female forewing 47-54 mm

larva length to 80 mm
Adult: compared to E. i. imperialis, upperside of all wings have heavier sprinkling of purple-to-black dots, and underside of all wings have well-defined PM line (2)

Larva: abdominal segments have two paired rows (dorsal and dorsolateral) of large shiny white scoli (fleshy protuberances); spiracles white
northern third of Michigan's lower peninsula, southcentral Ontario from Sault St. Marie in the west to Ottawa in the east, upstate New York, and southeastern Quebec near Montreal; single records from Vermont and the Thunder Bay area of Ontario; type specimens collected in Cheboygan County, Michigan. Populations in northeastern New York and Vermont could be considered somewhat intermediate to E. imperialis imperialis (1)

(northern limit of subspecies imperialis range includes southern Maine, southern New York, lower Niagara peninsula of Ontario, central Michigan, southwestern Wisconsin, and central Iowa)
mostly sandy pine forests and pine plantations (1)
adults fly from June to August

larvae from July to September
larvae feed exclusively on conifers, mainly White Pine and Red Pine; also recorded on Jack Pine, Scotch Pine, and White Spruce

adults do not feed
Life Cycle
one generation per year; overwinters as a pupa in the soil
uncommon and local in Ontario; rare and local in Quebec and elsewhere within its range

mate and come to lights mostly between midnight and 2:30am, about an hour later than E. imperialis imperialis (1)
See Also
nominate subspecies imperialis adult is larger (male forewing 47-59 mm; female forewing 58-68 mm) and wings have lighter spotting above and faint or absent PM lines below

nominate subspecies imperialis larva is larger (95-115 mm), dorsal and dorsolateral scoli much smaller or lacking, and spiracles usually yellow
Internet References
live adult images plus description, larval foodplants, flight dates (Lynn Scott, Ontario)
detailed subspecies account including description of adult and larva, distribution, larval foodplants, biology (Paul M. Tuskes, James P. Tuttle, Michael M. Collins, "The wild silk moths of North America: a natural history of the Saturniidae", courtesy Google Books)
original description of subspecies by Charles Michener (Journal of Kansas Entomological Society, 1950, courtesy
live larva image showing green form (Bill Oehlke,
common name reference and status in Ontario (Natural Heritage Information Centre, Ontario Ministry of Natural Resources)
Works Cited
1.Rare, Declining, and Poorly Known Butterflies and Moths of Forests and Woodlands in the Eastern United States
Dale F. Schweitzer, Marc C. Minno, David L. Wagner. 2011. U.S. Forest Service, Forest Health Technology Enterprise Team, FHTET-2011-01. .
2.MONA - Saturniidae
D.C. Ferguson. 1971. E.W. Classey & R.D.B. Publications Inc.