Superfamily Geometroidea (Geometrid and Swallowtail Moths)
Family Geometridae (Geometrid Moths)
Subfamily Ennominae
Tribe Bistonini
Genus Lycia
Species rachelae (Twilight Moth - Hodges#6653)
Hodges Number
6653
Synonyms and other taxonomic changes
Lycia rachelae (Hulst, 1896)
* phylogenetic sequence #196525
Explanation of Names
Twilight: adults are most active during the hour before sunset, possibly in response to the cold nights of early spring
Numbers
one of 3 species in this genus in North America
very rare in northeast: threatened, or a species of special concern in several northeastern states such as Maine, Massachusetts, New Hampshire, Pennsylvania, Vermont; first Ontario record was 31 March 2006 at Dunrobin near Ottawa
Size
wingspan of males 35 - 37mm, females essentially wingless (1)
Identification
Adult: wings reduced or absent in female, which cannot fly; male wings translucent gray with prominent black veins and dull orangish strip along costa; forewing with 3 dark lines crossing wing, middle line heaviest; hindwing with dark discal spot; male antennae pectinate; body of both sexes bulky, hairy, black with mix of pale hairlike scales and orange middorsal stripe on abdomen
Larva: body gray with fine black and orange markings and white and orange lateral stripe
Range
Alaska and Yukon south to northern California and Colorado, east to Quebec, Maine, and northern tier of northeastern states
Habitat
pine/oak barrens, boreal forest, early successional areas containing birch and poplar
Season
adult male flies from late March to early June; peak in April or the week after snow melt (1)
Food
larvae feed on leaves of alder, apple, birch, buffaloberry (Shepherdia canadensis), chokecherry, elm, poplar, willow, and other woody plants in the rose family
adults do not feed
Life Cycle
eggs are laid in goups under loose bark (1), and hatch in late spring or early summer; overwinters as a pupa in soil; one generation per year
Remarks
Males very rarely appear at lights, likely because the flight finishes before full darkness sets in.
See Also
Stout Spanworm Moth (Lycia ursaria) male wings are heavily speckled with dark and pale scales, not translucent gray.
. . . . . . . . . . . . . .
Woolly Gray (Lycia ypsilon) male wings with speckled patches of black and white, not translucent gray.
Print References
Powell, J. A., and P. A. Opler 2009. Moths of Western North America. pl. 28.31; p. 211.(2)
Rindge, Frederick H. 1975. A revision of the New World Bistonini, (Lepidoptera, Geometridae). Bulletin of the AMNH ; v. 156, article 2.(3)
