Explanation of Names
FURCULA: from the Latin "furca" (a fork); refers to the long forked anal prolegs of the larva
Numbers
6 species in North America (
nearctica.com)
5 species in Canada (CBIF)
Identification
Adult: forewing white to off-white to gray (with dark gray patches in median area and along costa near apex in 4 species); AM and terminal lines composed of black dots; some yellowish or orange markings usually present in 4 species; hindwing white or pale grayish with terminal line of black dots and usually dark discal spot
Larva: body greenish-yellow to green with bluish-green or brown saddle in middle of back; anal prolegs modified into pair of long narrow tail-like projections, giving the appearance of a forked tail
Range
all of United States and southern Canada, plus southern Yukon and Northwest Territories - varies according to species
F. borealis: eastern 2/3 of US, and eastern half of Canada (see
distribution map)
F. cinerea: all of US and southern Canada, plus Northwest Territories (see
map)
F. modesta: across northern US and southern Canada, south in the west to California and Arizona (see
map)
F. nivea: western US - mostly the southwest but one record from North Dakota (see
map)
F. occidentalis: southern Yukon across southern Canada and northern US (see
map)
F. scolopendrina: patchily distributed in northeastern states and 4 eastern provinces; widely distributed in western states and 3 western provinces; missing from middle of continent (see
map)
Habitat
deciduous and mixed woods and shrublands
Season
adults fly from April to October in the south; May to August in the north
Food
larvae feed on leaves of birch, cherry, poplar, willow
Life Cycle
two generations per year in the south; one in the north
Internet References
pinned adult images of the 5 species occurring in Canada (CBIF)
pinned adult image of the 6th species,
F. nivea (Bruce Walsh, Moths of Southeastern Arizona)
distribution list of 5 species in eastern Canada (CBIF)
distribution list of 4 species in western Canada (CBIF)
Contributed by
Troy Bartlett on 16 February, 2004 - 12:32pm
Additional contributions by
Robin McLeodLast updated 20 December, 2015 - 5:29pm