Other Common Names
Warty Birch Caterpillar (larva)
Synonyms and other taxonomic changes
Drepana bilineata (Packard, 1864)
Falcaria bilineata (Packard, 1864)
Edapteryx bilineata Packard, 1864
syn. Prionia levis Hudson, 1893
Identification
Adult: forewing light brown to orangish-yellow with scalloped outer margin and hooked tip; AM and PM lines brown, straight, parallel; reniform spot a black dot; first brood moths have many dark wiggly lines crossing wing; in second brood individuals, these lines are few or lacking.
hindwing white or pale yellow with small indistinct discal spot and thin brown terminal line
Larva: body purplish or reddish-brown mottled with yellow and covered with warts or tubercles; tail end tapers to a point
Pupa: purple with diffuse black spots, pointed rear end, and covered with fine white powder as though dipped in flour
Range
coast to coast in northern United States and southern Canada (Newfoundland to New Jersey, west to Oregon, north to British Columbia)
Season
The flight period is April to September (two broods).
(1)Food
larvae feed on leaves of alder, birch, poplar
Life Cycle
two generations per year; pupation occurs within a cocoon hidden by a folded leaf
See Also
Arched Hooktip lacks two straight parallel lines on forewing
Rose Hooktip is colored differently and also lacks two straight parallel lines on forewing
Print References
Packard, 1864.
Proceedings of the Entomological Society of Philadelphia, 3:
376.
Powell, J.A. & P.A. Opler, 2009.
Moths of Western North America. University of California Press, pl. 27, fig. 2; p. 202.
(2)Internet References
pinned adult images of first and second brood (CBIF)
University of Alberta E.H. Strickland Entomological Museum pinned adult, plus common name reference [Two-lined Hooktip; adult], habitat, flight season, description, biology, distribution (G.G. Anweiler, U. of Alberta)
live larva, pupa, and adult images plus biology and other info (Jeremy Tatum, Butterflies and Moths of Southern Vancouver Island)
live adult images plus description, food plants, flight season (Lynn Scott, Ontario
distribution in Canada list of provinces (CBIF)
synonyms plus references and links to images (Markku Savela, FUNET)