Synonyms and other taxonomic changes
Besma quercivoraria (Guenée, )
Metanema quercivoraria Guenée, 
Explanation of Names
Specific name means "oak-eater."
Adult: sexually dimorphic - female forewing pale tan with fine straight PM line, scalloped subterminal line (sometimes absent), and sometimes diffuse gray spot near anal angle; male forewing has brownish-orange or gray shading beyond PM line; wing veins darker than ground color on all wings; black discal dot may be present or absent on forewing and hindwing; all wings have pointed projection mid-way along outer margin in both sexes.
Larva: a twig mimic - body green, brown, or tan with conspicuous reddish or darkened thoracic and abdominal swellings; head reddish-brown, flattened and sloping; vertex somewhat lobed to either side, lobes often bearing pale triangular area, widest behind; second thoracic segment conspicuously swollen; second abdominal segment with small subspiracular and ventral warts; third segment bearing conspicuous lateral and dorsal swellings, and sixth segment with dorsal warts; subtle longitudinal wrinkle forward of spiracle. [adapted from description by David Wagner and Valerie Giles]
Across southern Canada (Newfoundland to British Columbia) and all of United States except California.
Deciduous and mixed woodlands; adults are nocturnal and come to light.
Adults fly from April to September in the south (1)
; May to August in Ontario; late May to July in Alberta.
larvae present from May to October.
Larvae feed on leaves of oak, elm, poplar, willow, white spruce (Picea glauca
, and mostly paper birch (Betula papyrifera
) in southern Canada.
Two generations per year; overwinters as a pupa.
See Rupert (1944) for rearing information and description of life stages. (2)
McGuffin (1987) found no apparent morphological differences between adult Besma quercivoraria and B. endropiaria, but in eastern North America quercivoraria produces two annual broods and endropiaria produces one (Wagner et al, 2001).
forewing lacks scalloped subterminal line, wings veins are paler than ground color, and species occurs only in the west.
) forewing lacks scalloped subterminal line and flies in the fall
forewing has double PM line and lacks subterminal line.
Covell, p. 370, plate #53, 19 & 20 (1)
McGuffin, W.C. 1987. Guide to the Geometridae of Canada (Lepidoptera): II. Subfamily Ennominae, 4. 182 pp.
Wagner, D.L., D.L. Ferguson, T.L. McCabe, and R.C. Reardon. 2001. Geometroid Caterpillars of Northeastern and Appalachian Forests. 239 pp.