Other Common Names
Filament Bearer (caterpillar)
Synonyms and other taxonomic changes
Nematocampa resistaria (Herrich-Schäffer, )
Nematocampa limbata (formerly lumped with this Eurasian species)
Ferguson (1993) revised the NA species of Nematocampa and was the author who revised the status of the species commonly called N. limbata to N. resistaria.
Yellowish with distinctive pattern--see photo. Note especially the single am line and the double pm line--the latter far apart at costa, almost touching below it, then separating again. Dark coloration beyond pm line variably purple to brown (1)
A dimorphic species, both between sexes (sexual dimorphism) and within the males; dimorphism in females rare.
Ferguson (1993) describes this species as follows “This widespread nearctic species is distinguished by the whitish ground color of nearly all females (with rare exceptions) to the more yellowish males.” BugGuide image #40816 is a female:
Males vary from having dark blotches--images in Covell (1)
and BugGuide images below, showing some of the variability,
to having none - described by Ferguson as “brown markings well developed to obsolescent”. Such markings are geographically variable that has led to them being named as separate subspecies and species.
Strange! Eversible tentacles extend from the dorsal surface of A2 and A3. In the first photo (below, left) they are in the 'relaxed' condition; when the caterpillar is alarmed these tentacles can be extended to 2x their resting length (below, right). These same structures probably occur in other species in the genus; but otherwise I believe they may be unique.
Includes eastern North America. Listed as local and uncommon (1)
. Reasonably common in NB, seen every year in Fredericton. Also found in Eurasia, depending on taxonomic treatment (see Remarks).
Nova Scotia to Vancouver Island, south to Florida and west to Texas and Colorado. Utah and Oregon but not California. The California species is N. brehmeata(2)
Deciduous forests and coniferous forests.
May-August, April in deep south
Larvae feed on many hardwoods and several softwood species of shrubs and trees including
pine, hemlock, fir, larch and spruce(2)
One generation in north, double brooded in middle states; more than double brooded in south.
which is very similar, but is restricted to central and northern Califonia west of the Sierra Nevada.
Covell, p. 373, plate 54 #12--listed as N. limbata (1)
Ferguson,D.C. 1993. A revision of the species of Nematocampa
(Geometridae; Ennominae) occurring in the United States and Canada. J. Lep. Soc 47(1):60-77. (3)
Miller, p. 54, #75--N. resistaria (4)
Wagner, p. 194--photo of caterpillar and adult specimen (5)