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Species Macaria pustularia - Lesser Maple Spanworm - Hodges#6273

Lesser Maple Spanworm? - Macaria pustularia Lesser Maple Spanworm Moth - Hodges#6273 - Macaria pustularia - male Speranza pustularia - Macaria pustularia - male Speranza pustularia - Hodges #6273 - Macaria pustularia Lesser Maple Spanworm - Macaria pustularia MothWhitewithBrwnCostalMarks07082017_GH_ - Macaria pustularia Lesser Maple Spanworm Moth - Macaria pustularia Lépidoptère, famille Geometridae - Macaria pustularia - Macaria pustularia - male
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Geometroidea (Geometrid and Swallowtail Moths)
Family Geometridae (Geometrid Moths)
Subfamily Ennominae
Tribe Macariini
Genus Macaria
Species pustularia (Lesser Maple Spanworm - Hodges#6273)
Hodges Number
Synonyms and other taxonomic changes
Speranza pustularia (Guenée, [1858])
Itame pustularia
Macaria pustularia
Explanation of Names
PUSTULARIA: from the Latin "pustulare" (to blister); the third orangish-yellow marking along the forewing costa [representing the top of the PM line] is reminiscent of a pustule that has broken and leaked a trail of pus down the wing - not a very nice mental image, but a good way to remember this species
may be locally abundant; numbers may vary considerably from year to year
wingspan 18-27 mm
fullgrown larva average length 20 mm
Adult: forewing pure white with sharp orangish-yellow to brown markings (heaviest as tops of four lines at costa); PM line usually most complete line, and continues onto hindwing; in some individuals, only the markings along the forewing costa are visible
[adapted from description by Charles Covell]
labial palps beak-like, projecting forward beyond eyes

Larva: head green; body green with contrasting narrow white, cream, or yellowish lines
Nova Scotia to Florida, west to Mississippi, north to North Dakota and Saskatchewan (but apparently missing from Manitoba)
deciduous and mixed woods; adults are nocturnal and attracted to light
adults fly from May to July in the south; June to August in the north (Quebec)
larvae in May and June
larvae feed mainly on leaves of maple (especially Red Maple [Acer rubrum]) but have also been recorded on birch, cherry, poplar, fir (Abies spp.), hemlock (Tsuga spp.), and tamarack
Life Cycle
one generation per year; overwinters as an egg; gray or pink eggs are laid singly on branches and trunk of host trees; larvae hatch in May and early June; pupation begins in late June or early July and usually lasts about 10 days
[adapted from text at Canadian Forest Service]
Many former species of Itame and Semiothisa were transferred to the genus Macaria in Malcolm Scoble's catalog, Geometrid Moths of the World (1999) - see genus page
See Also
No other pure white moth has four orangish-yellow markings along the forewing costa.
Print References
Ferguson, D.C., 2008. The Moths of America North of Mexico, Fascicle 17.2 The Wedge Entomological Research Foundation. p. 138; pl. 3, figs. 22-27.(1)
Internet References
live adult image (Charles Lewallen, Oklahoma)
live adult images (Lynn Scott, Ontario)
distribution in Canada list of provinces (CBIF)
Works Cited
1.The Moths of America North of Mexico, Fascicle 17.2, Geometroidea, Geometridae, Ennominae.
Douglas C. Ferguson . 2008. The Wedge Entomological Research Foundation.
2.North American Moth Photographers Group