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Species Ennomos subsignaria - Elm Spanworm - Hodges#6798

Elm Spanworm, top - Ennomos subsignaria - male white and green moth - Ennomos subsignaria Moth with Tall Antennae - Ennomos subsignaria - male Elm Spanworm - Ennomos subsignaria - male Ennomos subsignaria - Elm Spanworm - Ennomos subsignaria - male 1303787,8 moth - Ennomos subsignaria - male Lepidoptera  - Ennomos subsignaria - male Ennomos subsignaria - male
Show images of: caterpillars · adults · both
Classification
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 Ennomini
Genus Ennomos
Species subsignaria (Elm Spanworm - Hodges#6798)
Hodges Number
6798
Synonyms and other taxonomic changes
Ennomos subsignaria (Hübner, [1823])
Ennomos niveosericeatus (Harris, 1855)
Eudalimia subsignaria Hübner, 1823
Phylogenetic sequence # 911229
Size
wingspan in the 35-40 mm range (BG images)
Identification
"Pure white except for yellow branches on bipectinate antennae. [of the males] Easily separated from other all-white species by angled outer margin of FW."
[description by Charles Covell (1)]

Some individuals have a significant amount of green coloring on the wings and legs and sometimes part of the antennae:
Range
from Texas to Alberta and east to the Atlantic
Season
adults fly in July and August, earlier (late April-June) in Texas and southern states
larvae present from May to July
Food
Larvae feed on elm, apple, birch, maple, and oak
Life Cycle
One generation a year
Overwinter as eggs(2)
Young larvae feed on the lower surfaces of leaves, producing shot-hole effects. Older ones eat the entire leaf except the midrib and petiole. When ready to pupate, they spin coarse, net-like cocoons of silken threads often on partially eaten leaves.(2)

Eggs, larva, larva, pupa, adult male, adult female:
Remarks
Telenomous alsophilae is a parasite.(2)
Calosoma scrutator will voraciously consume the larvae(2)
See Also
Eugonobapta nivosaria - Snowy Geometer - Hodges#6965
Shape of forewing is different.
Internet References
adult images (Larry Line, Maryland)
several images and biology info (Pennsylvania State U.)
live larva image (forestpests.org)
common name reference and other info (Ohio State U.)
Works Cited
1.Field Guide to Moths of Eastern North America
Charles V. Covell, Jr. 2005.
2.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.