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Species Malacosoma disstria - Forest Tent Caterpillar Moth - Hodges#7698

Forest Tent Caterpillar - Malacosoma disstria Eastern Tent Caterpillar? - Malacosoma disstria Forest Tent Caterpillar - Malacosoma disstria - male Malacosoma disstria caterpillar - Malacosoma disstria Malacosoma disstria Forest Tent Caterpillar - Malacosoma disstria Moth sp - Malacosoma disstria Forest Tent Caterpillar Moth - Malacosoma disstria 5/21/17 moth - Malacosoma disstria
Show images of: caterpillars · adults · both
Kingdom Animalia (Animals)
Phylum Arthropoda (Arthropods)
Subphylum Hexapoda (Hexapods)
Class Insecta (Insects)
Order Lepidoptera (Butterflies and Moths)
Superfamily Lasiocampoidea (Tent Caterpillar and Lappet Moths)
Family Lasiocampidae (Tent Caterpillar and Lappet Moths)
Subfamily Lasiocampinae
Tribe Lasiocampini
Genus Malacosoma
Species disstria (Forest Tent Caterpillar Moth - Hodges#7698)
Hodges Number
Explanation of Names
Malacosoma disstria Hübner, 1820
wingspan 25-45 mm
larvae length to 64 mm
Adult: stout-bodied; forewing light brown with two darker, thin parallel lines extending across mid-portion, the area between often being dark and appearing as a single broad, dark band
Larvae: dark-gray to brownish-black background body color, highlighted by broad, pale-blue lines and thin, broken yellow lines extending along each side; dorsum of each abdominal segment has distinct whitish keyhole or shoeprint-shaped marking; body has fine, whitish, and sparsely distributed hairs
widely dist., but more common east of Mississippi River - Map (MPG)
on or near host tree species
Adults mostly fly from April to August (MPG)
Caterpillars typically April-June.
larvae feed on leaves of alder, basswood, birch, cherry, oak, poplar, willow
Life Cycle
One generation per year; larvae spin silken mats on tree trunks and large branches where they congregate to molt or rest from feeding; larvae also deposit silk in strands along which they travel to and from feeding sites; overwinters as larva in masses surrounding tree branches. (Unlike Eastern Tent Caterpillar, this species does not form silken tents.)
In Canada, some outbreaks of this pest have persisted for 6 years and have been extremely widespread. In 1962 over 139,000 square miles of defoliation occurred in the four western provinces. However, reduced growth and some branch killing are the usually extent of damage. - UBC

The species name disstria is a simple noun, so does not follow the genus name in gender.
(Malacosoma is neuter, so adjectivic species names end -um instead of -a. (1))
See Also
Eastern Tent Caterpillar (Malacosoma americanum) has an unbroken cream/white line along its back, and a dark face.

The adult Malacosoma americanum have light colored transverse lines
Print References
Covell, p. 54, plate 11#3 (2)
Wagner, p. 227--photo of caterpillar, specimen of adult (3)
Internet References
Moth Photographers Group - range map, photos of living and pinned adults.
Featured Creatures - James R. Meeker, Florida Department of Agriculture
Works Cited
1.A revision of the genus Malacosoma (Hubner) in North America (Lepidoptera: Lasiocampidae): systematics, ...
Frederick W. Stehr; Edwin F.Cook . 1968. Bulletin of the United States National Museum, 276: 1-321.
2.Peterson Field Guides: Eastern Moths
Charles V. Covell. 1984. Houghton Mifflin Company.
3.Caterpillars of Eastern North America
David L. Wagner. 2005. Princeton University Press.