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Species Malacosoma americana - Eastern Tent Caterpillar Moth - Hodges#7701

Eastern Tent Caterpillars - Malacosoma americana Eastern Tent Caterpillar - Malacosoma americana Furry 2-Lined Moth - Malacosoma americana - male Caterpillar - Malacosoma americana A blue, black, and gold web worm - Malacosoma americana Caterpillar - Malacosoma americana Moth - Malacosoma americana Malacosoma ? - Malacosoma americana
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 Lasiocampoidea (Tent Caterpillar and Lappet Moths)
Family Lasiocampidae (Tent Caterpillar and Lappet Moths)
Subfamily Lasiocampinae
Tribe Lasiocampini
Genus Malacosoma
Species americana (Eastern Tent Caterpillar Moth - Hodges#7701)
Hodges Number
7701
Other Common Names
Eastern Tent Caterpillar (larva)
Synonyms and other taxonomic changes
Malacosoma americana (Fabricius, 1793)
Bombyx americana Fabricius, 1793
Explanation of Names
The gender of Malacosoma is neuter, so adjectivic species names ending -a are considered wrong spellings.(1) Following the Code of Zoological Nomenclature, the correct combination would be Malacosoma americanum (Fabricius, 1793).
The 2018 Canada & AK Checklist uses original spelling for species-level names following the practice "... by most lepidopterists in leading catalogues and checklists, as discussed by Sommerer (2002) and formally adopted by the Societas Europaea Lepidopterologica."(2)(3) For further justification see Nieukerken et al. (2019).(4) - Steve Nanz - 10/29/2019
Numbers
one of 6 species in this genus in North America common
Size
wingspan 22-44 mm (5)
Caterpillar length to 57 mm (2¼ in) (6)
Identification
Adult: body and wings warm fawn brown; forewing with white AM and PM lines; median area sometimes white (5)
wings of male are darker and more brownish; wings of female are paler and more yellowish

Larva: distinguished by a solid cream/white line along the dorsum (middle of the back). Sides of the body are marked with blue, black, orange and white. Dark face.
Range
Eastern and central US to the Rockies (6) and Canada from Nova Scotia to Alberta
Season
Tents appear in early spring, and caterpillars are seen until early summer (7).
Moths fly from late May to June (5).
Food
larvae feed on leaves of many trees and shrubs but particularly members of the rose family such as apple, cherry, and crabapple (5)
Life Cycle
Female deposits egg mass on twig where it overwinters (6).

Larvae emerge in spring and begin building their tent which they continue to expand as they grow.

Fully grown caterpillars eventually disperse and find a place to pupate.
1.group of larvae 2.Cocoon 3.Pupa 4.Adult female 5.Adult male

one generation per year; overwinters as an egg
Remarks
A good overview of larval habits (shelter building, feeding, thermoregulation, anti-predator defense, trail making and recruitment) appears on this page by Terrence Fitzgerald.
See Also
Malacosoma disstria forewing has dark AM and PM lines. The median area is often darker than the remainder of the forewing.


Malacosoma californicum is slightly smaller but otherwise similar and probably indistinguishable from M. americanum in areas where their ranges overlap.

compare photos of all 3 species at CBIF
-
Larva of Forest Tent Caterpillar (Malacosoma disstria) has a broken dorsal line forming keyhole or footprint shapes along its back, and generally more blue on its body, including the face. Larvae form silken mats where they congregate, not tents.

Print References
Fabricius, 1793. Ent. Syst. 3(1): 433
Stehr, F.W. & E.F. Cook 1968. A revision of the genus Malacosoma Hübner in North America (Lepidoptera: Lasiocampidae): systematics, biology. immatures, and parasites. Bulletin of the United States National Museum. 276: 1-321. (1)
Wagner, p.226 (8)
Internet References
distribution in Canada list of provinces (CBIF)
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.Annotated checklist of the moths and butterflies (Lepidoptera) of Canada and Alaska
Pohl, et al. 2018. Pensoft, 580 pages.
3.To agree or not to agree - the question of gender agreement in the International Code of Zoological Nomenclature
Sommerer, M.D. 2002. Nota Lepidopterologica, 25(2/3): 191-20.
4.Stability in Lepidoptera names is not served by reversal to gender agreement: a response to Wiemers et al. (2018)
Van Nieukerken, E.J., O. Karsholt, A. Hausmann, J.D. Holloway, P. Huemer, I.J. Kitching, M. Nuss, G.R. Pohl, H. Rajaei, E. Rennl. 2019. Nota Lepidopterologica, 42(1): 101-111.
5.Field Guide to Moths of Eastern North America
Charles V. Covell, Jr. 2005.
6.Peterson First Guide to Caterpillars of North America
Amy Bartlett Wright. 1998. Houghton Mifflin Company.
7.Caterpillars of Eastern Forests
David L. Wagner, Valerie Giles, Richard C. Reardon, Michael L. McManus. 1998. U.S. Dept of Agriculture, Forest Health Technology Enterprise Team.
8.Caterpillars of Eastern North America
David L. Wagner. 2005. Princeton University Press.