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

Moth - owlet? - Malacosoma americana Eastern Tent Caterpillar Moth - Hodges #7701 - Malacosoma americana - male Eastern Tent Caterpillar Moth - Hodges #7701 - Malacosoma americana - male Eastern Tent Moth - Hodges #7702 - Malacosoma americana Eastern tent caterpillar moth - Malacosoma americana Lasiocampidae, Eastern Tent Caterpillar Moth - Malacosoma americana - male Malacosoma americana moth 043016 - Malacosoma americana
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 americana (Eastern Tent Caterpillar Moth - Hodges#7701)
Hodges Number
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
one of 6 species in this genus in North America common
wingspan 22-44 mm (5)
Caterpillar length to 57 mm (2¼ in) (6)
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.
Eastern and central US to the Rockies (6) and Canada from Nova Scotia to Alberta
Tents appear in early spring, and caterpillars are seen until early summer (7).
On Block Island, RI, adults fly throughout June and July, peaking in abundance in early July.(8)
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. of larvae 2.Cocoon 3.Pupa 4.Adult female 5.Adult male

one generation per year; overwinters as an egg
A good overview of larval habits (shelter building, feeding, thermoregulation, anti-predator defense, trail making and recruitment) appears on this page by Terrence Fitzgerald.
Most of the hosts of this caterpillar have little value so it doesn't contribute to economic losses.(9)
A parasitoid that attacks this moth is Itoplectis conquisitor. This ichneumon is attracted by the scents from flowering plants in orchards, but only when nectar is available.(10)

Telemonus clisiocampanae, a wasp in the Scelionidae family, parasitizes the eggs(9)
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 (11)
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.Block Island Moths
9.Eastern Forest Insects
Whiteford L. Baker. 1972. U.S. Department of Agriculture · Forest Service.
10.Insect Ecology: Behavior, Populations and Communities
P. W. Price, R. F. Denno, M. D. Eubanks. 2011. Cambridge University Press.
11.Caterpillars of Eastern North America
David L. Wagner. 2005. Princeton University Press.