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Species Megalopyge opercularis - Southern Flannel Moth - Hodges#4647

Flannel Moth - Megalopyge opercularis Southern Flannel Moth - Megalopyge opercularis - male PLEASE ID this. It is about 1 inch long and 3/4 wide, has fur and suction cup feet. - Megalopyge opercularis Moth - Megalopyge opercularis - male Southern Flannel Moth - Hodges#4647 - Megalopyge opercularis Megalope opercularis? - Megalopyge opercularis Megalopyge opercularis - male Florida Moth - Megalopyge opercularis - 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 Zygaenoidea (Flannel, Slug Caterpillar, Leaf Skeletonizer Moths and kin)
Family Megalopygidae (Flannel Moths)
Genus Megalopyge
Species opercularis (Southern Flannel Moth - Hodges#4647)
Hodges Number
Other Common Names
Puss Caterpillar, Asp, "gusano-pollo" & "perrito" (Spanish)
Synonyms and other taxonomic changes
Megalopyge opercularis (J.E. Smith)
Phalaena opercularis J.E. Smith 1797 (1)
Megalopyge bissesa Dyar, 1911
Phylogenetic sequence #140625
Explanation of Names
Puss Caterpillar refers to cat-like form of caterpillar, perhaps. Asp refers to sting of caterpillar, is a local name used in Texas (2).
Wingspan 24-36 mm.
Larvae to 30 mm.
Note orange thorax and base of forewings. Sexually dimorphic.
Female (thread-like antennae) has weak markings, though is still yellowish:

Male (feathery antennae) has stronger markings:

Caterpillar is densely covered with gray to tan hairs, which form a rusty-red crest along the back. Unlike the similar Lagoa crispata (Megalopyge crispata), it has a tail-like tuft of hairs that stick straight out from the rear end, extending for a length greater than two body segments. (2):
se US to NJ, also se AZ - Map (MPG)
Deciduous forests and adjacent areas
mostly: May-Oct; all year in TX, FL (MPG data)
Larvae are polyphagous (Heppner 1997) and are recorded from plant species belonging to 41 genera (3). Some host records may be erroneous.
In north central Florida, puss caterpillars are most common on various species of oaks but are also common on elms. - UFL
In Arizona, the known larval hosts of M. o. bissesa include Quercus oblongifolia (Mexican blue oak) and Arctostaphylos sp. (manzanita).
Life Cycle
larval development takes about six weeks (Micks 1956)
Caution, caterpillars have painful sting.
Occasionally, in outbreak years, puss caterpillars are sufficiently numerous to defoliate some trees (Bishopp 1923). However, their main importance is medical. In Texas, they have been so numerous in some years that schools in San Antonio in 1923 and Galveston in 1951 were closed temporarily because of stings to children (Diaz JH. 2005. The evolving global epidemiology, syndromic classification, management, and prevention of caterpillar envenoming. American Journal of Tropical Medicine and Hygiene 72: 347-357)
See Also
Black-waved Flannel Moth - Megalopyge (Lagoa) crispata
- Range: e. US
Print References
Smith, J.E. & J. Abbot, 1797. The natural history of the rarer lepidopterous insects of Georgia. J. Edwards, Cadell & Davies, and J. White, London., vol. 2: 105; Pl.53. (1)
Dyar, H.G., 1911. Descriptions of new species and genera of Lepidoptera from Mexico. Proceedings of the United States National Museum, 38: 267.
Bishopp FC. 1923. The puss caterpillar and the effects of its sting on man. United States Department of Agriculture. Department Circular 288. 14 pp.
Davidson FF. 1967. Biology of laboratory-reared Megalopyge opercularis Sm. & Abb. Morphology and histology of the stinging mechanism. Texas Journal of Science 19(3): 258-274.
Diaz JH. 2005. The evolving global epidemiology, syndromic classification, management, and prevention of caterpillar envenoming. American Journal of Tropical Medicine and Hygiene 72: 347-357.
Heppner JB. 1997. Urticating caterpillars in Florida: 3. Puss caterpillar and flannel moths (Lepidoptera: Megalopygidae). Florida Department of Agriculture and Consumer Services, Division of Plant Industry. Gainesville, Florida. Entomology Circular No. 381. 2 pp.
Micks DW. 1956. Laboratory rearing of the puss caterpillar, with notes on the incidence of parasitism. Journal of Economic Entomology 49: 37-39.
Powell, J. A. & P. A. Opler, 2009. Moths of Western North America. University of California Press. plate 20, fig. 24; p.165. (4)
Wagner, p. 55--photo of larva (two different instars), adult (2)
Covell p. 412, plate 56 #12 (5)
Internet References
Moth Photographers Group - range map, photos of living and pinned adults.
Featured Creatures - Donald W. Hall, University of Florida, 2013
Asps and Other Stinging Caterpillars - Texas AgriLife Extension Service
BOLD - Barcode of Life Data Systems - species account with collection map and photos of pinned adults.
Works Cited
1.The Natural History of the Rarer Lepidopterous Insects of Georgia.
James Edward Smith & John Abbot. 1797. J. Edwards, Cadell & Davies, and J. White, London. 2 vols., 214 pp., 104 pl. .
2.Caterpillars of Eastern North America
David L. Wagner. 2005. Princeton University Press.
3.Arthropods of Florida and Neighboring Land Areas: Lepidoptera of Florida
J.B. Heppner. 2003. Florida Department of Agriculture 17(1): 1-670.
4.Moths of Western North America
Powell and Opler. 2009. UC Press.
5.Peterson Field Guides: Eastern Moths
Charles V. Covell. 1984. Houghton Mifflin Company.