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Species Acharia stimulea - Saddleback Caterpillar Moth - Hodges#4700

Saddleback larva - Acharia stimulea Saddleback caterpillar moth - Acharia stimulea Caterpillar  - Acharia stimulea Kansas Saddleback? - Acharia stimulea Hatched! - Acharia stimulea Saddleback Caterpillar Moth - Acharia stimulea Acharia stimulea; Saddleback moth caterpillar - Acharia stimulea mystery(?) spots - Acharia stimulea
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 Limacodidae (Slug Caterpillar Moths)
Genus Acharia
Species stimulea (Saddleback Caterpillar Moth - Hodges#4700)
Hodges Number
Synonyms and other taxonomic changes
formerly Sibine stimulea
Caterpillar more commonly encountered than the moth
Caterpillar grows to 25mm (1)
Wingspan 26-43mm (2)
Caterpillar has a distinctive green saddle on a black to brown base. The saddle has a central brown patch and is bordered with white. Lobes on the front and rear bear stinging spines. Clusters of spines also line the sides.

Moth dark brown with wings shaded in black and charcoal. Forewing with one white dot near base and a few near the apex.

The male moth (below) has a flared abdomen:
Massachusetts south to Florida and west to eastern Missouri and Texas (2). Also found in Mexico and Central America, and possibly in Colombia.
Caterpillar seen July to October (3)
Moth flies June to August in the North stretching to almost the entire year in the extreme South (4)
Many trees, shrubs, and grasses including apple, asters, blueberries, citrus, corn, dogwoods, elms, grapes, linden, maples, oaks, Prunus species, sunflowers and viburnums (2). Troy has personally seen them feeding on liriope, cherry, oak, and holly.
Life Cycle
Young instar caterpillars are somewhat gregarious.
Formerly Sibine stimulea.
Caterpillars are capable of inflicting lasting and painful stings with their spines.
Internet References
Caterpillars of Eastern Forests - Photo and info on the caterpillar
Ohio State University Extension, University of Vermont Extension, and University of Florida Extension describe various stinging caterpillars including this one and provide treatment information.
Naturalista. Oruga ensillada (Acharia stimulea)
Works Cited
1.Peterson First Guide to Caterpillars of North America
Amy Bartlett Wright. 1998. Houghton Mifflin Company.
2.Peterson Field Guides: Eastern Moths
Charles V. Covell. 1984. Houghton Mifflin Company.
3.Caterpillars of Eastern Forests
4.American Insects: A Handbook of the Insects of America North of Mexico
Ross H. Arnett. 2000. CRC Press.