Hickory Horned Devil vs Autumn Dun

Side-by-side species comparison

Attribute Hickory Horned Devil Autumn Dun
Scientific Name Citheronia regalis Leptophlebia marginata
Order Lepidoptera Ephemeroptera
Family Saturniidae Leptophlebiidae
Size 150 mm (caterpillar), 130-155 mm wingspan (adult) 10-14 mm
Habitat Woodlands Woodlands
Diet Herbivores Detritivores
Regions North America Europe
Conservation Least Concern Least Concern

Hickory Horned Devil

The largest caterpillar in North America at up to 150 mm, with dramatic curved horns and fearsome appearance. Despite looking terrifying, it is completely harmless.

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Did You Know?

Despite being the most terrifying-looking caterpillar in North America with its huge curved horns, the hickory horned devil is completely harmless — it cannot sting or bite.

Autumn Dun

A dark-winged mayfly that emerges in spring despite its common name. Nymphs inhabit slow-flowing sections of woodland streams among leaf litter.

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Did You Know?

Its common name refers to the brownish autumnal color of the adult, not its emergence season.