Southern Flannel Moth vs Mountain Prosimulium

Side-by-side species comparison

Attribute Southern Flannel Moth Mountain Prosimulium
Scientific Name Megalopyge opercularis Prosimulium mixtum
Order Lepidoptera Diptera
Family Megalopygidae Simuliidae
Size 25-36 mm wingspan 2-4 mm
Habitat Woodlands Mountains
Diet Omnivores Omnivores
Regions Southeastern United States, Central America North America
Conservation Least Concern Least Concern

Southern Flannel Moth

A fluffy moth covered in cream to orange-brown fur-like scales. Its larva, called the puss caterpillar, is covered in soft-looking hair that conceals venomous spines.

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Did You Know?

The puss caterpillar is considered the most venomous caterpillar in North America, with stings requiring medical attention.

Mountain Prosimulium

An early-season black fly of cold mountain streams in North America. Larvae develop in small headwater streams during late winter and early spring.

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Did You Know?

Adults emerge so early in spring that they are often the first biting flies encountered by hikers each year.