Swamp Metalmark vs Labrador Minnow Mayfly

Side-by-side species comparison

Attribute Swamp Metalmark Labrador Minnow Mayfly
Scientific Name Calephelis mutica Baetis labradoriensis
Order Lepidoptera Ephemeroptera
Family Riodinidae Baetidae
Size 22-28 mm wingspan 5-8 mm
Habitat Wetlands Rivers & Streams
Diet Omnivores Omnivores
Regions Upper Midwest United States, Great Lakes region North America
Conservation Near Threatened; extremely local Least Concern

Swamp Metalmark

A rare and localized metalmark butterfly of midwestern wetlands with warm rusty-brown wings marked with fine metallic lines. It has very specific habitat requirements.

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Did You Know?

Some populations consist of fewer than 50 individuals, making it one of North America's most vulnerable butterflies.

Labrador Minnow Mayfly

A small mayfly found in cold northern streams with rapid currents. Nymphs cling to submerged stones and feed on periphyton.

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Did You Know?

Nymphs can complete their development in as little as three weeks during warm summer conditions.