Black Mayfly vs Spiny Oak Slug Moth

Side-by-side species comparison

Attribute Black Mayfly Spiny Oak Slug Moth
Scientific Name Ephemera danica var. nigra Euclea delphinii
Order Ephemeroptera Lepidoptera
Family Ephemeridae Limacodidae
Size 15-25 mm body 22-30 mm wingspan
Habitat Rivers & Streams Orchards
Diet Omnivores Omnivores
Regions Europe Eastern North America
Conservation Least Concern Least Concern

Black Mayfly

A dark color variant of the common Green Drake mayfly found in some European populations. The dark form is more prevalent in upland, acidic waters. Important for trout feeding.

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Did You Know?

The dark form predominates in acidic upland streams while the typical yellow form prefers alkaline lowland rivers.

Spiny Oak Slug Moth

A small colorful moth with green, brown, and silver-spotted forewings. Its flattened, jewel-like caterpillar is green with red and yellow markings and bears stinging spines.

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Did You Know?

The ornate caterpillar has been called one of the most beautiful in North America despite its painful sting.