Grannom Caddisfly vs Eastern Weighted Casemaker

Side-by-side species comparison

Attribute Grannom Caddisfly Eastern Weighted Casemaker
Scientific Name Brachycentrus subnubilus Goera stylata
Order Trichoptera Trichoptera
Family Brachycentridae Goeridae
Size 8-12 mm 8-12 mm
Habitat Rivers & Streams Rivers & Streams
Diet Detritivores Omnivores
Regions Europe Europe
Conservation Least Concern Least Concern

Grannom Caddisfly

A small dark caddisfly that produces massive spring hatches on European rivers. Larvae build distinctive square-sectioned cases from silk and plant fibers.

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Did You Know?

Grannom hatches are so dense on some rivers that local people historically swept up mounds of dead adults to use as fertilizer.

Eastern Weighted Casemaker

A caddisfly of clean European streams that builds mineral cases with large lateral ballast stones. Larvae scrape algae from rock surfaces in moderate current.

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Did You Know?

The lateral ballast stones are so precisely placed they appear to be glued on by hand.