Rock Caddisfly vs Grannom Caddisfly

Side-by-side species comparison

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

Rock Caddisfly

A caddisfly of limestone streams whose cases incorporate calcareous sand grains and pebble ballast. Larvae scrape algae from rock surfaces.

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Did You Know?

The calcareous case material provides partial camouflage against the pale limestone streambed.

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.