American Grannom vs Two-toothed Goldenring
Side-by-side species comparison
| Attribute | American Grannom | Two-toothed Goldenring |
|---|---|---|
| Scientific Name | Brachycentrus americanus | Cordulegaster bidentata |
| Order | Trichoptera | Odonata |
| Family | Brachycentridae | Cordulegastridae |
| Size | 9-13 mm | 70-80 mm |
| Habitat | Rivers & Streams | Mountains |
| Diet | Omnivores | Omnivores |
| Regions | North America | Europe |
| Conservation | Least Concern | Near Threatened |
American Grannom
A case-building caddisfly whose larvae attach their cases to rocks in fast current and filter-feed. Cases are chimney-shaped and built from silk and plant fragments.
Did You Know?
Larvae can switch between filter-feeding and scraping algae depending on current speed.
Two-toothed Goldenring
A large, dark goldenring dragonfly of central European mountain streams. It is distinguished from other goldenrings by two tooth-like projections on the occipital triangle.
Did You Know?
Its larvae develop in tiny trickles of spring water no wider than a hand, unlike most large dragonflies.