March Brown Mayfly vs Light Cahill Mayfly
Side-by-side species comparison
| Attribute | March Brown Mayfly | Light Cahill Mayfly |
|---|---|---|
| Scientific Name | Rhithrogena germanica | Heptagenia solitaria |
| Order | Ephemeroptera | Ephemeroptera |
| Family | Heptageniidae | Heptageniidae |
| Size | 10-14 mm | 9-13 mm |
| Habitat | Rivers & Streams | Rivers & Streams |
| Diet | Omnivores | Omnivores |
| Regions | Europe | North America |
| Conservation | Near Threatened | Least Concern |
March Brown Mayfly
A spring-emerging mayfly with a brownish body and two tails, historically important to European fly fishing. Its flat nymphs cling to rocks in fast water.
Did You Know?
This species has declined significantly in many European rivers due to pollution and is now considered an indicator of water quality.
Light Cahill Mayfly
A pale-colored mayfly highly prized by fly fishers for imitating hatches. Nymphs prefer moderate current over gravel substrates.
Did You Know?
The Light Cahill dry fly pattern, designed to mimic this species, has been used since the 1880s.