Black Mayfly vs Mahogany Dun
Side-by-side species comparison
| Attribute | Black Mayfly | Mahogany Dun |
|---|---|---|
| Scientific Name | Ephemera danica var. nigra | Isonychia harperi |
| Order | Ephemeroptera | Ephemeroptera |
| Family | Ephemeridae | Isonychiidae |
| Size | 15-25 mm body | 13-17 mm |
| Habitat | Rivers & Streams | Rivers & Streams |
| Diet | Omnivores | Omnivores |
| Regions | Europe | 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.
Did You Know?
The dark form predominates in acidic upland streams while the typical yellow form prefers alkaline lowland rivers.
Mahogany Dun
A large reddish-brown mayfly with impressive filter-feeding forelegs. Nymphs prefer moderate to fast riffles with clean gravel substrates.
Did You Know?
Adults hold their forelegs forward in flight, making them easy to identify on the wing.