Smoky Alderfly vs Japanese Dobsonfly
Side-by-side species comparison
| Attribute | Smoky Alderfly | Japanese Dobsonfly |
|---|---|---|
| Scientific Name | Sialis fuliginosa | Protohermes grandis |
| Order | Megaloptera | Megaloptera |
| Family | Sialidae | Corydalidae |
| Size | 12-16 mm | 40-60 mm body length |
| Habitat | Ponds & Lakes | Rivers & Streams |
| Diet | Omnivores | Predators |
| Regions | Europe | East Asia, Japan |
| Conservation | Least Concern | Least Concern |
Smoky Alderfly
A European alderfly distinguished from S. lutaria by its preference for flowing water rather than still ponds. It has dark smoky wings and a blackish body.
Did You Know?
This alderfly is a reliable indicator of clean running water and is one of the first species to disappear when streams become polluted.
Japanese Dobsonfly
A large aquatic insect known as 'hebi-tonbo' (snake dragonfly) in Japanese. The adult males have elongated, curved mandibles. Larvae called 'magotaro-mushi' are used as fishing bait.
Did You Know?
Dobsonfly larvae are prized as live fishing bait in Japan and are collected from stream rocks by anglers targeting ayu (sweetfish).