Malagasy Dobsonfly vs Japanese Alderfly

Side-by-side species comparison

Attribute Malagasy Dobsonfly Japanese Alderfly
Scientific Name Neochauliodes madagascariensis Sialis japonica
Order Megaloptera Megaloptera
Family Corydalidae Sialidae
Size 40-60 mm wingspan 15-25 mm wingspan
Habitat Rivers & Streams Rivers & Streams
Diet Predators Predators
Regions Madagascar Japan, East Asia
Conservation Data Deficient Least Concern

Malagasy Dobsonfly

A large, brown-winged insect with broad wings held tent-like over the body at rest. Males may have elongated mandibles. Larvae are aquatic and known as hellgrammites.

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Did You Know?

The aquatic larvae are considered indicators of clean water quality, as they cannot tolerate polluted streams.

Japanese Alderfly

A medium-sized alderfly found in ponds and slow streams across Japan. It is one of the most common megalopterans in East Asian lowland waters.

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Did You Know?

It is one of the few megalopterans adapted to living in rice paddy fields.