About 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.
Did You Know?
It is one of the few megalopterans adapted to living in rice paddy fields.
How to Identify Japanese Alderfly
Japanese Alderfly (Sialis japonica) belongs to the order Megaloptera, family Sialidae. Adults typically measure 15-25 mm wingspan.
Japanese Alderfly Habitat
Japanese Alderfly is found in rivers & streams habitats, particularly across Japan, East Asia. This species has adapted to thrive in its preferred environment, where it can find suitable food sources and shelter.
Japanese Alderfly Diet and Feeding
Japanese Alderfly is a predatory species that actively hunts and feeds on other insects and small invertebrates. As a predator, it helps control populations of pest species and maintains ecological balance.
Where Is Japanese Alderfly Found?
Japanese Alderfly can be found in Japan, East Asia, where it inhabits rivers & streams environments. Its distribution is influenced by climate, food availability, and habitat suitability.
Distribution Map
Where Japanese Alderfly can be found
Is Japanese Alderfly Dangerous?
Japanese Alderfly is generally harmless to humans. It does not bite or sting and poses no significant health risk. Like most insects, it prefers to avoid human contact and will typically flee rather than confront a perceived threat.
Japanese Alderfly Role in Nature
Japanese Alderfly serves as a natural predator, helping to control populations of other insects. Predatory insects are valuable in both natural ecosystems and agriculture, where they reduce the numbers of pest species without the need for chemical pesticides.
Seasonal Activity
Frequently Asked Questions About Japanese Alderfly
What does Japanese Alderfly look like?
The Japanese Alderfly typically measures 15-25 mm wingspan.
Where is Japanese Alderfly found?
The Japanese Alderfly is found in Japan, East Asia and typically inhabits rivers & streams environments.
What does Japanese Alderfly eat?
The Japanese Alderfly is a predator that hunts and feeds on other insects and small invertebrates.
Is Japanese Alderfly dangerous to humans?
The Japanese Alderfly is generally harmless to humans. It does not bite or sting and poses no significant health risk.
What is an interesting fact about Japanese Alderfly?
It is one of the few megalopterans adapted to living in rice paddy fields.
Cite This Page
APA:
InsectDiscover. (2026). Japanese Alderfly (Sialis japonica). Retrieved from https://insectdiscover.com/insect/japanese-alderfly
MLA:
"Japanese Alderfly." InsectDiscover, https://insectdiscover.com/insect/japanese-alderfly.