Species Insects & ArthropodsAlderfly

Alderfly

Sialis lutaria

CommonInsect & Arthropod
Illustration of Alderfly (Sialis lutaria)

The Alderfly is a small, dark, soft-winged insect with strongly veined wings held tent-like over the body, commonly found resting on streamside vegetation in spring. Larvae are aquatic predators in stream and pond sediment for 1–2 years before emerging to pupate in soil. Adults are short-lived and do not feed, concentrating entirely on reproduction near the water where they developed.

Habitat
Streamside vegetation, pond edges, and woodland near clean water
Diet
Larvae: aquatic invertebrates. Adults: do not feed
How common
Common

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