The family Sialidae contains the neuropterous insects known as alderflies. They are closely related to the dobsonflies, and have long filamentous antennae and four large wings, of which the anterior pair is slightly longer than the posterior. There is only one genus, Sialis, in North America and Europe, and a few other small genera elsewhere (Japan, South America).

The females lay a vast number of eggs upon grass stems near water. The larvae are aquatic, active, armed with strong sharp mandibles, and breathe by means of seven pairs of abdominal branchial filaments. When full sized they leave the water and spend a quiescent pupal stage on the land before metamorphosis into the sexually mature insect.

Sialis lutaria is the commonest alderfly in the United Kingdom  and across much of Europe.

Image:Sialis lutaria larva (aka).jpg|Sialis lutaria larva Image:Megaloptera-sialidae-sp.gif|Sialoide sp.

External links

• BugGuide
• Insects of Cedar Creek

References