Alderfly larvae
Sialis spp. · Aquatic life
Out of the water · Photo: りなべる / CC BY
Also called Alderflies, Sialis, Sialids
How to identify Alderfly larvae
- Brown larvae about 1/2 to 1 inch with six legs and strong jaws
- Seven pairs of long, jointed filaments along the sides of the abdomen
- One long, fringed tail at the rear
- Adults are dark, soft bodied flies with wings held tent shaped over the back
Similar species
Dobsonfly and fishfly larvae (hellgrammites) are larger and end in two short prolegs with hooks instead of a single tail. Whirligig beetle larvae also have filaments along the sides but end in four small hooks, not a single tail.
Profile
| Season | Larvae present all year; adults emerge in spring and early summer. |
|---|---|
| Starts | Adults emerge in spring |
| Depth | Bottom mud and debris |
| How it spreads or reproduces | Winged adults fly; eggs laid in masses on plants over water |
| Habitat | Soft mud and leaf litter on the bottom of ponds, lakes, marshes and slow streams. |
Why it matters in a lake
Predators of small insects and worms and a fish food. A sign of a good mix of bottom living invertebrates.
Where it is found
- Idaho: Occasional
- Oregon: Occasional
- Wyoming: Occasional
Classification
| Kingdom | Animalia |
|---|---|
| Phylum | Arthropoda |
| Class | Insecta |
| Order | Megaloptera |
| Family | Sialidae |
| Scientific name | Sialis spp. |
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Caddisfly larvaeNeed a hand?
Found it in your lake?
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