What is this insect?

[Mark Melton]

This one was from a river, but they're also found in ponds and lakes. It's about 16 mm long. Give it an order, family, genus and common name.

 

[Shad]

Ephemeroptera Hexagenia limbata, or "Hex?"

 

[Shad]

Oops... 16 mm is considerably smaller than a hex nymph. Maybe a sulphur? The scientific names are all over the place, so I guess you'll have to ask an entomologist (not a guy who calls it a sulphur) on that one....

 

[Mark Melton]

No, it's not an Ephemeroptera.

 

[Shad]

Not a mayfly? Now I'm intrigued but clueless....

 

[Zak]

Looks like a fishfly.

 

[Mark Melton]

Looks like a fishfly.

No, not a fishfly, but you're getting close.

 

[Cabezon]

That looks like an aquatic beetle larva. Look at those jaws!!!
Steve

 

[Smalma]

I agree a beetle larva: maybe a Dobson fly?

 

[Mark Melton]

That looks like an aquatic beetle larva. Look at those jaws!!!
Steve

Not a beetle larva.

I agree a beetle larva: maybe a Dobson fly?

Dobson fly is close.

 

[Smalma]

Then maybe an alderfly larva?

 

[Long_Rod_Silvers]

Then maybe an alderfly larva?

Agreed.

 

[Mark Melton]

Then maybe an alderfly larva?

Bingo! You got it.

Order - Megaloptera
Family - Sialidae
Genus - Sialis
Common name - Alderfly