Water Quality ID

[waywardwind12]

Nope

[caseyotis]

I got it (Click to Show Hidden Text)

Riffle Beetle Larva?

[waywardwind12]

Correct!

[caseyotis]

ID (Click to Show Hidden Text)

[img]http://somethingscrawlinginmyhair.com/wp-content/uploads/2009/05/giantwaterbugeatinggoldfish.jpg[/img]

[cupcakegirl]

Not positive, but I think it is (Click to Show Hidden Text)

Giant Water Bug

[Blwrunner]

Yes I agree. But can someone please help me tell the difference between the giant water bug and the water scorpion.

[caseyotis]

That is correct.

Yes I agree. But can someone please help me tell the difference between the giant water bug and the water scorpion.

Besides the obvious difference in the larvae, the adult forms are fairly simple to differentiate between. First of all, if there's a picture of eggs on the thing's back, it's a giant water bug. The legs of a water scorpion are thinner, and the front pincer-things are more... Extended from the face. I don't know how to put it exactly, but if you take a look here:

This picture (Click to Show Hidden Text)

[img]http://australianmuseum.net.au/Uploads/Images/4076/Giant%20Water%20Bug2_big.jpg[/img]

and

this one (Click to Show Hidden Text)

[img]http://www.hainaultforest.co.uk/PondWaterScorpion.jpg[/img]

You can see the difference. Which one is which should be easy to tell.
Also, the water scorpion has a strange appendage that extends from its thorax and is like a straight line; the larvae have this as well, I believe.

[Blwrunner]

Okay thanks! You can post a picture now

[caseyotis]

It's cupcakegirl's turn.

[cupcakegirl]

How about (Click to Show Hidden Text)

[img]http://geoffpark.files.wordpress.com/2011/02/water-scorpion.jpg[/img]