Riffle beetles

[Fredrick]

While looking at this website
http://www.stroudcenter.org/schuylkill/index.htm
I noticed that these bugs were in the top five of abundant Macro-invertebrates in almost every stream . Has anyone tied any flies to intimate theses bugs or know of their importance to trout
http://www.stroudcenter.org/schuylkill/sites/site004.htm

 

[blueheron]

I can't be totally sure because no size is given, but they look alot like mealy worms. Favorite of bait fishermen everywhere.

 

[Fredrick]

I'm leaning towards a reddish orange rhyacophila caddis
http://www.flyfishersrepublic.com/entomology/trichoptera/rhyacophila-larva.jpg

 

[littlelehigh]

Nice find and although they appear to look like mealy worms I think they look more like the largest Chironomidae (midges) in that slide.

Quick google search gave me these 2 decent links

http://people.virginia.edu/~sos-iwla/Stream-Study/Catalog/FGRiffleBeetle.HTML


http://www.biokids.umich.edu/critters/Elmidae/


what I found interesting was the adults return to feed in the same areas as the larvae but are difficult to detect.


Makes me wonder how important they are to trout.

The larvae look very much like a crane fly larvae (with the small tails). I don't think you need to do anything special to mimic them a simple walt's worm will do.

 

[gentleshepherd]

Maybe something like these in a different color:

http://globalflyfisher.com/patterns/sharks-caddis-larva/index.php

 

[troutslammer]

yeah they are about a size 22 or 24 , i wouldn't worry about them

 

[Fredrick]

troutslammer wrote:
yeah they are about a size 22 or 24 , i wouldn't worry about them

I have seen them in Valley under rocks in the park and they looked like a size 18 scud hook to me

 

[jayL]

Fred,

I tied some small dubbing on a hook patterns to imitate them after seeing them on that site.

The fish on valley took them in earnest, but they take lots of flies in earnest. I have no idea if they took them for riffle beetles.

 

[MKern]

Why have I never seen these?

But I'm with Jay, how do you know what the fish are taking the flies to represent.
How do we even know if trout take them at all, like water skippers?

A tan/rusty caddis larva would work, IMO.

I'll stick to my PT's though.

I'd bet they are related to Meal Worms. They turn into beetles too.

 

[DGC]

I did some research on these a few years ago. Scwhiebert (who has been known to mistake his bugs) talks about them, but there the larvae are much larger. I toyed with patterns and decided that generic caddis larvae in either yellow or golden brown were close enough, though I was thinking more like # 14 or # 12 grub hook.. As I recall they are said to be very hard shelled with deep ridges. If I've ever seen one in person I didn't know it, whereas I have seen many ryac and net spinner caddis larvae.

The adults seem to be much smaller than the larva, and also spend a great deal of time in the stream. I've never seen one of these, either, just from reading. I have considered sinking a # 20 crowe beetle to copy the adults (and do double duty as a sunken terrestrial), but haven't really followed up.