Very nice, Mark.
Thanks, Roger. Any idea as to species?
Although you will probably need to capture an adult in order to make a species level identification, Aquatic Insects Of California does has species level keys under the earlier genus name of Parargyractis.
Amazing. Are those some type of gill filaments around spiracles?
Probably of no interest except for the bug geeks on the site but apparently if you find Petrophila larvae you have a chance of finding an aquatic Hymenoptera parasite as well. Paper on it is here http://biostor.org/cache/pdf/05/10/a7/0510a77977bda72401f5a277cf4fa2ac.pdf.
Ok, now go find us a parasitized one! ;)
Nice. Vince R. Is right, you never hear about aquatic icneumonids or any aquatic Hymenoptera. Ok, now go find us a parasitized one! ;)