Putting a Name to a Face

On my last fishing trip to the North Ram River I collected two adult stoneflies (Plecoptera: Capniidae) from the snow along the river (see blog post from 25-Oct-2011). I finally had a chance to identify the specimens and although they are both females, their characteristics are consistent with Bolshecapnia gregsoni. While knowing the exact species name will not add anything new to how one would fish this minor hatch (most members of the family Capniidae are similar in appearance and behavior), it does potentially add another piece to the entomological puzzle.

Capniidae – tentatively identified as Bolshecapnia gregsoni

According to Stewart and Oswood (2006) this particular species is endemic to British Columbia, having only been collected from a small handful of locations across southern BC. The nymphs have not yet been described and virtually nothing is known of the biology of this species, although there are hints that this species may be one of the few stoneflies that inhabit lakes. This leaves me with a few questions to be worked out before I can definitively say that the know range of this species can be extended to Alberta: It is remotely possible that the few adults I saw could have been carried into the Ram River drainage by a freak weather event that carried them over the Rockies. There is also a chance that these specimens may not have hatched from the river but instead may have come from a still water habitat nearby. And finally there is the possibility that the specimens are not Bolshecapnia gregsoni – while the female characteristics can be used for species identification in some stoneflies (including Bolshecapnia) it is the male genitalia that usually provide definitive proof.

 All of this is part of why I find the study of aquatic entomology so interesting. Given all that we know, we are still only scratching the surface – there are many species yet to be discovered and of those that are known, their full range and biology are often shrouded in mystery. There is ample opportunity for professional and amateur entomologists alike to add small bits of information to our collective knowledge; another piece of the puzzle – a puzzle so immense and complex that it will never really be finished. It is this tantalizing hint of a mystery to be solved that excites me. I will be out on the North Ram next fall with the goal of collecting more Bolshecapnia adults (and hopefully some males); and with any luck, I will add another piece to the entomological puzzle.

Stewart, K. W. and M. S. Oswood. 2006. The Stoneflies (Plecoptera) of Alaska and Western Canada. The Caddis Press, Columbus, Ohio. 325pp.