Troutnut.com Fly Fishing for Trout Home
User Password
or register.
Scientific name search:

> > Nymph ID please

JOHNW has attached this picture to aid in identification. The message is below.
Shown Full Size
JOHNWMay 12th, 2012, 7:04 am
Chambersburg, PA

Posts: 452
Need help with ID of this nymph. I know picture is not the best quality.
Behavioral note this fellow was a very strong swimmer.
JW
"old habits are hard to kill once you have gray in your beard" -Old Red Barn
WiflyfisherMay 12th, 2012, 12:32 pm
Wisconsin

Posts: 603
Looks sort of like a Siphloplecton or Isonychia nymph too me.
John S.
https://WiFlyFisher.com
EntomanMay 12th, 2012, 1:58 pm
Site Editor
Northern CA & ID

Posts: 2604
Hi John & John,

I agree about the possibility of the first suggestion. It looks like it could be Siphloplecton basale (Pseudo Gray Drake). Isonychia nymphs aren't marked like this, shaped like this, and their gills aren't so prominently tracheated. Also, the forelegs are more prominent and hairy.

Was the underside pale with a thin dark stripe running down the center?
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman
PaulRobertsMay 12th, 2012, 2:49 pm
Colorado

Posts: 1776
Looks a bit like Siphlonurus, but Siphloplecton will have forked claws where the former has a single claw.
EntomanMay 12th, 2012, 4:12 pm
Site Editor
Northern CA & ID

Posts: 2604
Paul,

Looks a bit like Siphlonurus...

Yes, and frankly more than a bit.:) Siphlonurus is certainly another possibility and they are far more common. They can also have noticeable gill tracheation but they (gills) are shaped entirely different than Siphloplecton (heart shaped, much wider at the apex and doubled up) at least on the first few segments. The margins of siphlonurid gills are clearly noticeable with some cloudiness to the membranes, whereas Siphloplecton's are so transparent that in the right lighting they look just like old dead branches waving in the water. The gills in this photo certainly look to be denser in the first couple of segments, signaling Siphlonurus. Like the claws though, they can't really be made out. The heavy tracheation and lack of sclerotized band on the gill margins definitely rules out the similar looking ameletids, so it's between these two...

Looking directly down, Siphlonurus usually has tails approaching abdominal length with the abdomen comprising a little more than two thirds total body length. Siphloplecton on the other hand, will have tails substantially shorter then abdomen length and the abdomen will take up as much as 3/4 total body length. The angle of the photo coupled with the fore lengthening affect of the body parts closest to the lens makes it difficult to tell. It's hard to describe, but the two have distinctly different silhouettes. Here are two examples that John can use to perhaps jog his memory.
Siphloplecton
http://flyfishingentomology.com/forum/Replies_Display.php?t=0049
Siphlonurus
http://www.troutnut.com/specimen/997
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman
CrepuscularMay 12th, 2012, 9:55 pm
Boiling Springs, PA

Posts: 917
John, where did you collect it? Clark's creek perhaps?
EntomanMay 13th, 2012, 1:23 am
Site Editor
Northern CA & ID

Posts: 2604
Eric -
I was hoping you'd chime in. What do you think? No fair waiting for John's response to all the goings on... You're a local for Pete's sake! :)
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman
JOHNWMay 13th, 2012, 1:14 pm
Chambersburg, PA

Posts: 452
Unfortunatly I did not collect the sample nor did I ever see it beyond the picture posted above. This was collected by a friend of mine who is doing some work on a very small limestone influenced stream on his property.

Eric this stream is about 75-80 miles SW of Clarks and the particular run this guy was harvested in typically goes dry in the summer (actually a runoff trib to the stream he is working on). I have an invite to come back and fish the larger branch this week so we may need to try and capture another for further photographic studies.

My gut reaction was that it was an iso based on how strongly it swam in the video my buddy took but then the distinct lack of the dorsal stripe and coloration differences caused me to doubt that hence my post here. Let me also add that my typical ID process goes something like Spences' Little yellow bug system so counting gill truncations or describing their shape is beyond me.
JW
"old habits are hard to kill once you have gray in your beard" -Old Red Barn
EntomanMay 13th, 2012, 4:17 pm
Site Editor
Northern CA & ID

Posts: 2604
John,

Based on your description of the habitat, I think Paul's suggestion of Siphlonurus (Gray Drake) is closer to the mark, especially if Eric agrees. I don't know much about metretopodid life history but I do know that siphlonurids love to migrate out of main stems to hatch; even flooded bogs or the merest trickles that dry up in the Summer.
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman
KonchuMay 13th, 2012, 4:59 pm
Site Editor
Indiana

Posts: 496
been watching to see how this would play out; i've been suspecting Siphlonurus, and the habitat is right
CrepuscularMay 13th, 2012, 5:34 pm
Boiling Springs, PA

Posts: 917
I think you guys pretty much covered it all without me! Now that I know the habitat,I'd call it Siphlonurus too. Pretty brave of me I know :)... The only place I know of in my area that has a fairly good population of Siphloplecton basale is Clarks creek, which is why I was trying to find out if it came from there. I thought it looked a little "stout" to be Siphloplecton but the angle was weird.
EntomanMay 13th, 2012, 6:42 pm
Site Editor
Northern CA & ID

Posts: 2604
Well there you go, John. Pretty good consensus built on Siphlonurus.
Sorry John (WIflyfisher)... I tried to keep you in the game, but no cigar. :)
"It's not that I find fishing so important, it's just that I find all other endeavors of Man equally unimportant... And not nearly as much fun!" Robert Traver, Anatomy of a Fisherman

Quick Reply

You have to be logged in to post on the forum. It's this easy:
Username:          Email:

Password:    Confirm Password:

I am at least 13 years old and agree to the rules.

Related Discussions

TitleRepliesLast Reply
Re: Callibaetis sp.
(2 more)

In the Identify This! Board by Millcreek
6Apr 30, 2015
by PaulRoberts
Re: A Strange One
In the Identify This! Board by Taxon
10Aug 27, 2006
by Flymedic
Re: Near French Creek, PA
In the Identify This! Board by Lyrae
5May 13, 2007
by GONZO
Re: Siphlonuridae
In the Identify This! Board by Willmilne
9May 25, 2009
by Taxon
Re: Need help identifying!!
In the Identify This! Board by Jsawatzky
5Jul 5, 2015
by Creno
Re: Great Speckled Olive or Gray Drake
In the Identify This! Board by MItroutbum
6Jun 20, 2008
by GONZO
Re: Stillwater Mayfly Nymph Collection Techniques
In the Insect Order Ephemeroptera by Taxon
9Aug 11, 2011
by Goose
Re: 2 Matflies in need of names
In the Identify This! Board by Jummbeau
6Apr 23, 2008
by Jummbeau
Re: Assorted Nymphs From The Russian River
(1 more)

In the Identify This! Board by Millcreek
6Jun 4, 2016
by Creno
Re: Paralep adoptiva vs. E. pluralis
In the Identify This! Board by Adirman
13May 16, 2013
by Adirman
Most Recent Posts
Re: Brand new member, fly fisherman, and boat coveter
In General Discussion by Stickstring (Wbranch replied)
Re: Puzzled on this mayfly, not even confident on family
In Male Heptageniidae Mayfly Spinner by Troutnut (Millcreek replied)
Re: Hesperoperla or Calineuria
In Male Calineuria californica Stonefly Adult by Millcreek
Quick evening trip to the South Fork Snoqualmie
In Site Updates by Troutnut
Re: Fishing with My Nephew: Sixth Annual Trip
In Fishing Reports by Martinlf (Partsman replied)
Re: Spinadis simplex
In Female Heptageniidae Mayfly Dun by Taxon (Troutnut replied)
Re: Neoleptophlebia
In Neoleptophlebia Mayfly Dun by Millcreek (Troutnut replied)
Neoleptophlebia
In Neoleptophlebia Mayfly Nymph by Millcreek
Neoleptoptphlebia
In Neoleptophlebia Mayfly Nymph by Millcreek
Neoleptophlebia
In Neoleptophlebia Mayfly Nymph by Millcreek