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I'll try to open up the angling perspective a bit. It became apparent to me that there is quite a bit of variability within species, that can make it difficult for anglers especially to separate them out. If they are indeed different species then there are likely behaviors we can capitalize on. But we first have to know who is who. And I guess we look to the entomologists to sort that out.

Here’s my fuzzy and outdated understanding of some of these mayflies in fishing terms, speaking from the archives of my experience. Maybe you guys can set me straight and offer some useful advice to anglers onstream.

”M. vicarium/fuscum”
I, like everyone else, thought they were separate but began to find what appeared to be both--the light and dark versions--emerging together. One day on one tiny creek I captured both “MB”s and “GF”s (or dark and light) together and it wasn’t due to post-emergence darkening. Some were dark mottled brown and others were pale greenish yellow with lighter mottling. These weren’t ithaca which were much paler and emerged later.

They never emerged dense in the small to medium sized streams I fished. But the large, vulnerable, and active, duns were noticed by the trout. A tactic I used was to fish a large hackled Haystack in MB colors (the more frequent coloration of the naturals), twitching it on the surface of larger pools to target the larger bug eaters. Strikes could be like eruptions! Very fun.

“subvaria”
The more I looked and saw, the more variation I began to find in subvaria too. Subvaria had a dark and light version that emerged together although it seemed in some places or times one was more predominate that the other. I called them “dusky plum” and “dusky tan” and either sex could be either color. I saw this on a number of different area waters.


Here’s a really dark specimen. It’s subvaria that was almost a dark slate color, esp the wings. The light version had a tan/khaki abdomen. All subvaria looked “dusky” or “sooty”.

They were an easy emergence to fish, from the pre-emergence nymphing (I used a nearly black “turkey ‘bou tailed nymph in head riffs –just killer), Comparaduns for the easily-accessible-to-the-trout duns, to poly-wings for the often concentrated spinner falls. The only thing that might cause trouble was high or cold water when the bugs would hatch but the trout weren’t paying attention. I always wondered if the dark version was a coloration that did better during cold snaps; Mebbe a relic form from the last ice agea (?). Can't think of an advantage to the lighter version; Mebbe it's just the predominant form? I know, really reaching here. But in the real world there tend to be reasons for much of this stuff.

”invaria”
I never did separate invaria and rotunda well, but have images I have labeled either and don’t remember why. In fishing, I ended up just calling them “invaria”. They emerged a good month later than subvaria. I saw quite a lot of variability in coloration of both bodies and wings in “invaria”. Some were pale translucent cream with light gray wings, with or without some gray/olive in the thorax, others were like a the tan subvaria but without the sootiness, and others were almost butter yellow with wings either med gray, or washed with yellow. Some females often had white eyes. I noticed that Spence’s likely "invaria” has dark eyes. http://www.troutnut.com/topic/3213/More-Bugs
The “invaria”s I knew were all about a size 14 (ranging from Mustad to Tiemco lol), where the subvaria’s were all solid Tiemcos).

I knew (or recognized) invaria on the small to mid-sized streams I frequented as usually emerging from faster riffles mid-morning into very early afternoon. The invaria emergences rarely produced that much fishing for me bc it seemed they emerged sporatically, and from water faster than most trout fed in. And they also seemed to leave the water faster than those wonderful subvaria’s. (No they weren’t Heptageniids). Little 'bows took whacks at them from pockets in the riffs, but the duns were airborne by the time they reached the better trout holding just below.


This one I had labeled “rotunda?” and it had emerged from my stream tank. Notice the light eyes. It represents the pale translucent/pale gray-winged version vs the yellow ones –like in Spence’s image a short time ago. I apologize for the image quality as they were transparencies I re-shot with a digital camera. Colors are off bc the orig was shot under plant lights in a stream tank and then digitized under blue sky. I chose the shot though bc it shows physical features fairly well.

”dorothea”
dorothea began emerging at the end of “invaria”. Where subvaria was a “spring” emergence, and invaria a “late spring” emergence, dorothea was decidedly a “summer” emergence. Dorothea was smaller than invaria (~#18) and less variable in color -truly a little "sulphur". Their emergences were heavy in some streams I frequented. In general, the nymphs could be found in a variety of current speeds but more so in slower currents than either subvaria or invaria. They didn’t seem to mind silty substrate, whereas the “invaria” I knew were found in riffles. They (dorothea) could be a frustrating emergence to fish, with the water frothing with feeding trout (looked like handfuls of stones being pelted onto the water at times) often just below head riffs of good pools. You could see the action at its peak from a distance! Trying to catch fish in that melee was maddening. Dry’s often failed and I assumed they were picking through large numbers of emerging nymphs. (This was different on the big Delaware where dorothea emergences could be great with huge numbers of emergers/duns. Low riding drys, and emerger patterns, duped lots of fish.)

As the season progressed and got hotter, the emergences came at dusk (maybe a.m. too but I don’t remember) and these could be intense. And the spinnerfalls came …after dark :( . I have photos of glorious clouds of spinners over the riffles in pitch black –their wings in the camera flash looking like a billion stars. I could catch fish then by unceremoniously dragging a spinner, or any other wad of wet dubbing on a hook, across the surface. But that was more like bass-bugging than neatly and precisely covering rises.

I cannot say much about infrequens and inermis as I just haven’t had that much time to spend with them here in Colorado. I know infrequens is now considered a subspecies of dorothea, and inermis is now lumped into (synonomous with) excrucians. Yes?

“Ephemerella X”
I came upon an emergence of very subvaria-esque Ephemerella’s in late May on Owasco Inlet in central NY. A #16 that was too late for subvaria by a month, timed with invaria. The dark root beer brown spinners fell during daylight and were memorable –dense enough to bring up some of the better bug-eaters on this stream. It was like fishing a subvaria spinner fall.

An emergence described by Bob Caucci back then fit, and it was (then) a mystery to him and he dubbed it “Ephemerella X”. Possibly this is Ephemerella aurivillii? Here’s an image:


Does anyone recognize this eastern late-May emerging dun??

This thread has made me reflect on the need to step back so as to notice the "forest for the trees."

The "Information Age" has changed everything... In the prior age, flyfishing was very esoteric (ask the guys that started before the mid 70's how they learned to tie flies or cast). A few enlightened souls with connections in academia and/or reputions as sports writers collected specimens of the important fishable hatches of the day and after having them identified by accredited biologists, revealed their "names" and related behaviors to a ready audience. Trusted "reviewers" from the fraternity hailed these various works as ushering in a new era of commonality and stability that would forever banish confusion and codify fishing techniques. They were laying the cornerstones of an edifice that would stand immutable. The famous authors did little to dispell this notion, even though the fallacy of this proposition was already in evidence from the beginning. Remember Iron fraudator? This illusion was allowed to ferment largely unchallenged only due to the relative slowness of communication and lack of access to information. Even the work of science was moved forward at a snail's pace by comparison to today.

Now fast forward... Science has tools and communication capabilities allowing them to get results in months that formerly took decades, not to mention exploring areas of relationship unthought of just a few years ago. The same with flyfishing. Instruction video's, guides, casting instructors, and incredible equipment improvements now allow the fervant angler to acquire skills so quickly, it is often breathtaking to many oldtimers. "Experts" are springing up all over the place.

Add to all this the fact that nature has not stood still. The dirty little secret is fishable hatches and fisheries wax and wane over time. The idea of "Garden of Eden" stability is a chimmarra. With what we've done to our watersheds (especialy deforestation), it's a testament to nature's resilience that our natural world has even a dim resemblence to the past in terms of its fauna. Ironically, those with perhaps the most passionate desire to "preserve" what we have left now possibly pose the greatest threat by being the transport vehicles for pathogens and introduced species of profound consequence.

Where does this leave us? First off we need to recognize that there is no dichotomy between science and it's application with the rod or at the vise. Does that mean that us oldtimers won't continue to grouse when names are fussed with? No... because it's too much fun. It isn't serious though. Science must do what it must do in the quest for knowledge and serious anglers are well aware of this. Besides, the "confusion" is perhaps the last bastion in our sport that allows a little of the old esoteric spirit to flourish.:)

Secondly, we live in a day when anybody can take a photo of a critter on a window sill or leaf and post it online to gather opinions about "what it is". This has created a bit of a delemma. While scratching heads over these may be fun for some, usually the submittals causing the most scratching envariably have no relation to practical fishing. There are thousands and thousands of aquatic insect species, most with several stages and many permutations. It is undeniable that the vast majority will have no impact on anybody's angling. This is important to keep in mind if for no other reason than to maintain our angling sanity.:) As I said earlier in this post, the oldtimers identified and focused on "the fishable hatches" of their day if for no other reason than it was impractical to do otherwise. I suggest we as modern anglers should probably maintain focus on our "fishable hatches". Goes along with the old saying, "Just because we can do something doesn't mean we should". Having said that, there is nothing wrong with being both "bird watcher" and angler. They are two different hobbies though, and this reality often gets confusing for some. Especially when the lines get blurred at times on this forum.

Regards,

Kurt

Hi Paul,

Sorry for blowing by your post without comment. I was writing the one above at various times during the morning and didn't see yours until after posting mine.



Way too big for either the similar colored E. excrucians or S. serrata. Too early as well, I think. Why can't it be E. subvaria?

Regardless, you are asking the same questions I am. I can't think of any ephemerellid with greater variety in appearance than excrucians. In terms of similarity, none closer than a lot of specimens of invaria and dorothea infrequens I've seen. We've been discussing duns though. I think the answer lies with the nymphs. This issue is even bigger with the baetids where specific and highly differentiated types of hind wing configuration no longer seem to matter as much.

Regards,

Kurt

Kurt,
I'm more inclined to "lump it" into invaria, by timing, pale legs, and esp, the pale yellowish wings. But ... that would just add another color scheme to invaria, although it's true I haven't separated rotunda.

Rick Hafele made these comments about PMD's coloration:

"There’s been a bit of debate about just what species lives in western streams and taxonomists recently changed the species name from Ephemerella inermis to Ephemerella excrucians. This means nothing to the trout, or the flies you use to match them, so you can now forget it ever happened!"

and

"Well, if there’s one thing I’ve found from collecting aquatic insects for over forty years is that color is not a definite thing, even between individuals of the same species from the same stream, and PMDs seem to exhibit this color variability more than most."

He goes on to show photos of yellow and rusty "PMD" duns -doesn't say which species.

I wonder, can I get a home DNA kit? Is there one that would give instant results, with an onboard computer that would offer best fit down to subspeices level? And while I'm at it, it needs to fit in my fly vest. Am I getting spoiled? Sure would save us a lot time and confusion and let us get right down to biznez, eh!

Someday Paul, someday... Though it won't be a kit; it will be like Spock's tricorder, only the size of an Iphone. You'll just have to scan the bug for an instant read-out. Of course, you'll have to download the weekly updates to keep up with the latest taxonomy. Though it's true the fish will not care, I'll still be in line to get one. It will be nice to know the precise name of the critter my fraud is failing to imitate effectively:)

Kurt

Fellas...I think what the man is hinting at is...just relax and knot one on and get fishing! :)

Spence

Your Ephemerella X looks an awful lot like this guy, who I formerly had placed in a couple different species but have put with Ephemerella needhami now after Gonzo made a convincing case for it. I'm guessing the X is needhami, at least for the specimen you pictured. The one I photographed on the Delaware was a small 16 or large 18, but that's within the range of variation for a single species at different places/times.

So...that's what the barcoding is all about! :)




The reason I want to know the identity is to be able to get under the skin of the activity. I want to know the ecological parameters and behaviors ahead of time. The most satisfying fishing for me has occurred bc I was hip to some activity. Being there when it happens and knowing what to do is really neat. Not that it always pans out as expected.

As to tying... sure one fly may pass for another, sometimes not. If one didn't know that dorothea specifically has a habit of emerging subsurface, it could make for frustrating fishing with a traditional hackled dry. Think of the caddisflies –what confusion they caused until their varying behaviors were fathomed. At least we can know better what behaviors we are trying to imitate. Turns the focus of our fly patterns fro what flies look like in hand to what they look like in the water. I dare to venture that fly-tying is still in its infancy, and ID is first.

Jason, that sure looks like it. But... I thought needhami were very dark, with blackish wings -similar to S. deficiens. That's as I remember it. Could well be wrong.

I want to jump off of Rick Hafele’s comment about coloration. He said:

" Well, if there’s one thing I’ve found from collecting aquatic insects for over forty years is that color is not a definite thing, even between individuals of the same species from the same stream, and PMDs seem to exhibit this color variability more than most. The photos of nymphs and duns shown here, where collected from the same stream, and even the same rock, yet you can see significant color differences. I have seen similar color differences for many other species. This shouldn’t be that surprising, since what other animals of the same species all come in the same color? Color variation between individuals is the norm not the exception, and that is true for insects as well."

I have to disagree that:
“This shouldn’t be that surprising, since what other animals of the same species all come in the same color? Color variation between individuals is the norm not the exception, and that is true for insects as well.”

Most creatures are pretty darn close in appearance. Selective pressures, predation being a strong one, keep them within a pretty narrow range. I can give examples but will spare myself the typing (think the two dominant genes for coat color in whitetail deer, blue lobster, why falconers say their birds crack the polarized flock problem by picking out the odd bird, …). Think houseflies, bumblebees, moths, butterflies ... I'd argue MOST creatures including insects are pretty narrow in coloration.

It appears that (at least some) mayflies are the exceptions. Why the two colorations in vicarium, subvaria, and the variability in "PMDs"? My best guesses are that predation pressure is NOT as directly tied to color as we FF might guess. And that something else is way more important. The dimorphism seen in the first two may have to do with temperature sensitivity, as the generalized pattern of mayfly coloration seasonally has been recognized as being dark in colder months and pale in warmer months -so there is likely selective pressure there. This might indicate pressure on growth rate, activity (flight -maybe predation by birds is the greatest threat to adults, a speedy getaway favoring the dun. The nymphal shuck that camos the insect from fish for the majority of its life is simply shed.), and/or the issue of desiccation for summer emerging species, esp important for the survival and effectiveness of the imagos.

Or conversely, maybe fish predation IS an important factor at the often vulnerable "dun" stage, and dimorphism is a response to selective feeding in fish? So...from the most and least vulnerable duns, which species show variability?

I'm personally not looking forward to this. Instead of my completely torn and tatered copy of Borger's little color chart I have carried around for so long I forget it's still there in my inside vest pocket, I'll have little tabs (like those hanging from my key chain for "Speedy Reward Points") with bar codes on it for all the known aquatic bugs of my home water...Based on the virtual "Hatch Chart" all I'll need to do is swipe it along my GPS/PDA and it will tell me exactly which fly to use...It will know this because I've already scanned all the flies I've tied and are now in my vest in to its data base...Maybe we could get the actual bugs to wear a barcode or data chip just above their ass end so I can scan them and know what to tie next time...

I used to joke that it would be nice sometimes if the fish would hold up little color coded flags so I'd know what they were dining on, but I was just kidding! "Hey there mister angler, dumm Kopf! Don't you see those sulphur spinners on the water?! Forget those hatching stones...We no longer can even see them." Spencer will never forget, be able to live down, "Spencer's Hole of Shame!", May 1991...Ouch! I still can't walk by it and not feel the pain! ;) Years later I finally had a triumphant night there in front of a small crowd but "the first cut is the deepest."

If any of this comes to pass I'll have to re-think it all and grab a 12-pack, some worms, and a couple bobbers and head on down to the old creek near my grandmothers farm like I did as a kid...Piece of grass hanging from my mouth and all. Maybe I'll even get a nap in.

I don't own a GPS because nothing but good has ever come from me getting lost in the woods.

Spence

Wonderful quote, Spence. I hear you. We have one here in the mountains: "Use the quads God gave you."

What I find disturbing about the technological bent is the painful process of getting there -like learning anew some software upgrade. And it seems to get tougher the older I get. But once we have it, know what to do with it, and its limitations, then it just becomes another tool. I wouldn't trade my knowledge for that can of worms. And probably neither would you. Nice place to visit, every once in a while.

Now if we could only get rid of the @#%#$%!! batteries.

Jason & Paul -



Yes, invaria is an option due to size and wing color, not to mention time of emergence and tail articulations. But the body color is more suggestive of subvaria. While the contrast between the light legs and dark body might suggest needhami or excrucians, your specimens size as well as the tail articulations preclude excrucians and look a little too pronounced for needhami as well. There are strains of subvaria males that are reported to have lighter wings and "ephemerellid style" lighter areas basaly on the leading edge of their forewings, and Hendricksons have been reported to trickle off this late. Though the body color is a better match with subvaria then with invaria, I have to admit the contrasting paler legs (though not nearly as dramatic as with the other species mentioned and still look grayish tan) are a little problematic. I can certainly see the cause for confusion.



I agree the body and eye color are very similar to Paul's specimen. Beside the obvious difference in size, there are other areas of divergence though. The forewing shape is different, the legs are much lighter causing greater contrast with the body, and the tails are especially troubling because they lack the very distinct articulations found on Paul's example and needhami too for that matter (at least basaly).

Though your photo could very well be needhami, it looks like it could also be an eastern excrucians. Do you remember Gonzo's rationale? I looked for it on the hatch page but only found from my quick scan a conversation about another family. Gonzo didn't participate as far as I could tell.

Serratella serrata is another similarly colored critter and is on the tiny side as well, but it also has distinct tail articulations.

regards,

Kurt

Someone was telling me the other day about a study where they seem to have found that these gadgets are causing some to lose their natural sense of direction...It seems you have to use it or lose it.

I was in Berlin in 2006 for a friends wedding. My friends father was driving my wife and I to Potsdam for the church and reception after. He had just bought a new GPS unit and was proud of it to all get out. Somewhere between Berlin and Potsdam (Like Detroit to Ann Arbor) he began to doubt the device...He pulled over, beginning to sweat a bit and afraid we would be late and started to chat with his wife in the back seat...I kind-of understood what was up and I pointed out the window and said, "Potsdam is that way." He was so rattled he didn't believe me either and was probably wondering how a guy from Detroit had the nerve to tell him which way to go...I said, "There see...The road sign up there says Potsdam straight ahead." ;) Es war wunderbar!

Spence

PS I started to post yesterday that I thought your bug was needhami and pulled the post after a half hour or so...I had sent an email up to Gates' about a so-called "Dark Henrickson they had listed on their Hatch Chart...They wrote me back it was the web masters typo...I started to doubt myself and yanked the post. I was having doubts due to its size...

Well...heck, I'm going to have to dig up my records and journal and see if something useful is missing from my description.

Exactly! Jokes about my flies not working and downloaded updates aside, thats why I'd be in line for the gizmo. Nice job with words, Paul...

Well... this reminds me of the time I tried to ask an archeologist about a bone I'd found. He just seemed exasperated by the questions and finally set me straight saying that without the site--the particulars about the deposit--the fossil is all but useless.

I checked my journals and did not find the record of its capture. All I can say is what is coded on the slide frame. This dun emerged from my stream tank on May 22, 1997. The unidentified nymph was collected from Mill Creek, a tiny trib of Fall Creek near Ithaca, not from Owasco Inlet as previously stated. I thought I might find that it was indeed needhami, as I'd collected some needhami nymphs (or aurivillii) and might have had them in my tank. No such luck. Dunno who that dun was. Mill Creek btw does not contain vegetation, but is a small farm/cattle degraded trib with much silted cobble. It has some springs I never located (on private property above my collection near the Fall Creek confluence) evidenced by brook trout found at the collection site.

The spinner falls on Owasco Inlet I mentioned in the original post were a #16 (not #14) "dark root beer brown" Ephemerella spinner who's ID I wasn't sure of. What bothered me was the generally smaller size (I knew invaria as a #14) and, especially, it had a shorter abdomen. I saw those early eastern Ephemerella (subvaria and invaria) as having long abdomens. This one had a shorter abd and a proportionally thicker thorax -more compact looking. My nymph sampling during that period (Mid-May) turned up what I described in my journal as "invaria ready to pop with dark wing pads, dorothea's immature yet".

I see in some of Jason's pics, some "invaria" with what appear to be short abdomens, both a male and a female:
http://www.troutnut.com/specimen/182
http://www.troutnut.com/specimen/179
(Interestingly, these two were collected on May 23, and 22, the same date as my so-called “Eph X” -although from an entirely different state.)

Likely, invaria is a morphologically highly variable species. Caucci's "Ephemerella X" may simply demonstrate the confusion this engenders. With several simlilarly-built species (subvaria, invaria, rotunda, dorothea, excruciens, needhami) and variability within, I guess what’s really is needed is one of those vest-pocket DNA tricorders. Sure would be nice to sort them out once and for all. Then again we may just find that “invaria” esp is a variable (even plastic?) “species”. We nerdy types might just be left wandering the wilderness with Spence (albeit generally happy).

One last observation: On the streams I fished around Ithaca, subvaria and invaria appeared to overlap a week or so with my journals recording my seeing "a #14 sulphur (likely invaria)" while I was fishing the last of the subvaria spinner falls during the first week in May. By the second week in May it was all X/invaria. Has there ever been any evidence of subvaria/invaria hybridization?

Paul. Someone once said, "ignorance is bliss" and our wanderings would be even more blissful if we could find where in the woods Spence left the "fishing-wagon" and that cooler filled with ice cold Molson's! :) :) :)

If there has...She isn't saying...;)

Boys...Maybe we are trying to jam a puzzle piece we found lying on the floor in to the wrong puzzle...Or, like you said Paul, maybe we just don't have enough solid information to pin this one down.

I have fished the same week for over 20 years on the Au Sable...That's in a row except for 2005 when my back said, "sorry fella, not this time!". The week is the week ending in Memorial Day weekend and it moves since the holiday is the last Monday of the month. During the years when I'm up earlier by nearly a week I've had the tail end of subvaria and the beginning of invaria...If memory serves me well...it usually seems to be the last of subvaria as spinners...But I wouldn't doubt that there may be some stragglers. For what this is worth.

Spence

Someday long after we're gone we'll likely end up meeting on a cloud right at that very spot. But I'll most probably wind up saying, "Spence, should I ask the BIG GUY about Ephemerella invaria?"

For most of us here on this site, it wouldn't be heaven otherwise! :)

What will really happen when you and I find ourselves at St Peter's gate? We will be greated by Roger and he'll say, "Boys! Here's your updated taxonomy charts...This one is for you Paul and it takes care of "Hatches" for ya, and this one's for Spence and it brings Leonard's Michigan book up to date...Now this may not be the final version since some of the "bug boys" are, as we speak, in committee with the Big Guy...Turns out that Gonzo & Kurt still! aren't completely happy with a few things and the Big Guy has to check his stream log for some of the details...;) There's a rumor going around that Creno, Konchu, and Jeff were sent to the penalty box for a bit...Turns out the Big Guy wasn't too happy with this DNA stuff...Cut a little to close to the puzzle, I guess...And it turns out Spence seems to have an in with the Big Guy or otherwise he wouldn't be standing here right now...Seems the Big Guy wants to re-instate Spence's little buddies Pseudocloeon anoka and B vagans...Who knew?!"

Spence

Spence - Thanks for putting things back in perspective. Good humor has a way of doing that. Perhaps Id's do get kicked about a bit too much, but it is fun.:) Even though they seem to be filled with the excesive clutter of speculation at times, when it's all said and done I think we end up knowing more than when we start these threads. At least I do anyway. Notice that the tougher ones tend to get pretty long?

Paul - Having said the above, It is a sign it's probably time to wrap it up when the topic gets so long that relevant quotes can't be easily found for inclusion in a follow-up post.;) Especially when the topic gets bifurcated into separate threads:) After rereading your fieldnote excerpts, I'm inclined to agree with you that it's probably a dark color phase of invaria. As Lloyd pointed out, many anglers assume they are always sulfurish, and I was one with that prejudice. It's been shown here on Troutnut they can be darker and/or have olivacious tones as well. Remember Spence's green one (the way it looked to me)? That had me thinking cornuta until you pointed out the forelegs. Luke and his associates have combined enough species into excrucians that it can be yellow, green, or brown, so why not invaria? BTW - I don't think hybridization is a likely reason for the dark subvaria "look" of the X dun.

Also, there are several things that both you and Lloyd said regarding ephemerillid wing shape that make the subject worthy of its own topic. I've been doing a lot of eyeballing at them the last day or so after your guy's comments. I think I'm noticing something very interesting, but want to verify with a little more research first.

Regards,

Kurt