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

> > Insect photos on CatskillFlies website

This topic is about the Mayfly Genus Ephemerella

This genus contains the legendary Hendricksons and Sulphurs of the East and the equally important Pale Morning Duns of western waters.

No scientific name in American angling literature is more renowned and at the same time capable of more confusion than the genus name "Ephemerella." It is important that anglers have a good overall grasp of its taxonomic history if they are to make any sense out of the rich literary heritage involving this mayfly name.

By the time American angling literature began to take serious note of entomology in the decades of the early to mid 20th century, Ephemerella was considered a "super-genus" in the family Baetidae, containing all of the important species to anglers in the subfamily Ephemerellinae. Taxonomists organized them by association with "type" species that were referred to as "groups" within this very large and unruly genus.

This organizational structure held sway until the 70's when they were recognized as separate from the Baetidae with their own family, the Ephemerellidae. The "groups" (after a little name changing and reorganization) were given subgenus status, but in conformance with taxonomical convention,the nomenclature retained the use of the name Ephemerella when referring to individual species genus status. More change occurred towards the end of the century as consensus formed around the subgenera achieving full generic status. The broad use of Ephemerella was then dropped in favor of the new generic names.

These changes were necessary in that they addressed many problems exposed in older taxonomies. Unfortunately, all during this period the changes were reported with varying degrees of accuracy and acceptance. For anglers this was exacerbated by the continued use and reliance on older entomology texts in many circles. Be that as it may, recent or updated angler entomologies now recognize that many of the old Ephemerella species are spread out among several genera in the Ephemerellidae family. These include the various Blue-Winged Olives and Western Green Drakes of the Drunella genus as well as several important species scattered in genera like Attenella and Serratella, to name a few.

Despite these revisions in classification, the Ephemerella genus still contains arguably the most important species in North America, and remains a "super-genus" to anglers.

There is a lot of variation; refer to the genus species hatch pages for details. Read more...

There are 155 more specimens...

The Discussion

JpsullyMay 23rd, 2008, 5:22 am
bedminster, nj

Posts: 4
Hey Jason:

There are some beautiful photos posted on that forum under the "Fishing" section, and titled "Bugs are cool". My guesses as to ID are: first 2 pics (same fly)- Stenacron (orange tint, two tails, mottled wing and banded femur), third pic - Ephemerella Attenella (3 tails, slate wings and faded olive body), last 2 pics (same fly) would appear to be Maccafertium (Grey Fox - not March Brown) based on 2 tails and light coloration. Am I correct in my assumptions? Any help you could provide would be appreciated. Thanks.

GONZOMay 23rd, 2008, 6:17 am
Site Editor
"Bear Swamp," PA

Posts: 1681

Just in case you'd like another (unsolicited) opinion while you're waiting for Jason's response, I'd say you've got it about right. Here's what I see:

1st mayfly (female dun)--probably Stenacron interpunctatum. It's a bit hard to see the telltale Stenacron wing marking in the photo, but it sure looks like it.

2nd mayfly (female dun)--could be Attenella attenuata (or Drunella lata). You may see the former in older texts as Ephemerella attenuata and the latter as either Ephemerella cornuta or Drunella cornuta. (Both of these could be hatching now. Size might help. If it's ~ 10mm, it's probably lata--later season hatches of lata are smaller. If it's ~ 8mm, it's probably attenuata.)

3rd mayfly (male dun)--Maccaffertium vicarium. This used to be split into March Brown (Stenonema vicarium in older texts) and Grey Fox (Stenonema fuscum in older texts), but both are now under M. vicarium.

I hope that helps.
JpsullyMay 23rd, 2008, 7:29 am
bedminster, nj

Posts: 4

Thanks, that is definitely helpful. You are right on with your details.
Just what I was looking for.

GONZOMay 23rd, 2008, 7:31 am
Site Editor
"Bear Swamp," PA

Posts: 1681
My pleasure, JP.
SofthackleMay 24th, 2008, 5:45 am
Site Editor
Wellsville, NY

Posts: 540
Nothing to do with your flies, JP, but where in blazes have you been?

"I have the highest respect for the skilled wet-fly fisherman, as he has mastered an art of very great difficulty." Edward R. Hewitt

Flymphs, Soft-hackles and Spiders:

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: 2 tails or 3
In the Mayfly Species Maccaffertium vicarium by Snagy
1Feb 6, 2010
by Taxon
Re: I'm pretty unsure about these IDs
In Female Ephemerella excrucians Mayfly Spinner by Troutnut
5Dec 18, 2013
by Brookyman
Re: New Mexico ???
In Beginner Help by Hankaye
3Apr 19, 2013
by Sayfu
Re: Recent evenings at the Drake Hotel
In General Discussion by Crepuscular
45Oct 8, 2014
by TroutBums
Re: cahills
In the Mayfly Genus Stenacron by LittleJ
8Dec 1, 2006
by Troutnut
Re: Here's two I could use some help with from East Tennessee!
(1 more)

In the Identify This! Board by BrettHRomer
6May 8, 2008
Re: learning to tie
In Fly Tying by IEatimago
12Jun 29, 2007
by IEatimago
Umbrella hook Western March Brown Dun pattern
In Fly Tying by Rgiffin
Re: Baetis v Empheralla Attenuata
In the Identify This! Board by Byhaugh
5Dec 18, 2013
by Entoman
Re: Unidentified Baetidae
(2 more)

In the Identify This! Board by Benthosfan
8May 5, 2021
by Benthosfan
Most Recent Posts
Re: Are mayflies declining?
In General Discussion by Wiflyfisher (Adirman replied)