Mayfly Genus Ephemerella (Hendricksons, Sulphurs, PMDs)
Taxonomic Navigation -?-
Kingdom Animalia (Animals)
» Phylum Arthropoda (Arthropods)
» Class Insecta (Insects)
» Order Ephemeroptera (Mayflies)
» Family Ephemerellidae (Hendricksons, Sulphurs, PMDs, BWOs)
» Genus Ephemerella (Hendricksons, Sulphurs, PMDs)
11 species aren't included.
Common Name
| Match | Common Name |
 | Hendricksons, Sulphurs, PMDs |
There is a lot of variation between the species; read about each one for the details.
Where & When
Ephemerella nymphs inhabit all types of water. This genus is most important in the East and Midwest, where the major species hatch in the spring and a few continue into the summer. In the West, the other closely related genus Drunella takes on greater importance, but the Pale Morning Duns of Ephemerella are still important in the summer.Spinner Behavior
The concentrated evening spinner falls of many species in this genus are some of the best fly fishing events of the spring.They are also one of the groups of mayflies most prone to the unfortunate behavior of mating and ovipositing over blacktop roads hundreds of yards from the river.
122 Mayfly Specimens in the Genus Ephemerella:
Ephemerella invaria (Sulphur) Mayfly Spinner
View 12 Pictures
View 12 PicturesRegion: Upper Midwest
Collected Jun 3, 2005
Added May 25, 2006
Ephemerella needhami (Little Dark Hendrickson) Mayfly Spinner
View 12 Pictures
View 12 PicturesRegion: Upper Midwest
Collected Jun 4, 2005
Added May 25, 2006
Ephemerella septentrionalis Mayfly Dun
View 10 PicturesI'm pretty sure this dun belongs to septentrionalis, because her legs are just too long for invaria. I know that species is in this system because I collected several nymphs some miles downstream.
This really pretty mayfly was in kind of bad shape when I found it crippled on the surface, and bouncing around in my container with a bunch of green drakes didn't help.
View 10 PicturesI'm pretty sure this dun belongs to septentrionalis, because her legs are just too long for invaria. I know that species is in this system because I collected several nymphs some miles downstream.This really pretty mayfly was in kind of bad shape when I found it crippled on the surface, and bouncing around in my container with a bunch of green drakes didn't help.
Region: Catskills
Collected Jun 1, 2007
Added Jun 4, 2007
6 Streamside Pictures of Ephemerella Mayflies:
View Full Size
Here's an above-the-water view of a stillborn (Stillborn: In fly fishing, a stillborn insect is one which got stuck in its nymphal or pupal shuck during emergence and floats helplessly on the surface instead of flying away. It is a specific class of cripple, although it is sometimes used interchangeably with that term.) Ephemerella subvaria dun which I also photographed from below the water.
In this picture: Mayfly Species Ephemerella subvaria (Hendrickson).
View Full Size
In this picture: Mayfly Species Ephemerella subvaria (Hendrickson).
This Ephemerella invaria sulphur dun got stuck in its shuck (
Shuck: The shed exoskeleton left over when an insect molts into its next stage or instar. Most often it describes the last nymphal or pupal skin exited during emergence into a winged adult.) trying to emerge. This isn't exactly a "natural" pose for a photograph, but it kind of shows what an emerger pattern could look like.
In this picture: Mayfly Species Ephemerella invaria (Sulphur).
Here's an underwater view of the pupal shucks of several already-emerged Brachycentrus numerosus caddisflies.
In this picture: Mayfly Species Ephemerella invaria (Sulphur).
37 Underwater Pictures of Ephemerella Mayflies:
This Ephemerella subvaria (Hendrickson) nymph picture is one of my favorites.
In this picture: Mayfly Species Ephemerella subvaria (Hendrickson).
In this picture: Mayfly Species Ephemerella subvaria (Hendrickson).
There's a large Ephemerella subvaria nymph in the top left.
In this picture: Insect Order Trichoptera (Caddisflies), Mayfly Species Ephemerella invaria (Sulphur), and Mayfly Species Ephemerella subvaria (Hendrickson).
In this picture: Insect Order Trichoptera (Caddisflies), Mayfly Species Ephemerella invaria (Sulphur), and Mayfly Species Ephemerella subvaria (Hendrickson).
Recent Discussions of Ephemerella
Aw Shucks 7 Replies »
Posted by Martinlf on May 19, 2009 in the species Ephemerella invaria
Last reply on May 21, 2009 by Wiflyfisher
OK, this is going to seem like a major duh experience for some of you, but the other night I found a sulphur spinner on the door of a bathhouse in a campground I was staying at. Looking for other bugs I then saw a pale nymph shuck on the door. I was totally confused. A nymph this far from the stream? Was this some alien bug? Looking closer I noticed that the shape was too slender for a nymph and that the wing pads were more like little protruding pockets--and it hit me. Spinner shuck. I knew that mayflies molted to produce a spinner, but I had thought the shuck would be more insubstantial--something that would be flimsy and lack form. This was so cool, and at the same time I felt so silly for thinking it could somehow have been a nymph shuck. It's the first spinner shuck I've seen, but I assume that I'll start seeing them everywhere now, like a new word you learn. Anybody else have a spinner shuck story?
Replypmd hatches in ny? 3 Replies »Posted by Trouthunter on Apr 18, 2009
Last reply on Apr 19, 2009 by GONZO
I was recently told by a close friend of mine that in the southertier of ny ( finger lakes region) that we have very good hatches of pmds. I was hoping that someone could confirm this or otherwise before I tye up patterns. I have seen what I believe are sulphurs with slightly the same body and wing coloration but again thought that these couldn't be the famed insect.
Replypmd hatches in ny?Posted by Trouthunter on Apr 18, 2009
I was recently told by a close friend of mine that in the southertier of ny ( finger lakes region) that we have very good hatches of pmds. I was hoping that someone could confirm this or otherwise before I tye up patterns. I have seen what I believe are sulphurs with slightly the same body and wing coloration but again thought that these couldn't be the famed insect.
ReplyHatching HendricksonPosted by Martinlf on Oct 14, 2008 in the species Ephemerella subvaria
Here's another hatching mayfly, this one stillborn. Click on "31 more specimens" and scroll down.
ReplyHatching SulphurPosted by Martinlf on Oct 14, 2008 in the species Ephemerella invaria
Click on "40 more specimens" and scroll down for one photo.
ReplyThere are 7 more topics.
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