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

Light Hendricksons

Scientific Name
MatchScientific Name
***Ephemerella invaria

This common name refers to only one species.

Mayfly Species Ephemerella invaria

These are often called Light Hendricksons.
This species, the primary "Sulphur" hatch, stirs many feelings in the angler. There is nostalgia for days when everything clicked and large, selective trout were brought to hand. There is the bewildering memory of towering clouds of spinners which promise great fishing and then vanish back into the aspens as night falls. There is frustration from the maddening selectivity with which trout approach the emerging duns--a vexing challenge that, for some of us, is the source of our excitement when Sulphur time rolls around.

Ephemerella invaria is one of the two species frequently known as Sulphurs (the other is Ephemerella dorothea). There used to be a third, Ephemerella rotunda, but entomologists recently discovered that invaria and rotunda are a single species with an incredible range of individual variation. This variation and the similarity to the also variable dorothea make telling them apart exceptionally tricky.

As the combination of two already prolific species, this has become the most abundant of all mayfly species in Eastern and Midwestern trout streams.
Ephemerella invaria (Sulphur Dun) Mayfly NymphEphemerella invaria (Sulphur Dun) Mayfly Nymph View 8 PicturesThis small Ephemerella invaria nymph was at least a month away from emergence.
Collected April 19, 2006 from in
Added to Troutnut.com by on April 21, 2006
Male Ephemerella invaria (Sulphur Dun) Mayfly DunMale Ephemerella invaria (Sulphur Dun) Mayfly Dun View 7 Pictures
Collected May 26, 2007 from in
Added to Troutnut.com by on June 4, 2007
Male Ephemerella invaria (Sulphur Dun) Mayfly SpinnerMale Ephemerella invaria (Sulphur Dun) Mayfly Spinner View 12 Pictures
Collected June 3, 2005 from in
Added to Troutnut.com by on May 24, 2006
Top 10 Fly Hatches
Top Gift Shop Designs
Top Insect Specimens
Miscellaneous Sites