Header image
Pteronarcys californica

The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.

Male Eurylophella (Chocolate Duns) Mayfly Spinner Pictures

This mayfly was collected from the Teal River in Wisconsin on June 4th, 2005 and added to Troutnut.com by Troutnut on May 24th, 2006.

Discussions of this Spinner

5 replies
Posted by Taxon on Jul 10, 2006
Last reply on Mar 7, 2013 by Entoman

Your identification appears spot on. You may well have already considered them, but here are three key matches:

1} Genitalia illustrated in Leonard & Leonard p. 125 figure 75, which seems to match the claspers perfectly, and would likely match the penes perfectly as well, were they not a bit damaged
2) Sternites "with four small dots sometimes elongaged into narrow streaks" as described in Leonard & Leonard p. 50
3) "stigmatic area of fore wing milky" as described in Leonard & Leonard p. 50
Thoughts on this identification?
Posted by Troutnut on Jul 10, 2006
Last reply on Jul 10, 2006 by Troutnut
I've got several specimens of this small Ephemerellid species, and my best guess is Ephemerella needhami, but I'm still unsure. There are species of Eurylophella with similar stripes whose nymphs were common at the same time and in the same general location, but I didn't do really comprehensive nymph collection.

Start a Discussion of this Spinner:

You must log in at the top of the page to post. If you haven't registered yet, it's this easy:

Troutnut.com is copyright © 2004-2023 (email Jason). privacy policy