Troutnut Forum > Fly Hatch Talk > Anyone know more about Ephemerella septentrionalis?
This topic is about the Mayfly Species Ephemerella septentrionalis
The only reference I've found to this species is in Fly-Fishing Pressured Water, which states that Ephemerella septentrionalis sometimes supports hatches of Ephemerella invaria, and calls it invaria's "sister sulphur." Read more...
There are 1 more specimens...
The Discussion
| Troutnut | May 18th, 2007, 9:37 pm | |
| Fairbanks, AK Posts: 1113 | I found about one sentence on these in Gonzo's book, and haven't seen them mentioned anywhere else in fly fishing literature. Nor is any of the scientific literature I have on them particularly interesting (just descriptions). Now that I've collected a few and see what unique-looking nymphs they've got, I'm really curious about them. | |
| Jason Neuswanger The Troutnut | ||
|
These advertisements will disappear if you register. | ||
| GONZO | June 17th, 2007, 12:45 pm | |
| "Bear Swamp," PA Posts: 866 | Jason, I had a chance to talk with Penn State entomologist Greg Hoover yesterday. He said that he collects most of his septentrionalis nymphs by sweeping his net through mossy breaks on 1st and 2nd order streams. He also said that when he hears accounts of unusually large (three-tailed) "sulphurs," he suspects they may be this species. Apparently they are about a hook size larger than invaria on average. He confirmed that emergence timing is about the same as the early part of the invaria hatch. (I say "early part" because invaria can extend for quite a lengthy period on streams with heavy populations. The later, smaller component is even confused for dorothea on some streams that have no dorothea population.) As you have noted, the easy field ID trait is the long spindly legs in both nymph and adult. | |
| Troutnut | June 17th, 2007, 1:15 pm | |
| Fairbanks, AK Posts: 1113 | Thanks for getting that information. :) Too bad I couldn't get a really intact dun. Still, given their rarity, I count myself lucky to have found this one. | |
| Jason Neuswanger The Troutnut | ||
| GONZO | June 17th, 2007, 9:17 pm | |
| "Bear Swamp," PA Posts: 866 | Despite the very slight reference in fly-fishing literature, I'm not sure how rare they really are. They are rather widespread in the East, being found at least from Tennessee to Maine. The name implies they are "of the nothern regions," so I wouldn't be surprised if they spread well into Canada. Even though Greg said he finds the highest populations in low order streams, the fact that your specimens came from much higher order streams indicates that at least token populations can be found in larger waters. Greg ran off quite a list of PA trout streams where he finds them, but their lesser significance compared to the overwhelming invaria populations is the reason I suggested they sometimes "support" those hatches. And even fairly bug-conscious fly fishers who encounter the hatch may not notice the differences between septentrionalis and invaria unless they collect specimens for comparison. It may just be that they are more significant on smaller streams where matching the hatch is not very important, or that their habitat requirements are narrower than the very adaptable invaria. They are a very cool and interesting mayfly, and your photos of the nymph and dun are the only ones I've ever seen. And that does make your photos rare, indeed. | |
| Konchu | June 18th, 2007, 9:22 am | |
| Indiana Posts: 199 | I'd suggest that the habitat requirements of septentrionalis may be narrower than those of invaria. | |
New features!
