Mayfly Species Heptagenia culacantha
Taxonomic Navigation -?-
Kingdom Animalia (Animals)
» Phylum Arthropoda (Arthropods)
» Class Insecta (Insects)
» Order Ephemeroptera (Mayflies)
» Family Heptageniidae (March Browns, Cahills, Quill Gordons)
» Genus Heptagenia
» Species culacantha
This is the largest species of Heptagenia on the continent, and it's also one of the largest in the entire Heptageniidae family, being almost the size of the March Brown, Maccaffertium vicarium. Nymphs and adult females have been collected with bodies up to a size of 19.5mm, a little over 3/4" long.
Where & When
In the paper announcing its discovery, this mayfly was reported only from two very large rivers in New York and Pennsylvania, the Delaware and the Susquehanna. The authors first discovered the nymphs and duns in the Susquehanna near Three Mile Island, PA in 1980, and in 1982 they found more nymphs which they raised into eight spinners. They later figured out that several specimens collected from the Delaware and Susquehanna in 1974 belonged to this new species.This mayfly is very hard to find, even for experts who know where to look. The discovering scientists wrote, "rarely was more than one nymph found on the underside of the same rock." Their attempt to find more specimens in 1981 was unsuccessful. However, the species seems to still be around. The Mayflies of the United States geographic database shows additional records from far northeastern New York and south-central Pennsylvania.
Delaware River fishing guide Paul Weamer of Border Water Outfitters found and photographed a female Heptagenia culacantha dun in 2005, and his photos are posted and discussed in a "name that mayfly" contest on the Fly Fisherman magazine forum. I incorrectly guessed Heptagenia flavascens, but I wasn't far off the mark: Evans (1985) mentions that it is Heptagenia culacantha's closest relative.
Nymph Biology
Substrate: Underside of large rubble and boulders
Environmental Tolerance: Known mainly from a fairly warm trout river and a warmwater river
The nymphs are supposed to be strikingly colored, yellow with brown markings. I don't know of any angler who has seen one to make the comparison, but the scientific description brings to mind a color pattern similar to many of the golden stoneflies of Perlidae.Environmental Tolerance: Known mainly from a fairly warm trout river and a warmwater river
Recent Discussions of Heptagenia culacantha
Link to pictures of H. culacantha 2 Replies »
Many thanks to user Softhackle for digging up this link. I knew about the thread from back when it started, but I wasn't able to find it when I went back to look last night. Good work!
Fly Fisherman Magazine forum topic with two pictures of a H. culacantha dun.
I've added the species to the "live" part of the database and put up a rudimentary page where I can compile any more information we find.
ReplyDoes anyone know anything about Heptagenia culacantha? 8 Replies »Fly Fisherman Magazine forum topic with two pictures of a H. culacantha dun.
I've added the species to the "live" part of the database and put up a rudimentary page where I can compile any more information we find.
This is a shot in the dark, but I'm trying to track down descriptive information about a rather rare "mystery mayfly." Heptagenia culacantha was identified in 1985 (Evans, Botts, & Flowers). About all I have right now is a tease from the Journal of the New York Entomological Society--"This infrequently taken species, one of the largest and most striking North American heptageniids, is known only from Pennsylvania and New York."
The reason I'm so interested is that I believe I encounter a fishable hatch of these mayflies every season on one of my favorite PA brook trout headwaters. If that conjures a picture of fishing to 6-7" dinks, you'll need to double those numbers to appreciate how special this stream really is. Add to that an image of the fish rising to these beautiful "mystery mayflies" that hatch in the evening, following a day-long emergence of Dark Green Drakes (Litobrancha recurvata)!
It is such a special event that it is one of the very few things that can pull me away from fishing my favorite Olive Morning Dun hatch (Drunella lata, nee cornuta). Help!
ReplyAdded more Heptagenia culacantha infoThe reason I'm so interested is that I believe I encounter a fishable hatch of these mayflies every season on one of my favorite PA brook trout headwaters. If that conjures a picture of fishing to 6-7" dinks, you'll need to double those numbers to appreciate how special this stream really is. Add to that an image of the fish rising to these beautiful "mystery mayflies" that hatch in the evening, following a day-long emergence of Dark Green Drakes (Litobrancha recurvata)!
It is such a special event that it is one of the very few things that can pull me away from fishing my favorite Olive Morning Dun hatch (Drunella lata, nee cornuta). Help!
Posted by Troutnut on Dec 19, 2006
I went to the entomology library today and photocopied the 1985 paper that first described this curious species. I've updated the culacantha page with this information.
Reply
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