Hex Mayflies
Hexagenia limbata
The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.
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Mayfly Species Eurylophella temporalis (Chocolate Dun)
Where & when
This widespread Eastern and Midwestern species is not really mentioned in fly fishing literature. The Leonards say in Mayflies of Michigan Trout Streams that it is found in lakes and small streams. Some ready-to-emerge nymphs I collected in northern Wisconsin came from the very small headwaters of a small stream in early June, while other adults were found emerging in long, broad, lake-like flats of a warmwater smallmouth stream on June 21st.Species Range
Hatching behavior
The only emergence I've witnessed was midday on a lake-like flat on a warmwater stream. Nymphs appeared to be emerging through the surface film throughout the river, possibly more concentrated near shore.Specimens of the Mayfly Species Eurylophella temporalis
1 Male Dun
I found this specimen along with a female on the surface in the shallows of a long flat in a warm-water smallmouth bass stream, during the middle of the afternoon. There were quite a few of them on the water throughout the day, but not enough to interest trout, especially since the nearest trout were several miles away in different rivers. I held on to this one for a few days hoping it would molt into a spinner for a better chance at a positive species ID, and it finally did, so this same individual is listed as a separate specimen as a spinner.
1 Female Dun
I found this specimen along with a male on the surface in the shallows of a long flat in a warm-water smallmouth bass stream, during the middle of the afternoon. This same individual is listed as a separate specimen after molting into a spinner.
1 Male Spinner
This male spinner molted from a dun I photographed a few days earlier, as did a female of the same species that I captured with it.
It keys confidently to Eurylophella temporalis using Allen & Edmunds (1963), primarily based on the shape of the penes, which is more distinctive for this species than for most others in the genus. However, the remainder of the description of the male spinner in that paper fits this specimen perfectly as well.
It keys confidently to Eurylophella temporalis using Allen & Edmunds (1963), primarily based on the shape of the penes, which is more distinctive for this species than for most others in the genus. However, the remainder of the description of the male spinner in that paper fits this specimen perfectly as well.
1 Female Spinner
This female spinner molted from a dun I photographed a few days earlier, as did a male of the same species that I captured with it.
1 Nymph
Discussions of Eurylophella temporalis
florida mayfly nymph imitations
2 replies
Posted by Homer47 on Sep 5, 2012
Last reply on Sep 6, 2012 by Sayfu
Looks like an imitation would be about a #10 or #8 dark brown nymph pattern. I'm down here in north Fla and trying to match the hatch in the far north central part of the state, mostly to fool the bream. Any ideas or help would be appreciated. I found two patterns so far that seem to work- a little brown nymph with a rusty brown/orange thorax(maybe this is a good representation of the E. Temporalis), and a size 12 buzzer nymph with black body, peacock thorax and white breathing filament. The bream seemed to agree with that choice. I would like to try and copy more local insects as I figure out what they are.There are dragonflies and damselflies and mosquitoes. I could start there.
Start a Discussion of Eurylophella temporalis
References
- Leonard, Justin W. and Fannie A. Leonard. 1962. Mayflies of Michigan Trout Streams. Cranbrook Institute of Science.
Mayfly Species Eurylophella temporalis (Chocolate Dun)
Taxonomy
Kingdom
Animalia (Animals)
» Phylum
Arthropoda (Arthropods)
» Class
Insecta (Insects)
» Order
Ephemeroptera (Mayflies)
» Genus
Eurylophella (Chocolate Duns)
» Species temporalis (Chocolate Duns)
Species Range
Common Name
Resources
- NatureServe
- Integrated Taxonomic Information System
- Described by McDunnough (1924)