Mayfly Central Taxonomic Updates

[Taxon 0]

Mayfly Central’s North American Master Species List was updated on August 30, 2006. Thankfully, there were very few updates, and none of any consequence to fly fishers.

 

In any event, these were the updates:

 

Family: Baetidae

• Heterocloeon amplum (Acentrella ampla) - species moved from Acentrella to Heterocloeon, ending changed to conform with gender of target genus

• Acentrella barbarae - new species, Jacobus & McCafferty, 2006 [uSA:SE]

• Heterocloeon davidi - new species, Waltz & McCafferty 2005 [uSA:SE]

• Apiobaetis futilis (Pseudocloeon futile) - species moved from Pseudocloeon to Apobaetis, ending changed to conform with gender of target genus

• Heterocloeon grande (Plauditus grande) - species moved from Plauditus to Heterocloeon

• Heterocloeon rubrolaterale (Pseudocloeon rubrolaterale) - species moved from Pseudocloeon to Heterocloeon

Family: Caenidae

• Americaenis cusabo - new species, Provonsha & McCafferty, 2006 [uSA:SE]

Family: Heptageniidae

• Epeorus vitreus (Epeorus rubidus) - became subordinate synonym of Epeorus vitreus

Incidentally, I have nothing whatsoever to do with Mayfly Central. However, it is the definitive source for N. American mayfly taxonomy. Whenever it is updated, customarily once or twice a year, I compare the current version with the previous version in order to understand the specific changes. This allows me to make updates to my website, as appropriate. And, having gone to that work, I attempt to share the changes on fly fishing entomology forums.

[Joe Hard 0]

Thats some interesting changes, and the new species. Thanks for sharing!!

[Troutnut 0]

Thanks for putting that together Roger!

[Isonychia 0]

Thanks for the update, Taxon! The change in E. vitrea is the only one that might affect me -- at least this time around.

 

While we're on the subject of taxonomy, I have a question: Why did the brain trust at Mayfly Central decide to lump Stenonema fuscum, the Gray Fox, in with S. vicarium, the March Brown? I once discussed this with a Virginia Tech entomologist, who told me that the two are the same species, but differ in size and coloration because of differences it water chemistry and other natural factors.

 

If that's true, why is it possible to find them hatching from the same stream at the same time? On at least three West Virginia streams -- the Elk River, Second Creek and Hominy Creek -- I've encountered simultaneous subimago hatches of March Browns and Gray Foxes.

 

I couldn't get a decipherable answer from the Va. Tech fellow. Maybe you can enlighten me.

 

Thanks!

John

[Taxon 0]

Thanks for the update, Taxon! The change in E. vitrea is the only one that might affect me -- at least this time around.

 

While we're on the subject of taxonomy, I have a question: Why did the brain trust at Mayfly Central decide to lump Stenonema fuscum, the Gray Fox, in with S. vicarium, the March Brown? I once discussed this with a Virginia Tech entomologist, who told me that the two are the same species, but differ in size and coloration because of differences it water chemistry and other natural factors.

 

If that's true, why is it possible to find them hatching from the same stream at the same time? On at least three West Virginia streams -- the Elk River, Second Creek and Hominy Creek -- I've encountered simultaneous subimago hatches of March Browns and Gray Foxes.

 

I couldn't get a decipherable answer from the Va. Tech fellow. Maybe you can enlighten me.

 

Thanks!

John

 

John-

 

The best I can do is refer you to the following:

 

Publication: Wang, T. Q., and W. P. McCafferty. 2004. Heptageniidae (Ephemeroptera) of the World. Part I: Phylogenetic Higher Classification. Transactions of the American Entomological Society, vol. 130, no. 1. 11-45.

 

Sorry I can't provide a better answer, but don't have access the the publication.

[Ethan Bright 0]

Hi all,

 

I will try to get over to the entomology library in the next week and get that article. (I've already seen it). I will "distribute" it to those who desire it. (You can also ask Pat McCafferty at Purdue Entomology for a PDF reprint - he's great about that).

 

The fact that the two taxa are found in the same place, emerge at the same time, and differ only in patterns and color, is an indication of interspecific variation that do not represent reproductive isolation. I don't know how strong the correlation between color pattern and water chemistry is, as the Virginia Tech person implies, but McCafferty and his students and collaborators (e.g., Waltz, Kondriatieff, etc.) have done a very good documenting the variation of characters and patterns among taxa across different parts of their range. And intercorrelated with this geography are differences in temperature, chemistry, and fluvial hydrology. This has been the case with many of the speciose heptageniids, baetids, and ephemerellids. On the other hand, researchers have, over the past 30 years or so, really done a good, thorough job in studying minute details (observable only under high magnification) that permit elucidating systematic relationships. An example of this is Steven Burian's work whereby to differentiate nymphs of leptaphlebiids requires dissection and observation of details at magnifications of >100x. So, details regarding fine-scale examination of morphological characters (and its variation) are trumping casual examination of color and cuticular pattern that are known to be sensitive to stream conditions. (It's late, so I'm rambling and repeating myself).

 

When I make a copy, I'll let you know and then anyone requesting a copy can email me. (I don't think Pat would mind). Time to go to bed.

 

Ethan

[Ethan Bright 0]

OK, I have a PDF copy of the article. If you'd like a copy, just send me an email at [email protected] and I'll attached a copy.

Cheers, Ethan