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mayfly - Baetidae - male

mayfly - Baetidae - Male
Baiting Hollow, Suffolk County, New York, USA
July 22, 2008
Size: about 5 mm
Found dead on a zinnia leaf but the eyes are so spectacular I thought it might be worth posting.
Could this be Family Baetidae?
I didn't see one there that looked like a match.

Images of this individual: tag all
mayfly - Baetidae - male mayfly for ID mayfly for ID - male


male Baetidae -- perfect shot!
you'll hopefully get it down to genus soon

I was just looking at Cloeon dipterum which appears to have a lot of variation but his one, although not to detailed, looks close.



Not Cloeon
Cloeon has only one recognized species in North America (although there seems to be an unresolved debate among European entomologists as to whether dipterum represents a species complex). The specific epithet implies that this is a "two-winged" species, and your specimen clearly has small hindwings.

The "variation" that you noticed among the Cloeon specimens actually reflects pronounced sexual dimorphism and differences between the imago and subimago stages of each sex. If you look at specimens of the same stage and sex, you'll see the similarities.

Although the shape of the hindwing of your specimen can serve to rule out a number of genera in Baetidae, I'd need a clear view of the venation of the hindwing or the configuration of the male terminalia to determine the genus with some confidence.

Thank you for the long analysis which is very informative.

I was not too interested in this little dead guy, he was too small to really see, until I downloaded the pictures and wished I had tried to pay more attention to details.

I added a larger version of what is already there but don't have any great hope of it being useful. I don't know what the male terminalia should look like, here it looks a bit mangled.

Thanks again....Lynn