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mayfly  - Callibaetis ferrugineus - female

mayfly - Callibaetis ferrugineus - Female
Maryland City, Anne Arundel Co, Maryland County, Maryland, USA
October 9, 2009
Size: ~4.5 mm, not incl. tails
Revised size (6/24/2019). Used screening mesh size to obtain accurate size measurement.

Moved from Mayflies.

Callibaetis ferrugineus ferrugineus
Hi Jay-

I believe this female imago to be Callibaetis ferrugineus ferrugineus.

Incidentally, mayfly body length is measured from the front of the head to the end of the abdomen, and does not include any body appendages, like legs or tails. And, ~25 mm is at least twice as long as any Callibaetis species measured thusly.

Callibaetis mayfly
My measurement was totally from memory...I had had a large Maccaffertium on the same screen earlier that year.... Sorry my goof! I am very familiar with making insect measurements, incl. mayflies or whatever. Thanks for your ID. I do not see this genus on my trout streams...think they are mostly lake dwellers, if I remember correctly.

Moved from ID Request.

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