Tiny Mayfly ID help please.

[quagmireage]

Hi folks.
I found this nymph in the Keystone Select section of Laurel Hill Creek, Somerset county PA. It's really small(20-24, maybe smaller). Sorry to be so vague. If anyone has an idea what it might be, I'd love to know.


Thanks!

 

[outsider]

Baetis perhaps, but it is rather light in color. Stream chemistry can affect the colors of insects.

 

[quagmireage]

Thanks.
The color is what really threw me off.

 

[dryflyguy]

I've seen Baetis colored pale yellow like that.
However, they only have two tails - the one in your picture looks to have have three.
Blue Quills have three. But I've never seen them that pale colored.

Hmmmmmm........

 

[afishinado]

dryflyguy wrote:
I've seen Baetis colored pale yellow like that.
However, they only have two tails - the one in your picture looks to have have three.
Blue Quills have three. But I've never seen them that pale colored.

Hmmmmmm........

Your a dryflyguy not a nymph man. Baetis duns have 2 tails while baetis nymphs have three with a small middle tail like the OP pic.

The small size and light color may be attributed to a immature specimen not ready to hatch for several months.

 

[Fly-Swatter]

Freshly molted subvaria nymph? If so, they should hatch in the next few weeks. Was this specimen collected in the Fall?

 

[quagmireage]

I collected this one only a few days ago.

 

[Dave_W]

Agree - it's a little BWO nymph (Baetis).

 

[redietz]

afishinado wrote:

Baetis duns have 2 tails while baetis nymphs have three with a small middle tail like the OP pic.

The small size and light color may be attributed to a immature specimen not ready to hatch for several months.

You're actually both right. Some baetis nymphs have two tails, some have three. In fact, two of the more common species are B. tricaudatus ("three tails") and B. bicaudatus ("two tails"). The former are more common around here, though.

The light color may indicate a freshly molted instar.

 

[dryflyguy]

Well yeah - I've never really paid any attention to nymphs.
But knew the duns have two tails. And just kinda figured the nymphs would too.

That third tail is pretty stubby though.
Sort of a semi - tail

 

[quagmireage]

Thanks for all the feedback!

 

[afishinado]

redietz wrote:

afishinado wrote:

Baetis duns have 2 tails while baetis nymphs have three with a small middle tail like the OP pic.

The small size and light color may be attributed to a immature specimen not ready to hatch for several months.

You're actually both right. Some baetis nymphs have two tails, some have three. In fact, two of the more common species are B. tricaudatus ("three tails") and B. bicaudatus ("two tails"). The former are more common around here, though.

The light color may indicate a freshly molted instar.

The OP captured the nymph in PA. The two tailed bicaudatus is a western species > here

Anyway, little doubt it is a Baetis. Probably an immature (small) and freshly molted (light colored) specimen.

 

[redietz]

afishinado wrote:

The OP captured the nymph in PA. The two tailed bicaudatus is a western species > here

Anyway, little doubt it is a Baetis. Probably an immature (small) and freshly molted (light colored) specimen.

I agree on both counts. My only point was that one way of distinguishing various baetis nymphs is by counting tails. (There are plenty of other species besides the two mentioned.)

 

[afishinado]

redietz wrote:

afishinado wrote:

The OP captured the nymph in PA. The two tailed bicaudatus is a western species > here

Anyway, little doubt it is a Baetis. Probably an immature (small) and freshly molted (light colored) specimen.

I agree on both counts. My only point was that one way of distinguishing various baetis nymphs is by counting tails. (There are plenty of other species besides the two mentioned.)

Anyway, the point I tried to make is Baetis nymphs do not necessarily have two tails like the duns. In fact the most common Baetis nymphs found in PA and in North America has three tails and is the Baetis tricaudatus. I dug a pic which matches perfectly (below). Here is some info on the insect from Troutnut

Trying to ID insect species by pics or even having the actual specimen is pretty haphazard without a microscope and a book of ID keys. It's probably best to stop at the genus > Baetis


For the OP the answer of Baetis or even more generic BWO should suffice.