Proformica sp. identification Bulgaria.

[jonathan21700]

Hello everyone and first of all sorry for posting in English, I come from Bulgaria.
So I have found this interesting specimen of a queen which I believe is a Proformica sp.
She was found in an urban habitat sometime in summer on a old spider web, sadly she is a bit damaged and her antennae are missing.
Her length is about 5 mm. There is very little information about this genus and I was not able to identify her species. I thought that you guys can help considering you have experience with such species. Another thing to me she looks very similar to Iberoformica subrufa but I am pretty sure she can't be that species because it hasn't been recorded from the East Mediterranean.
So here are some pictures, they aren't very good but that was the best I could do with a telefone camera and a lens on top.

Thank you!

[winny88]

Hi, Jonathan!

This is Formica cinerea and not a queen, but an ergatoid, which is an intermediate cast between a worker and a queen.

If you are thinking about the "strange" reddish patches, they are simply some depigmentated areas due to the fact it is an old and ruined specimen, in a bad conservation status.

[jonathan21700]

Oh that's very interesting. Never heard that F. cinerea have an intermediate cast and that makes a lot of sense now. Are you sure about that? I always though that she was Proformica. The other thing is I found two of them in one spot next to a building on two separate webs and then another one on a web in a different location in the same city. This makes me think that it should be a regularly occurrence then?
BTW, do you have pictures or do you know of some papers that I can read about this?

[winny88]

Yes, sure!

Ergatoid specimens can occur in every ant species (that have both gynes and workers) as an occasional aberration.

You can easily discard Proformica by the masticatory margin of mandibles. In Proformica the teeth are progressively increasing in length from the base to the tip. While in Formica (like in this specimen) there is the alternation of a long tooth and a smaller one.

[jonathan21700]

Thank you very much about this information! I wouldn't have figured it out myself. Otherwise I've never seen workers of Proformica in my city and it seemed to me a bit strange to be them. Thank you again!