Sorry to ressurect this thread - but I love ants.
Crazy hard to try and figure out the exact species, as the sheer number is crazy. I presume you were saying Mediterranean region?
I don't think it's a banded sugar ant. The gaster suggests otherwise based on the picture.
I think going based off of
- A black head
- A reddish-brown thorax (the middle section of the body)
- A black gaster (the rear section of the body
And being based in the Mediterranean region, I think, will be Camponotus lateralis. Notably, a worker. It's a carpenter ant. They can, and will bite, but not overtly common to bite. No stinging.
With you mentioning that there are some smaller, and bigger ones, it seems more likely. You tend to have a various polymorphism within carpenter ants. Such as;
- Workers (Minors) - What you've shown in your picture
- Majors (Soldiers) - Physically larger, more robustly built.
- Supermajors (Large Majors/Soldiers) - Even bigger, and absolute units. These tend to be very large, the size of the queen even, alongside having exceptionally developed heads, and mandibles.
Not the exact same colouring (As Ant colouring can change between nests, even if the exact same species), but this picture shows some of the different types.
You have;
- Worker (Far left)
- Queen (largest)
- Very far right (Super major)
- Slightly to the left of the super major, a standard major.
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