Forum Entomologi Italiani

Another ant from Costa Rica. They are able to sting very painful. 3-4mm

Again Monomorium sp. ?

Sure! Monomorium sp..
To be honest I think this belongs to no-one of the three species in the checklist of Costa Rica. In fact in my opinion no-one of these three species is compatible because of the abundance of erect hairs expecially on the antennae, cheeks, gula, femurs and tibias. So I think that also the other photos of the floating raft of ants are uncertain now. A possibility that I see could be Monomorium minimum, a species known from USA, Canada, northern Mexico and sporadically in Southern America, but not yet in Costa Rica. But I'm not sure! And never discard the possibility of a new species.

To give you an idea of what I said, these are the species in the checklist for Costa Rica: http://www.antweb.org/images.do?subfami ... taricaants

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Vade ad formicam...

I notice the differences of the hairs on the head in comparison with the pictures you linked on. Checklists of latin- or south American countries often are very unreliable. Thank you again for the effort you put into my requests.