Hi Jubeyjubes, this is a very interesting ant but I can't see it quite well enough to be sure of the genus. I looks like it could be the genus Lioponera (there are some pictures of a broadly similar looking ant at the link below) but for now it will have to stay a mystery. Cheers, Jon. https://www.antwiki.org/wiki/Lioponera_singularis
Thanks Jon I can easily go back and try get some more photos and better ones... They don't seem to move very fast and there were plenty of them. Watch this space!