Elongate twig ants in plant stem, La Isla Escondida, Colombia
We've seen this same phenomenon 7 years earlier in the Brazilian Amazon. These ants are nesting on a thickened part of the stem of a plant. In the Amazon, Elongate twig ants (Pseudomyrmex sp.) are known to nest like this. I'm not that sure though that this concerns Pseudomyrmex sp., as they have peculiar two-segmented waists that I'm able to match entirely.

No species identified
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