This is an image of the entrance to the nest of a species of Indian Harvester Ant. This was spotted in the hills approximately 30 km North-West of Pune, Maharashtra, India. CC BY-SA 3.0

A nest of an Indian Harvester Ant, approximately 30 km North-West of Pune, Maharashtra, India. Image by “Rushil”, shared under a CC BY-SA 3.0 license.

On the Indian subcontinent there is a species of ant with a distinct nest entrance flanked by a raised series of concentric clay rings, as though to prevent flooding. The ant seems reasonably common- at least, it is commonly photographed (see here). Locals call it a “harvester ant”. I have not seen any photographs where the ants are visible enough to identify.

The internet has two different ideas about the identity of this mystery mini-architect. One is Pheidole sykesii, which is possible, but I fear that idea may be one of those self-reinforcing internet citation circles with no verified literature behind it. The other is that this is a species of Trichomyrmex, a suggestion on twitter from several others, including at least one professional myrmecologist.

My Google-Fu has run dry, though. Do any of you know what makes these lovely mounds?

***Updates from facebook: Himender Bharti, an Indian myrmecologist, is sending students out to collect specimens. And Marek Boroweic points out older literature references to Pheidole sykesii.

***Update 2: http://www.myrmecos.net/2015/05/13/what-are-indian-harvester-ants/comment-page-1/#comment-185700