Sunday, 31 March 2013

Bothriomyrmex corsicus

Bothriomyrmex corsicus worker
It's been a long time since I've posted anything (the effect of getting married and renovating a house). I thought that this was worth breaking a three year habit.

By all accounts, Bothriomyrmex species seem to be pretty uncommon, so I'm pleased that the first one I found is the second, not the first, most common in Europe. Bothriomyrmex taxonomy was in a very confusing state, so these specimens previously keyed out as B. menozzii, but thanks to Seifert (2012) the picture is clearer. I can now say with certainty that they are B. corsicus (Seifert could not find B. laticeps type material, but my specimens didn't fit Emery's (1925) description of laticeps anyway, based upon the length of the antennal segments).

The European species of Bothriomyrmex are temporary social parasites of Tapinoma species. It is likely that invading queens of all Bothriomyrmex species kill the host queen, decapitating them with specialised mandibles, after which they become very physogastric (i.e. they swell with eggs).

I didn't collect any B. corsicus queens, but did collect a male. Unfortunately, the male was a bit mangled when it came out of the tube and did not mount very well, so wouldn't make a good photomontage.

These ants were found under a stone in south-facing subalpine grassland near Venanson, in the Alpes-Maritimes, France, not very far from other locations listed by Seifert (2012). What was perhaps most interesting was that the stone also covered a very large colony of Solenopsis fugax. This suggests that the S. fugax may have been stealing brood from the B. corsicus. S. fugax is known to raid Formica (Serviformica) and Lasius nests, and I have found them alongside Camponotus ligniperda, but I wonder whether there are any records of them stealing brood from Bothriomyrmex or any other Dolichoderine ants.