Collembola and Army Ants
by
John Lattke

     In a lowland (200m) humid area in northern Venezuela with mixed pasture and forest I recently aspirated ants from a column of Neivamyrmex on the ground. Back in the lab, when I dumped the material in a petri dish for a better look, I found 9 Collembola, all very much alike (same morphospecies) except of differing sizes. The ants numbered close to 50, some were still with brood in mandibles, whilst some larvae were found floating freely in the alcohol. Most of the ants were taken from a single blade of grass no more than 12 cm long that lay flat on the ground as they walked upon it. Were the springtails prey items? None were found within ant mandibles. Some collembolans were quite small, almost too small to make worthwhile prey items, but perhaps the ants have another opinion. A fortuitous capture of so many springtails? Perhaps, but why so many in such a reduced area that was seething with army ants. I’ve had a devilish time using Borgmeier’s 1955 revision and Watkin’s 1976 keys so no ant IDs so far, but the springtails do appear to be Isotomids.