Een libel als transporteur van een slak

The transport of molluscs by animals has been known since Darwin. For instance freshwater mussels and snails may be transported by water fowl and land snails by birds and sheep. By chance I recently photographed a groggily flying female Common darter Sympetrum striolatum. On later inspection of the picture the dragonfly proved to carry a small Gastropod on its head. Guided by the estimated ratio of length and width of the shell it is presumed to represent a juvenile specimen of the Common bithynia Bithynia tentaculata. A hypothesis is presented to explain this rare event.