The discovery of an Antarctic epipelagic medusan in the Mediterranean

A single specimen of the Antarctic anthomedusan Russellia mirabilis Kramp 1 957 has recently been collected in the Alboran Sea. This is the first recor d for an Antarctic epipelagic organism in the Mediterranean Sea. Transport in the ballast water of a cargo ship seems the most plausible mechanism for explaining this rare occurrence. However, an alternative hypothesis is exp lored involving a possibly complex medusan life cycle together with the rol e of Antarctic (Intermediate and Bottom) water as dispersal mechanisms.