April 10, 2000
From: Kathe R. Jensen
Dear Carlo Magenta,
The Caulerpa you have on your photos looks uncomfortably similar to Caulerpa taxifolia, which is a pest in the Mediterranean. It has adapted its physiology to aquarium conditions (low light intensity, cool temperatures), and was accidentally released near Monaco in the early 1980s. There is a group of scientists trying to establish a total ban on aquarium trade of this alga, so you should tell the aquarium owner to be very careful about disposing of surplus algae - and certainly stop selling it! There are a number of web-pages where you can get more information about the spread and attempts to control this alga in the Mediterranean (unfortunately I can't remember them off the top of my head, but they are easy to find).
The Oxynoe may very well be the Mediterranean Oxynoe olivacea, which usually has few papillae, but usually some dark blue or brown spots - but colouration varies. Did you get a closer look at the eggs? They can at least be used to separate out one of the Caribbean species, Oxynoe azuropunctata, which has large egg capsules and lecithotrophic (non-feeding, poorly swimming) larvae.
Kathe R. Jensen
email@example.comJensen, K.R., 2000 (Apr 10) Re: Oxynoe sp from West Atlantic?. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/2244
Do you know where Caulerpa taxifolia was introduced from?