After my successful swim yesterday I decided to look at the other side of fossil beach to the east. I had heard visibility was better there yesterday. That little pocket tends to be a little clearer on average. It doesn’t seem as affected by currents circulating from the coast north and south. It was indeed clearer … but not much. Enough to make it attractive though. A few fiddler rays were nice finds. Once again I found myself distracted by the cryptic sacoglossum in Port Phillip Bay. I don’t think I’ve ever seen so many out and about.
I also discovered, for the first time in northern Port Phillip Bay (I think) a species that has been on my list of ‘want to see’. It’s perhaps one of the most amazingly camouflaged sea slugs we have. It was only properly categorised recently into a new genus.
Sacoproteus smaragdinus
In addition to the two species I saw yesterday I found two more. The best of these was one I’ve been hoping to see for ages! In the back of my mind yesterday I imagined that I’d overlooked it. I spent a good hour scouring the Caulerpa ‘sea grapes’ where they Oxynoe were feeding and it wasn’t until after almost an hour that I spotted a clump of unusual-looking weed and got very excited! This remarkable animal is still largely referred to as Sacoproteus smaragdinus and for obvious reasons it’s hardly ever seen. However, it’s recently been split into four species which means the one that occurs in Melbourne will probably be renamed. We don’t know enough yet to be sure what this one is, not that that changes anything for the animal! I’ve created the gallery to show how I initially spotted it, followed by a series of images that reveal its true identity. You can click on these to look at them in order.
In addition, there was a big Black-margined Sea-slug on the sand.
This brings the number of Sacoglossum sea slugs for the last 24 hours to five species. Their distribution is quite patchy but some of them seem to be quite locally abundant, like these rather pretty bubble snails Oxynae viridis.
Here is a picture of a large Tulip Shell. I didn’t notice at the time but there are two Elysia maoria on the sediment next to it … look just left and above right of the point. (A close up, pictured right).
