Suberites ficus

George Brown V83, Scapa Flow sponge. I think Becky may have posted a photograph of this very distinct sponge a few days ago but here are a few more. And no I didn't collect a sample but can do, in December, if required. Water depth 12 metres on the underside of hull.

Joanne Porter yes i'd like to know what that one is too George Brown

George Brown In Habitas, Bernard, referring to Suberites carnosus, mentions that "On the Continent a variety of forms have been recognized, graduating from thin sheets and cushions to massive-lobose and even branching forms". It feels and looks like the surface of S. carnosus/ficus. But, hey, I'm a civil engineer! :o)

Bernard Picton Yes. It does look like the Suberites ficus form which grows on Queen Scallop shells. Latest estimates for sponges though is 8000 named and 18000 not named yet. So I'd say Suberites sp.

George Brown Wow, thank you Bernard. Only 10,000 to go then?

Bernard Picton No, a staggering extra 18,000! The N E Atlantic is quite well known, but many parts of the world are hardly started yet.

Bernard Picton Appeltans W, Ahyong ST, Anderson G, Angel MV, Artois T, Bailly N, Bamber R, Barber A, Bartsch I, Berta A, et al. 2012. The magnitude of global marine species diversity. Current Biology 22: 1â€"14.

Jim Anderson Is this Suberites carnosus? Loch Nevis, 30 September 2012, 75 mm dia, 14 m depth. There were many of a similar colour with sizes from marble to tennis ball size throughout this dive

Becky Hitchin And an associated question - Habitas says that S. carnosus forms a fig shape with a short stout stalk. How likely is it that the stalk can be seen? Does it generally go back through turf etc so that you couldn't see or feel it?

Bernard Picton I think this is more likely to be Suberites ficus, Jim. In my experience S. carnosus is always a cream to brown colour, not orange to red. I'm a bit suspicious that S. ficus may include several species though, but that's the present state of sponge taxonomy for you. In S. carnosus there is usually a very small attachment, sometimes a substantial stalk if it is in mud attached to a buried shell or stone.

João Pedro Silva From this morning's dive. Appears to be the same me and Gonçalo Calado found by the end of January (http://www.flickr.com/photos/jpsilva1971/6751608437/). I think it's relatively safe to say this sponge is its prey.

Bernard Picton Did you get a bit of the sponge João? If it was here I'd say Mycale rotalis, based on colour and surface appearance. Geitodoris planata seems to eat Mycale similaris in Strangford Lough, but Mycale rotalis in some other places. I guess it could be a red variant, you get that in Doris pseudoargus feeding on red Suberites ficus (assuming that it really is D. pseudoargus, A & H named it D. flammea).

João Pedro Silva I didn't collect it, Bernard. Although I can find the exact spot (to the cm) where it is. This is in a small wreck just outside the Sesimbra harbour.