Polymastia penicillus

Paula Lightfoot Is this Polymastia? What is the situation with Polymastia penicillus and P. mamillaris? Habitas says P. mamillaris is found in Scandinavia but not Britain and Ireland, but MarLIN says it's common around the British Isles. There are more records of P. mamillaris than P. penicillus on the NBN Gateway. Is it possible to ID this to species level from a photo or should I record it as Polymastia sp (or is it something else entirely!?). We also saw some yellow ones.

Paula Lightfoot I think they are both accepted names for different species (on WoRMS), but one species isn't found in the UK. But if that's the case should we change old records of P. mamillaris to P. penicillus or Polymastia sp or just leave them? I'll post a photo of the yellow one!

Becky Hitchin Chris Wood asked us to change our P. mammilaris to P. penicillus for recent seasearch data, so maybe that's the seasearch decision at least!

Erling Svensen Anybody that have Chris Woods email? I am waiting for his new book....

Becky Hitchin chris@seasearch.org.uk :)

Erling Svensen Thanks. Got it....

Kate Lock This is the group that Christine Picton (Morrow) is researching I do believe so worth checking with her and Bernard Picton what the current status is.

Claire Goodwin There was a mix up whereby the two species were synonymised for a while so in the past UK specimens were erroneously referred to as P. mamillaris (see Christine's paper here if you really want to get into it http://www.marinespecies.org/porifera/porifera.php?p=taxdetails&id=170654). P. mamillaris is a valid species but more northern and P. penicillis is the one we get here that looks like this - it is possible to ID with confidence from a photo (see Habitas for characteristics). The other common species is P. boletiformis (the hedgehog sponge). A word of warning though - there are several other rarer species of Polymastia and several which have not yet been described so if you see anything odd looking best to just put Polymastia sp. Christine currently is working on some of these.

Tony Gilbert Tending towards Polymastia penicillus for this sponge. Ruecallan Arch, 28m, North Wall Rathlin.

Tony Gilbert Thanks Dawn. Just read up on Ciocalypta penicillus, this image has many characteristics of that, thick walls, slightly conical, colouration. But the basal cushion - in this case - am racking my brains, but think it was on the inside arch walls - it wasn't on sand or gravel - but then again the arch is a microcosm anyway.

Claire Goodwin If it was Ciocalypta penicillus you should be able to see spicule columns up the middle of the papillae and the papillae would be very neat and conical looking - also tends to be on sand and gravel not rock. We don't tend to get this much in NI either as it is more southern - although we do have a record off the Skerries. This is a Polymastia or Sphaerotylus but there are several species of undescribed Polymastia that Christine Morrow is working on and it could be one of these (sorry Dawn Watson!).

George Brown Hi. A few months ago I posted a photo of Ciocalypta here.http://www.facebook.com/photo.php?fbid=3864781990742&set=o.341487989207852&type=3&theater

Tony Gilbert That's true Dawn, good to have a forum like this then :-) I can email a higher-res version if anyone want to take a closer look, and think its on the vertcial inside wall of the arch. So should be easily found again.

Craig Muirhead redirected from NE Tunicata (thanks George Brown :)) Loch Leven, Scotland 04/08/13

David Kipling Ah but which one, there's that tapering one with the ridge line and then the other less tapering one ...

David Kipling It's one we sometimes argue about, as the tapering one isn't always as tapering in all the chimneys as you'd like...

Holly Latham Are you arguing between Polymastia penicillus and Ciocaylpta penicillus...? I would go with P. penicillus - lacking the central core, wrong texture and quite delicate. But then there could be something else... It is a strange shape (the base is not rounded) but that could presumably be influenced by its surroundings. Are there any others you are thinking of?

Richard Yorke What about Polymastia agglutinans? It was suggested I should call this Polymastia cf. agglutinans which was taken at around 20m on Lullworth Banks, Dorset July 2012

David Kipling We weren't arguing, I was just making sure in my mind why it wasn't the next-nearest species (always a good question to ask explicitly). Although Holly you're right that it doesn't feel the same as the ones we gets in Pembs, although local conditions etc etc.

Holly Latham Arguing is indeed a harsh way of putting it... I was not insinuating hand bags at dawn, more a thorough discussion of the relevant characteristic features of the species! ;)

David Kipling lol! Me and Dawn and handbags, now there's an image. No, what I meant was that I wasn't disagreeing with Dawn, just wanted to hear why it wasn't the other one that looks the same (a bit like when your maths teacher made you "show the working" for extra points).

Claire Goodwin Hate to throw a spanner in the works (to add to Dawn's brick) but there are quite a few as yet un-named species of Polymastia within diving depths which Christine Morrow is currently working on. This does look a bit different to P.penicillus (the base cushion is un-silted which is odd) so I wouldn't be 100% sure it is that. You can definitely tell it apart from Ciocalypta penicillus as (as said above) as it lacks the central column of spicules up the papillae and the papillae aren't tapered to a point.

David Kipling Do we need to send Craig back to get a sample Claire?

Claire Goodwin Of course :).

Holly Latham Thanks for confirming my fears Claire... any good resources for current info on alternate Polymastia species?

Claire Goodwin Not until Christine gets her paper finished....

Nick Owen Oooh. Paper on Polymastias, Lovely! Yes please. Any chance of a notification when it comes out please? Re Polymastia agglutinans: Didn't I read somewhere that "agglutinans" refers to its habit of binding particles to its basal cushion so that it can't be "wafted" clean? Just like Richard's pic... Note also that Richard's has closed papillae - seem to recall this is also a charachter of Pol agg.

Craig Muirhead ...and this? Loch Leven, Scotland 04/08/13

George Brown Hi Craig, is that not a sponge? Loch Leven does churn up weird stuff though.

Craig Muirhead Thanks George. I'll post it on NE Porifera

Jade Berman Definitely a sponge I would say Polymastia mammillaris although the base is not too covered...

Bernard Picton Name change, Polymastia penicillus now, Jade!

Jade Berman True must keep my names upto date... See you soon Bernard

Darryl Mayer Hi guys and gals. Me again... Is this Polymastia penicillus? Loch Creran, 10m.

Claire Goodwin Hi Darryl. I can see why you might think that but this is Leucosolenia sp. a calcareous sponge. It is much smaller than Polymastia. Polymastia penicillus also tends to have silt over the basal cushion the papillae come from and its papillae are never branched.

Darryl Mayer Many thanks Claire I can see the branching now that the specs are on... ;-)

Darryl Mayer Hi guys and gals. Me again... Is this Polymastia penicillus? Loch Creran, 10m.

Claire Goodwin Hi Darryl. I can see why you might think that but this is Leucosolenia sp. a calcareous sponge. It is much smaller than Polymastia. Polymastia penicillus also tends to have silt over the basal cushion the papillae come from and its papillae are never branched.

Darryl Mayer Many thanks Claire I can see the branching now that the specs are on... ;-)

Paula Young Hello all, Can anyone help me ID this (perhaps one for David Kipling or Becky Hitchin)? I initially thought they were squirts of some sort (possibly Ascidiella), but think it's more likely a sponge? I can't see a second siphon if they are squirts. I then thought it might be Sycon ciliatum, but it just doesn't really look like others I've seen. Any ideas? They were off Dover, about 8m down on silted chalk and about 1/2 inch long.

David Kipling Are you coming on the squirt course Paula?

Becky Hitchin Yes she is!

Paula Young I did wonder about Polymastia too, but didn't think we had it in this bit of Kent - Becky might remember...?

Jade Berman I would agree with Polymastia penicillus.

Becky Hitchin Yep, Polymastia is in Kent, lots of records from Seasearch dives

Paula Young Hurrah...Polymastia it is then! Thanks all you lovely Seasearch peoples!