Burying anemone off Cathedral Rocks?

[MSilvia]

Here's a familiar-looking picture of a sponge known as Polymastia invaginata (my Latin isn't great, but am I the only one thinks whomever named it had his mind in the gutter?) http://www.guiamarina.com/chile/01 animals/01 Porifera/Polymastia invaginata.jpg

It looks right, but the site I found it on referenced it's range as "antarctic". It's either something else, something VERY far from it's recognized home territory, or the range is much less limited than previously thought.

Still, if a member of the Polymastia genus looks like this, I feel pretty secure in agreeing with RIOceanographer's colleague.

In any case, nice find! I think it would be fun to have periodic "identify the critter" games in this forum.

 

[oceancurrent]

Wow. This is a very convincing match, Matt. I found a few more pics, which support the match:

http://www.guiamarina.com/chile/01 animals/01 Porifera/Polymastia invaginata/index.html

The only problem seems to be that according to this:

http://www.vliz.be/vmdcdata/porifera/porifera.php?p=taxdetails&id=170639
http://www.vliz.be/vmdcdata/porifera/distribution.php?p=details&id=1907

the sponge only lives in the Arctic - quite far from Rockport! I couldn't find any other readings on the species. Did you find any?

 

[MSilvia]

I don't exactly have a good field guide to the sponges of the world with me, so I'm in as much doubt as to the species as you. The genus seems like a convincing match though. I'd say it warrants taking a closer look... who knows, maybe you found a new one. If so, I vote for naming it Polymastia cathedra, in honor of the site.

So far, I haven't had much luck finding a list of northern Atlantic polymastia species, but that's where I'd start.

 

[jdelprete]

I agree that it is a sponge. I took a peek through my bio books from college (bio major) and then went and did some searching online. Polymastia can look very different depending on what species it is but again from my searching looks about right. More info here:

http://www.habitas.org.uk/marinelife/species.asp?item=C2610

http://www.guiamarina.com/chile/01 animals/01 Porifera/Polymastia invaginata.jpg

My .02

Jim

 

[RIOceanographer]

There are indeed sponges of this genus in the area. I did a quick look and I found a reference listing 4 species of this genus in the Gulf of Maine:

http://www.nefsc.noaa.gov/nefsc/publications/crd/crd0407/

The species they list are are Polymastia infrapylosa, P. mammilaris, P. andrica, and P. robusta. There may be others not listed in that reference as well.

 

[oceancurrent]

I put my vote on Polymastia robusta:

http://pubs.usgs.gov/of/2000/of00-304/htmldocs/chap11/index.htm
http://pubs.usgs.gov/of/2000/of00-304/htmldocs/chap11/images/sand3l.jpg

 

[MSilvia]

Yeah... I think you may have found it!

 

[oceancurrent]

Yes. I think I am good. Thank you all for the great help