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Pteria hirundo

(Linnaeus, 1758)

David Fenwick Snr A chance and very lucky find today, a nice Atrina fragilis, Fan mussel, 12.03.13, Newlyn Harbour, Newlyn, Penzance, Cornwall. SW 46340 28580. One valve, discard into harbour. Shell valve 260 x 130mm. Disgarded with Glycymeris glycymeris, Dog cockle; Venus casina, Pale venus; and Pecten maximus, Great scallop.

Dave Rolfe Wow! That is a lucky find! Where was it discarded from? I presume a fishing boat.

David Fenwick Snr Not enough discards there to suggest that what is happening at the place where found is commercial activity, although what has been caught would have been caught commercially. Probably someone sorting through odds and ends that had somehow been brought to shore rather than dumped at sea. Common disgards were Venus casina and Glycymeris glycymeris, all in good condition and I even found a complete shell of the latter. Nice to see them there in good condition as so often there're worn after being cast up on storm beaches. I have the shell on my desk at the moment I've still not come to terms with finding it. Hoping to go back and find a nice Pteria hirundo tomorrow, I wish!!!

Dave Rolfe Good luck with that! But I asked as if you knew where the boat had fished you would have a locality. Nice to see V. casina, never found that one yet.

David Fenwick Snr Sorry Dave, don't have a locality at all, could be UK, could even be French, I can only presume the V. casina and G. glycymeris are from the same ground and are probably too common to narrow down an area from records. As a record my record might not be that useful I know, but as a find for the collection here, well pleased.

Dave Rolfe Oh yes, as a collector myself I can understand that. I would just label it as you have described.

David Fenwick Snr Will let you know if any more turn up Dave. Spent about 15 minutes going round the area where I found it, but there could be others around the harbour so well worth going just for molluscs. I went there today for anemones and anemone parasites and ended up sampling sponges as the tide wasn't as low as it could be.

Dave Rolfe I do similarly here in Kent, I am a member of the Kent Wildlife Trust's 'Shoresearch' team. I specialise in Mollusca and others each have their own expertise in different fields.

David Fenwick Snr Snap, I'm involved with Shoresearch down here as well, at Marazion Causeway next month, showing people around one of my favorite local sites.

Dave Rolfe Cool! Next month is St. Margarets near Dover. Been there before and found some interesting stuff. It is where they had a big chalk cliff fall last year.

Yvonne Beale Hello there, I'm new to the group. You get these off Orkney where I live but I doubt I'll find one unless I am very lucky too. I am very interested in byssus and have been researching it for the past month online, how it is turned into sea silk etc so please do tell if there was still any attached please as if there was I would really like to have a look at it if possible. I'm wondering if this species could also yield it to try to spin it. The only person in the world who is a Master crafter of it harvests it from the live creatures in May when the sediment softens and then carefully replants them. I ordered a book from Sweden just this month about it all and I am slowly working through it by translation. Fascinating stuff though. Sorry to jump on your post but I was surprised to see this.

David Fenwick Snr Sorry to say Yvonne but the shell in question had no threads, it was just a shell and a very clean one. I think it was a just disgard, probably trawled up by a scalloper and then used as bait by someone potting for crab or lobster. A large Islandic Cyprine was also found close-by. I'll be on the lookout for more shells at the site.

Yvonne Beale What a good one for your collection anyway, very lucky find.

David Fenwick Snr Pride of place on my office desk.

George Brown Hi Yvonne, I only know of one Atrina, which I look at regularly. There is no evidence of byssus threads as far as I can see so where are they located? I don't want to disturb it.

Yvonne Beale Here is a little video which shows the species used for this in Sardinia, Atrina nobilis. The A. fragilis is the one that you get around here and I haven't read that it can be used in the same way but I suspect it could be. The video does contain a number of innacuracties, the thread can be burnt and moths love the sea silk cloth but there is good underwater footage. The lady who harvests it doesn't harm the creatures, she replants them, so it is on the outide of the shell wafting around in the video and I think anchoring it too. http://www.youtube.com/watch?v=LhjfGRJXabo

Joanne Porter very interesting

Yvonne Beale It really is, I'm so interested in it. It has to be treated to make it look golden and this is where she is a Master.

David Fenwick Snr Just been doing a bit of digging. Couch in his 19th Century ''A Cornish Fauna'' describes various small bivalve species being trapped by the byssus of Pinna. So they do have them.

David Fenwick Snr Couch "A Cornish Fauna" - of Pinna. They stand upright, with the large end about an inch above the surface ; the lower end fixed by a very large strong byssus, so firmly attached to the gravel, that much force is required to draw them up ; and most commonly the byssus is left behind. This beard is composed of numerous, fine, silk like fibres, of a dark purplish brown, two or three inches in length.

Yvonne Beale How interesting, thank you very much for passing on that information. That was some sleuthing!

George Brown Thank you David. That explains why the byssus threads are not visible.

Message posted on British Marine Mollusca on 12 Mar 2013
Antonio Colacino Pteria hirundo on Paramuricea clavata, Archipelago of La Maddalena,North Sardinia-Italy, Mediterranean sea,depht m 26-few days ago

Ernst Andres You purchased a pearl :-)

Stuart Pearce Great shot :)

Galina Maslova Nice

Message posted on The Global Diving Community on 08 Oct 2013
Animalia (Kingdom)
  Mollusca (Phylum)
    Bivalvia (Class)
      Pteriomorphia (Subclass)
        Pterioida (Order)
          Pterioidea (Superfamily)
            Pteriidae (Family)
              Pteria (Genus)
                Pteria hirundo (Species)
Associated Species