Page 1 of 1
A Key to Non-Marine Mollusc Families
Posted: Fri Dec 05, 2008 12:49 pm
by SteveMcBill
The Families of British Non-marine Molluscs (Slugs, Snails and Mussels)
The following web-page provides a key to the families of British Non-Marine Molluscs (Slugs and Snails):
http://delta-intkey.com/britmo/index.htm
Steve 
Re: A Key to Non-Marine Mollusc Families
Posted: Fri Aug 15, 2014 3:39 pm
by bankst
Hi Steve,
Somebody has dragged some old drain pipe out of the canal alongside the Brindley in Runcorn and left it on the bank. I don't know how long it's been in the water, but parts of it are encrusted with little mussels. I'm afraid I can't ID them from the key you posted, but here's a photo with dimensions.
I also recently noticed large numbers of very similar mussels on the sluice gates at the top of the Anderton Boat Lift. Obviously the gates are under water most of the time, but when they lift to let boats through, the mussels are plainly visible.
Cheers,
Tom.
Re: A Key to Non-Marine Mollusc Families
Posted: Fri Aug 15, 2014 4:09 pm
by SteveMcBill
Hi Tom,
Not easy from the picture but my guess here would be Zebra Mussel (Dreissena polymorpha). Andy Harmer has done quite a bit of work on the local canals and has found this invasive species to be widespread in our area. See here: http://en.wikipedia.org/wiki/Zebra_mussel
Many of the mussels have a distinctive zig-zag marking on the shell but not all do and those that do not can be dark in colouration (as per your photo). They do tend to be rather small though long-lived specimens can reach up to 2 inches in length (most do not). See here in the small article about them in Canada: http://news.nationalpost.com/2014/08/12 ... r-decades/
Interesting couple of records to put into RODIS - especially if you can get confirmation from Andy of the ID.
Cheers.
Steve
Re: A Key to Non-Marine Mollusc Families
Posted: Fri Aug 15, 2014 4:40 pm
by bankst
Thanks Steve, very interesting. Hopefully we can get a positive ID.
I haven't noticed any obvious anti-Zebra Mussel measures in place in the UK, but from your article, it certainly seems to be a hot topic in North America, as it is in Spain. I recently visited a reservoir in Extremadura, popular with weekend boaters, and where the Government has just constructed an elaborate boat-washing facility, specifically for the purpose of preventing the spread of Zebra Mussels, (according to the sign on the gate).
Never once saw it in use though!
Cheers,
Tom.
Re: A Key to Non-Marine Mollusc Families
Posted: Fri Aug 15, 2014 8:00 pm
by SteveMcBill
I agree with you Steve - Zebra.
Andy
Principal Ecologist
Andy Harmer Limited
Re: A Key to Non-Marine Mollusc Families
Posted: Mon Aug 18, 2014 8:03 am
by bankst
Thanks Andy.
It's going on RODIS!
Tom
Re: A Key to Non-Marine Mollusc Families
Posted: Mon Aug 18, 2014 9:26 am
by SteveMcBill
When you wrote "It" above Tom I hope you meant "They" ?? Runcorn and Anderton !!
Steve
Re: A Key to Non-Marine Mollusc Families
Posted: Mon Aug 18, 2014 9:47 am
by SteveMcBill
Thanks for putting the 'Runcorn' record for Zebra Mussel (Dreissena polymorpha) in Tom - can I request that you put the one in for 'Anderton' - assuming you know the date etc. ??
Thanks also for putting the Elephant Hawkmoth (Deilephila elpenor) larva in - appreciated !!
Steve
Re: A Key to Non-Marine Mollusc Families
Posted: Mon Aug 18, 2014 11:10 am
by bankst
Steve,
On the ball! - I knew you'd notice that I'd only recorded the Runcorn Zebras. I can't remember the date for the Anderton record, so I'll check it tonight and post a photo of them tomorrow!
Cheers,
Tom.
Re: A Key to Non-Marine Mollusc Families
Posted: Mon Aug 18, 2014 8:04 pm
by SteveMcBill
Thanks Tom.
Steve
Re: A Key to Non-Marine Mollusc Families
Posted: Tue Aug 19, 2014 8:50 am
by bankst
Here are the Anderton Boat Lift Zebra Mussels, photographed on the 12th June 2014 (this year).
I wonder if repeated exposure to air, thanks to the constant opening and closing of the sluice gates, puts these individuals at a competitive disadvantage, compared to their neighbours adhering to fixed underwater structures . . . think I need to get a life, or maybe a Ph.D.
Tom.