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Newsletter - November 2010

November Meeting
Margaret Morley kicked off the evening with a reminder about the toxic seaslug Pleurobranchaea maculata which is still a potential hazard on the Auckland east coast beaches. Researchers have found it feeding on beds of the introduced Asian mussel, Musculista senhousia.

Margaret also brought in a 1950's Manukau Harbour survey document that had recently been discovered in the Museum archives. It will be very interesting to compare this to more recent surveys of the Manukau Harbour.
Margaret would like to hear from anyone who can provide the christian names and/or personal background for the following club members who took part in it ... Bill Lee-Pike, H.J. Chapman, Mr and Mrs W.P. Thomson, Grant Bawden, P. Hutton, Mrs J. Wyatt, Stan Turner, A.H. Jones, & Mrs A. Morgan.
She would also like to find out who compiled the survey document. If you can shed any light on this please contact Margaret at mmorley@aucklandmuseum.com or phone (09)5768323.

Our attention then turned to the main subject of the evening - New Zealand volutes.
Peter Poortman spoke on this subject, and also brought in some trays of his best NZ specimens.
Volutes are a very popular family with collectors because of their beauty, variety, and large size.
The Volutidae family is enormous worldwide, and New Zealand is well represented with 25 recent species currently being recognised. Twenty-one of these species belong to the genus Alcithoe, all of which are endemic to NZ. Besides Alcithoe we have Provocator mirabilis and Zygomelon zodion which are also both endemic to NZ. The other two species, Lyria insignita and Calliotectum egregium are found at the Kermadec Islands, but only the Lyria is endemic to NZ.
Only one species of Alcithoe (Alcithoe aillaudorum) is found outside NZ waters - just south of New Caledonia.

Peter gave an overview on the location and identification of each NZ species, noting that the location where a shell was collected can aid greatly with it's identification.
We are fortunate to have some excellent literature available on NZ Volutidae. In particular ...
. "New Zealand Mollusca", by A.W.B. Powell. Published 1979
. "Cenozoic Mollusca of New Zealand", by A.G. Beu and P.A. Maxwell. Published 1990
. "The Recent Volutes of New Zealand", by Patrice Bail and Allan Limpus. Published 2006
. "New Zealand Seashells Visual Guide", by Jenny Raven and Selwyn Bracegirdle. Published 2010
But even with these resources it is sometimes still difficult to positively identify some shells. Peter has several Alcithoe specimens that he cannot identify, and said that there was no shame in just listing such shells as "sp." if you are not sure about their identity. What matters most is accurate data.

While much work has been done on NZ volute taxonomy, it is still very much a "work in progress".
Over the years there have been a lot of changes. For example ...
. our Leporemax, Pachymelon, Palomelon, Teremelon, & Waihaoia are now synonymised into genus Alcithoe
. depressa, motutaraensis, swainsoni, elongata, rossiteri, & pacifica are now synonymised into species arabica
. haurakiensis, hedleyi, gracilis, & subplicata are now synonymised into species fusus
. calva & johnstoni are now synonymised into species jaculoides
. grahami, smithi, & chathamensis are now synonymised into species wilsonae

Many of our recently described Alcithoe have been based on a very small number of specimens. For example ...
. Alcithoe triregensis was described from just one specimen
. Alcithoe fissurata elegans & Alcithoe colesae were each described from just two specimens
. Alcithoe albescens, Alcithoe davegibbsi, & Alcithoe fissurata crassa were each described from less than a dozen specimens

So it's very unlikely that any of us will be able to collect a complete set of Alcithoe!
Many of our species are restricted to deep water, and with increasing controls on bycatch, the fishing industry has virtually dried up as a source of shells for collectors.
And it is difficult for many of us to keep up with all the taxonomy changes in the last few decades. Peter estimated that up to 25% of NZ volutes in private collections are likely to currently be misidentified.

Our NZ volutes are unique and very interesting. For example, here is some trivia about Alcithoe benthicola ...
. the name "benthicola" relates to it's very deep water (benthic) habitat.
. the distinctive circular marks on the body whorl are due to the attachment of egg capsules - a behaviour unique to this species.
. a dwarf population (130-140mm adult size) exists off the Poor Knights Islands at a depth of 700m.
. surprisingly, this species is most closely related to Alcithoe flemingi.
. and speaking of Alcithoe flemingi, for some reason it is typically found with the protoconch broken off.

After all the talking we then put some of this knowledge to practice by identifying several Alcithoe specimens brought in by Luen Jones.

After supper we were given an NZ shell identification quiz by Margaret, and throughout the evening we had access to a large selection of library books which were kindly brought out by our librarian Gladys Goulstone.

Next Meeting - Annual General Meeting
202 Gillies Avenue, Epsom at 7:30pm on Tuesday 14th of December (doors open at 7pm)
We will meet in the large room for our last meeting of the year - the AGM and Christmas party.

We will commence with the AGM.
Annual reports will be presented, club issues will be discussed, and officers for the coming year will be elected.
This is your chance to have a say in the running and future direction of the club, so we encourage all members to attend. If you would like to put anything on the agenda then please contact our club Secretary or President.
We will need to elect a new Treasurer and a new Porieria Editor. Please support your club - if you have the time and the skills for either (or both) of these positions then we would like to hear from you.

After the formalities have concluded we will enjoy our traditional Christmas supper and lucky shell dip!
This time, instead of a guest speaker we would like everyone to participate by bringing in some shells, and briefly telling us something about them.
All are invited to come and enjoy the convivial atmosphere, and we would especially welcome members who have rarely or never attended our meetings.

What to bring ...
- some shells with an interesting story
- a plate to share for the Christmas supper
- a gift wrapped shell (marked NZ or WW) for the lucky dip

New Zealand Shell Show 2011
The Wellington Shell Club invites you to the next New Zealand Shell Show in Wellington at the Lower Hutt Town Hall from 12th to 13th February 2011.
The show will cater for most classes of molluscs and levels of collector. Dealers are very welcome and sales and trading tables will be available at the venue.
Shell show program, classes, rules, and entry form, as well as some information on transport and accommodation is now available from the Wellington Club's website at: www.clublist.co.nz/sites/wellingtonshellclub.aspx.
For assistance or information please contact the Wellington Shell Club secretary Deirdre Standish at deirdre.standish@clear.net.nz, phone 64-4-9041080, or write to: 4 Sharda Grove, Paraparaumu Beach 5032, New Zealand.

Club Library
We have an extensive collection of books, magazines, and scientific publications available, as well as a biological microscope.

Other Club News
. Enclosed is some holiday reading for you Poirieria Volume 35. Many thanks to all who contributed the excellent articles.

. Best wishes to everyone for Christmas and the New Year!!

kelpbar

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