| |
| MOLLUSCAN
FORUM: 7TH NOVEMBER 2002 |
ABSTRACTS OF PRESENTATIONS (in alphabetical
order of presenters)
CHRISTIAN
ALBRECHT1
(with: THOMAS WILKE2, KERSTIN KUHN1, & BRUNO STREIT1)
1Department of Ecology and Evolution, J.W. Goethe University Frankfurt,
J.W. Goethe University, Siesmayerstr. 70, D-60054 Frankfurt, Germany,
2Department of Microbiology & Tropical Medicine, The George
Washington University, Ross Hall, 2300 Eye Street NW, Washington
DC 20037, USA.
email: Christian.Albrecht@zoology.uni-frankfurt.de
Anatomical
and molecular character evolution in the Basommatophora: conflict
or congruence?
The Basommatophora
represent a large group of predominantly limnic gastropods. They
comprise about 15 families with several hundred assigned species.
Many of them are of considerable importance for freshwater ecology
and human health. Yet, systematics, phylogenetic relationships
and character evolution are controversially discussed and poorly
understood.
In order to compare the performance of anatomical and molecular
datasets and to study the degree of their congruence, we analyzed
80 soft body and shell traits as well as sequences of the COI
mtDNA and 18S rRNA genes from the type species of 32 basommatophoran
genera involving 10 families.
Whereas the two genetic markers yielded rather well resolved
and congruent phylogenies, a cladistic analysis of the anatomical
data resulted in an unresolved polytomy. A comparison of phylogenetic
signals showed a significant signal in the molecular dataset.
However, the phylogenetic signal in the anatomical dataset
was not significant, possibly indicating a high degree of
homoplasy and background noise. We then mapped
the anatomical character-states on to the molecular phylogeny,
which was generated fromthe combined COI+18S dataset. The
results show that many characters "evolved" independently,
supporting the hypothesis of extensive homoplasies in the
anatomical dataset. In order to find those anatomical characters
that statistically discriminate among higher basommatophoran
taxa, we performed discriminant analyses (DA) with DNA lineages
as a grouping variable. Only few anatomical characters were
retained in the DA. These characters and the problem of homoplasy
are discussed in the context of basommatophoran evolution.
**
ALEX BALL
Electron Microscope Unit, The Natural History Museum, Cromwell
Road, London SW7 9BD, UK
email: a.ball@nhm.ac.uk
Specimen collection
and preparation techniques for electron microscopy
Ideally specimens
for electron microscopy (EM) should be fixed whilst still alive,
the specimens should then be processed as rapidly as possible,
a process usually requiring full laboratory facilities including
access to chemicals, refrigerators, balances and fume cabinets.
This is not always possible during extended collection trips or
when collecting in remote areas. However, with some forward planning,
it is possible to collect and fix materials for EM with no laboratory
facilities at all.
Careful planning is the key to successful collecting and with
a little forethought you can minimise the reagents you need to
take with you and assemble the materials required when you arrive.
Minimal amounts of fixatives can be taken as pre-measured aliquots.
Buffers can be taken as pre-weighed powders which only require
reconstitution with distilled or de-ionised water. Samples can
be successfully cleaned, relaxed and fixed with the bare minimum
of facilities.
Many of the supposed "rules" of EM preparation are designed
to minimise preparation time rather than to optimise the results.
For relatively small samples, representative examples of different
tissues or even whole dissections can be fixed entire and maintained
in fixative for extended periods whilst still yielding excellent
results.
A variety of basic advice (including how to work safely) will
be presented, together with protocols useful for relaxing, fixing,
decalcifying and cleaning specimens. In addition some examples
of best practice for mounting and preparing samples for SEM and
TEM will be discussed.
**
RON CARR
9, The Mallows, Maidstone, Kent ME14 2PX, UK.
email: RONCARR200@aol.com
The role of
taxonomy in distributional mapping- one example of an overlooked
species
The modern
grid-square distributional survey of British land and freshwater
Mollusca was launched by the Conchological Society in 1961,
an interim atlas being published in 1976, followed by a revised
version in 1999. Despite the enthusiasm reflected in the surveys,
long-established taxonomic changes introduced by continental
aythorities have largely been ignored by British malacologists.
The taxon formerly regarded as Lymnaea palustris (Muller,
1774) has been shown to include a second, anatomically well-defined
species Stagnicola fuscus ((C.Pfeffer, 1821). On
the basis of available information, this second species would
appear to be the commoner of the two.
**
ISTVÁN
CZICZER1
(With: SÁNDOR GULYÁS1 and IMRE MAGYAR2)
1University of Szeged, Department of Geology and Paleontology;
H-6722 Szeged Egyetem u. 2-6.
2MOL Hungarian Oil and Gas Company; H-1039 Budapest Batthyány
u. 45
email: cziczer@yahoo.com
Palaeoecological
and sedimentological investigations on the fauna and deposits
of the Tata brickyard
The prodelta,
delta slope deposits of the Szák Claymarl Formation
from the Miocene Lake Pannon are exposed in the pits of the
Tata brickyard. The deposits of the brickyard are composed
of silty clay, claymarl with very thin sand and at some horizons
intercalations of highly limonitic coquinas with the broken
shells of a typical shallow water fauna. The deposits are
highly fossiliferous with a dominance of malacofauna. According
to the latest stratigraphic classifications they belong to
the Congeria cjeki-Congeria zagrabiensis
biozone. The absolute age of the deposits is around 9.5 MA.
There is a dominance of bivalves in the fauna with Congerias
being the most frequent species [Congeria cjeki
M. Hörnes, Congeria partschi Cjek
and in the coquinas of storm deposits Congeria ungulacaprae
(Münster)]. The second richest group is that of Limnocardiids
which will possibly yield a lot of new endemic species in
the future. Furthermore endemic deep-water Pulmonates are
also present with the dominance of Planorbids, Radix
and its descendants the endemic flat, plate-like Valenciennius.
Our work is supported by OTKA Grant T029342.
**
FIONA
GILL
12, Ashdell Road, Broomhill, Sheffield S10 3DA, UK.( Earth
Sciences, University of Leeds)
email: fgill@earth.leeds.ac.uk
Fossil cold
seeps in the Caribbean
Cold seeps
are fascinating and unusual environments. They are populated by
distinctive communities of animals, many of which derive their
nutrition from chemosynthetic endosymbiotic bacteria. Cold seep
communities, both modern and ancient, are found in a range of
geological settings, on both active and passive plate margins.
However, the biogeographic distribution of modern cold seep fauna
is presently poorly understood. This project seeks to explain
the distribution of modern seep animals by examining a series
of Tertiary cold seep sites in the Caribbean region. This area
is particularly significant because, prior to the raising of the
Isthmus of Panama (3Ma ago), the Caribbean Sea provided a direct,
open water link between the Atlantic and Pacific Oceans.
**
ANNA HOLMES
National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK.
email:Anna.Holmes@nmgw.ac.uk
Conservation
Genetics of Margaritifera margaritifera (freshwater pearl mussel)
in the British Isles
The freshwater
pearl mussel (Margaritifera margaritifera) is an
endangered species in Britain and is threatened throughout
most of its European range. The family is markedly conservative
throughout its long evolutionary history (Cretaceous &
Recent) with no more than 6 extant species recognised. Given
the rapid decline in population size, conservation measures
could include translocation of individuals as re-introduction;
although in those cases where this has been attempted there
has been little success. Therefore, there is a need to understand
the genetic separation of populations before further experiments
are undertaken.
A pilot study involved three Irish, three Welsh and three northern
English populations. Two of the Irish populations showed good
separation. The results showed long tree lengths (large amount
of variation) for the Irish populations and short branched for
the northern England and the Welsh populations. It has been hypothesised
that the genetic separation may be due to population longevity
related to Pleistocene extinctions - both Irish populations inhabit
rivers not affected by the last glacial maximum. The pilot project
has been expanded to encompass the north-east of England, south
Wales, France, Czech Republic and Austria. Using RAPDs (Random
Amplified Polymorphic DNA) allows comparison within and between
populations and has previously been proven as a positive methodology
to show intraspecific variation. In addition, this report aims
to provide further information as to the re-population of those
rivers covered by ice in the last glacial period . Were they re-populated
via the east of England from Europe or from the glacial refuges
in the west and over Scotland?
**
RICHARD KENNEDY
(with: DAVID SMYTH, and DAI ROBERTS)
School of Biology and Biochemistry, Queens University, Belfast
BT9 7BL.
email: c/o: d.roberts@Queens-Belfast.ac.uk
Restoration
of native oyster beds in Strangford Lough, Northern Ireland
Strangford
Lough historically had a productive Ostrea edulis fishery
supporting up to 20 boats in oyster dredging although by 1903
oyster fishing in the Lough had effectively ceased1.
Although growth trials of oyster spat in the Lough in the
1970s produced favourable results for both O. edulis
and C. gigas, oyster aquaculture developed using
C. gigas. Between 1997-99 an EU funded project led
by fishermen was started to re-establish a sustainable native
oyster fishery in the Lough. The 1997-99 project involved:
Laying clutch and seed and re-laying native adults.
Estimating oyster and cultch densities monitoring oyster
larval densities and spatfall in summer and autumn.
Results
Investigations into native beds revealed natural cultch
cover between 0 and 70% and low densities of oysters (1-2 1000m-2).
In contrast, densities of O. edulis on commercial
mats ranged between 66 and 100 individuals m-2.
Larval densities peaked in August and September and were
highest in outflows close to commercial stock embayments.
Output: as
a result of the 1997-99 project fishermen have started to take
the first harvest of native oysters from Strangford Lough for
nearly 100 years. Proposed research. The current project will
undertake: benthic and intertidal surveys to ascertain the
current state of O. edulis stocks. Plankton surveys August
2003 for comparison with 1998 data. Investigation into
predatory impact on developing spat. Comparison of the
biodiversity of established undisturbed beds and fished beds.
1
Kennedy, R.J., and Roberts, D. 1999 A survey of the current status
of the Flat Oyster Ostrea edulis in Strangford Lough.
Biology and Environment: Proceedings of The Royal Irish Academy,
99B, 79-88.
**
LAURENCE KISS
Institut Méditerranéen dEcologie et de Paléoécologie,
Equipe Ecologie du Paysage, Case 461, Faculté des Sciences
et Techniques de St Jérôme, 13397 Marseille CEDEX
20, France.
email: laurence.kiss@univ.u-3mrs.fr
The impact
of fire on land snail communities in calcareous Provence
Fire is a
major disturbance within Mediterranean ecosystems in Southern
France and has drastic consequences for the less mobile fauna.
Numerous papers deal with the impact of fire on the Mediterranean
fauna, but no study has ever been performed on land snails, although
they are good indicators of this impact. Land snails live, for
the most part, on vegetation or in litter; their ability to escape
is minimal, and they are very sensitive to desiccation. Thus,
snails are directly exposed to fire, and also to the destruction
of their microhabitats. Moreover, their capacity for active dispersal
is generally low. The aims of the present study were (1) to define
the short-, middle- and long-term impact of fire on the species
richness and diversity of land snail communities, (2) to clarify
the consequences of successive fires at relatively short intervals
(less than 25 years) on malacofaunas, and (3) to reveal the pattern
of post-fire recolonisation within these communities. Despite
a drastic reduction in abundance in the first years after a fire,
Mediterranean land snail communities seemed to show a high resilience
to fire, provided the interval between successive fires exceeds
ten years. Patterns of post-fire recolonisation were not really
clear; post-fire snail communities seemed to depend on the structure
of pre- and post-fire habitats, and also on numerous and scattered
refuges provided by varying fire intensities within a site.
**
TOMASZ K.
MALTZ.
Museum of Natural History, Wroc?aw University, Sienkiewicza 21,
50-335 Wroc?aw, Poland.
email: via: bepok@biol.uni.wroc.pl
Life cycle
of Helicodonta obvoluta (O. F. Muller, 1774) (Gastropoda:
Pulmonata: Helicidae)
The life
cycle of Helicodonta obvoluta, a Central European
species with its northern distribution border in Poland, was
studied in the field and in the laboratory. The spring reproductive
period from the beginning of April through May and June, the
autumn period lasts from mid-August till October. Eggs (13-27
per clutch) are laid in crevices in rotting wood; one to two
clutches are produced yearly, the maximum per lifetime being
six clutches. The eggs are laid in clusters, spherical or
slightly elongate (length/width ratio 1.0-.121), of major
diameter 2.1-2.85 mm, calcified. The incubation period is
14-21 days, hatching being asynchronous. The hatchlings consume
the remnants of the eggshell; egg cannibalism has been observed.
The final shell size (5.75-6.6 whorls, aperture surrounded
by lip) is reached in about 10 months, when the snails reach
sexual maturity. The mean shell increment is 0.4 whorls per
month. The maximum life span in the laboratory is 3 years,
and in the wild the average is 2 years.
**
TOMASZ K.
MALTZ.
Museum of Natural History, Wroc?aw University, Sienkiewicza
21, 50-335 Wroclaw, Poland.
email: via: bepok@biol.uni.wroc.pl
Seasonal
activity of the gonad of Helicodonta obvoluta (O.
F. Muller, 1774) (Gastropoda: Pulmonata: Helicidae)
Gonads
of adult Helicodonta obvoluta were histologically
examined (Bouin fixative, paraffin, haematoxylin and eosin)
at monthly intervals, from August 1998 till January 2000.
From January till December the number and size of oocytes
changed while spermatozoa were numerous throughout the year.
Two reproductive peaks (spring and autumn), observed both
in the field and in the laboratory, corresponded to the maturation
of oocytes. The number of oocytes increased in March, in April
large vitellogenic oocytes appeared, and their number reached
its maximum to decrease drastically at the end of June and
in July. The intensity of meiotic divisions increased from
the end of December till May, and from the end of August till
October. Both packets of fresh spermatozoa and new generations
of growing oocytes appeared in these periods
**
ANNA McIVOR
Pembroke College, Cambridge CB2 1RF, UK
email: alm1000@cam.ac.uk
Initial attempts
to rear British unionid mussels
Freshwater
mussels have a complicated life cycle, including a short parasitic
phase on a host fish. The recent decline of many species has
created interest in rearing some species artificially. In
this talk I will present my attempts to rear native British
unionids under laboratory conditions. So far 3 species have
been reared for a number of months. Anodonta spp.
reached lengths of over 1cm in 6 months. The techniques used
have been small-scale and use simple inexpensive apparatus.
I hope to eventually try these techniques on some of the more
endangered European species of freshwater mussels.
**
STEPHAN MULLER
Department of Zoology, University of Cambridge, Downing Street,
Cambridge CB2 3EJ, UK.
email: sjm50@cam.ac.uk
The Asian
Clam: where it has got to, what it is doing, and where it might
go next
During
the last five years, the invasive Asian clam Corbicula
fluminea has spread rapidly through one of Britains
most important wetland areas, the Norfolk Broads National
Park. Using C. fluminea as its main example, this
talk will illustrate some of the complex issues surrounding
the invasion of aquatic ecosystems by alien species. Over
the last two years, research has been carried out into the
origin, spread, autecology and impacts of this prolific freshwater
pest. In particular, I will present studies of the potential
impact of the clam on native bivalves, wildfowl and river
sediment composition.
**
LOUISE PLOWS
(with: R. T. COOK, A. J. DAVIES, A. J. WALKER)
School of Life Sciences, Kingston University, Penrhyn Road, Kingston-Upon-Thames,
Surrey, KT1 2EE. UK
email: k982236@kingston.ac.uk
Intracellular
signalling in hemocytes from the freshwater gastropod, Lymnaea
stagnalis.
Freshwater
snails are intermediate hosts for a range of helminth parasites
including important species of Schistosoma and Fasciola.
To understand how the snail responds to parasite infection,
the molluscan immune system needs to be explored. Hemocytes,
the major immune cells of snails, functionally resemble mammalian
macrophages and are responsible for the phagocytosis of invading
organisms, such as parasites. In macrophages, it is known
that activation of the highly conserved Mitogen-Activated
Protein Kinase (MAPK) pathway by infection results in actin
re-modelling, altered gene expression and phagocytosis. However,
the molecular mechanisms leading to phagocytosis in molluscan
hemocytes have not yet been elucidated. We have identified
two MAPK homologues (ERK 1/2) in hemocytes from the freshwater
snail L. stagnalis. As a model to study the molecular
mechanisms of phagocytosis in L. stagnalis hemocytes,
we have challenged these cells with lipopolysaccharide (LPS)
from E. coli, which resulted in activation of the ERK 1/2
pathway.
**
SIMON POLLARD
Canterbury Christ Church University College. C/O: 148 Mongeham
Road, Gt. Mongeham,
Nr. Deal, Kent CT14 9LL, UK
email: swp1@cant.ac.uk
Further
reflections on rugosity and egg laying by Biomphalaria
glabrata
Rugosity is
a noun based on the adjective rugose, meaning wrinkled. In an
ecological context, this is related to the structure of landscape/substratum.
Scale is of paramount importance to both an organism and substratum
under study, thus affecting all further considerations. In a freshwater
environment rugosity can and must be related to other ecological
aspects such as, the Reynolds number, and energy use, the Froude
number and Mannings n.
These aspects
are of great importance to aquatic organisms which are affected
by hydraulic phenomena. For aquatic snails, this is especially
important, as they are often found upon aquatic plants which support
the food supply of the snails as well as offering offer a place
of relatively safety for egg deposition .Several different rugosities
are being tested in the laboratory, to see whether snails have
a preference for any particular type of surface.
**
DINARZARDE
RAHEEM
c/o Department of Zoology, The Natural History Museum, London
SW7 5BD, UK.
email: c/o: fren@nhm.ac.uk
Land snail
diversity in Sri Lanka
Sri Lanka
has a rich land-snail fauna, which has been neglected since pioneering
work done during the British Colonial Period. a key objective
of a recently completed three year Darwin Initiative Project on
Sri Lankan land-snail diversity has been to develop a basic understanding
of the distribution and conservation status of the snail fauna.
Surveys of Sri Lankas three major climatic zones, the so-called
dry, wet and intermediate zones were carried out. Preliminary
findings show that the wet zone harbours a substantial share of
the islands land-snail diversity and endemism, with many
wet zone species having highly localised distributions. Our data
also strongly support the view that there are two distinct land-snail
communities in the lowland and montane regions of the wet zone.
**
PETER SÓLYMOS1
(with: Zoltán FEHÉR2 & Zoltán ER?SS3)
1 Department of Zoology, University of Debrecen, 4010 Debrecen,
P.O.B. 3, Hungary, email:solymos@tigris.klte.hu
2 Hungarian Natural History Museum, 1088 Budapest, Baross u. 13.,
e-mail: feher@zoo.zoo.nhmus.hu
3 1151 Budapest, Bem u. 36., Hungary, e-mail: erosspeter@hotmail.com
Geographic
variation of the land snail Granaria frumentum (Draparnaud,
1801) in central and southeast Europe.
Granaria
frumentum (Drap. 1801) is a widely distributed and mostly
xerophilous land snail species. The status of the subspecies
illyrica was critically investigated by us. We used
15-30 specimen samples of the species collected at each locality
from various sites of South and Central Europe. We measured
and counted several morphological variables and characters
on the shells, like height of shell, width of shell, height
of aperture, width of aperture, height of the ultimate and
the penultimate whorl, presence/absence of apertural folds,
marginal flange and cervical thickening at the aperture of
the shells. We performed statistical analyses for evaluating
our data. Our results show the separation of the Central European,
the Dinaric and the Central Balkanian forms on the basis of
the measured morphological variables. The pattern is different
concerning the shell characters, the subspecies illyrica is
confined to a narrow zone along the Adriatic Sea.
**
GEORGE SPELLER
Museum of Zoology, Cambridge University, Downing Street, Cambridge,CB2
3EJ, UK.
email:grs25@cam.ac.uk
Holocene molluscan
successions from Ireland: palaeoecological and biogeographical
significance
In Britain,
land snail analysis of Holocene (last 10,000 years) deposits has
revealed detailed successions often tied to secure radiocarbon-dated
chronologies. These have provided information on community development
and local environmental change, including episodes of prehistoric
human activity, from the end of the last glacial period. In comparison,
records of Holocene land snail successions from Ireland are sparse.
Consequently there is little understanding of Irish historical
biogeography. This project aims to increase the number and knowledge
of well-dated Holocene molluscan successions from Ireland. Two
recently discovered extensive tufa sites in west Ireland offer
the potential of obtaining detailed fossil mollusc records with
a high temporal resolution. Profiles from various locations across
both tufas have been sampled. The deposits are extremely rich
in land snails and contain numerous horizons with abundant charcoal
and burnt stones. This allows the exciting possibility of directly
linking snail faunas with known episodes of human activity.
**
SAMUEL STANTON
University of Portsmouth, Institute of Marine Sciences, Ferry
Road, Eastney, Hants, UK
email: sam.stanton@port.ac.uk
Electron microscope
analysis of bivalve larvae cilia structure from velar and mantle
regions
Analysis
of veliger anatomy is important in understanding their adaptation
to the planktonic environment. Scanning and Transmission Electron
Microscopy has been used to examine the cilature of the mantle
and velum of both Crassostrea gigas and Ostrea
edulis. Differences were observed in the cilia patterning
of the velum between the two, with O.edulis featuring
an additional row of compound cilia beneath the pre-oral compound
cilia. Both of these species have a distinct arrangement of
cilia on the inner fold of the mantle, with three types of
groupings of cilia identified. The histology and cytology
of the mantle and velum cells is under investigation. Differences
could relate to differences in early life history: O.edulis
is a short-term brooder, while C. gigas is a broadcast
spawner.
**
SID STAUBACH
Abt. Ökologie & Evolution, J.W. Goethe-Universität,
BioCampus Siesmayerstrasse,
60054 Frankfurt, Germany.
email: SIDSTAUBACH@SURFEU. de
Genetic
and morphological diversification of the nominal species Ancylus
fluviatilis on a European scale
Freshwater
limpets of the nominal species Ancylus fluviatilis
(O:F: MÜLLER, 1774) are found across the western Palaeartic
and North Africa. Data on mitochondrial(16S rDNA an COI) and
nuclear (ITS1) gene regions revealed that Ancylus fluviatilis
is composed of at least four highly divergent lineages. Three
clades are widespread, while the fourth is known from only
a single population. The aim of our study is to correlate
genetic informations with shell morphology and different ecological
parameters. Therefore, we collected over 50 populations over
the species range. Individuals were related with RFLP analysis
to one of the three main lineages. Morphological analyses
of the shells were performed with Fourier analysis. Correlation
analyses between different ecological parameters like temperatures,
precipitation and altitude and the lineage distributions were
carried out.
**
1BARBARA Tóth
(with: 1Péter Sólymos, and 2Jen? Pelbárt)
1 Department of Zoology, University of Debrecen, 4010 Debrecen,
P.O.B. 3, Hungary, e-mail: solymos@tigris.klte.hu
2 2094 Nagykovácsi, Semmelweis u. 10., Hungary, tel./fax:
+36-26-389-731, e-mail: pelbartj@axelero.hu
email: tb0008@stud.unideb.hu
Variation
in spire index and aperture deflection in Hungarian Helicid land
snails, and its functional significance
The aperture
deflection is a common feature in Helicid land snails. This called
the attention of various authors to explain its functional significance.
These are (1) the adaptation to reduce water loss from resting
individuals, since tangential aperture makes close seal against
surface, which benefit can explains the deflection in growth of
mature snails. (2) Adaptation to lower centre of gravity to reduce
the probability of dislodgement during inactivity. Because of
the great weight of the shell and enclosed visceral mass, the
shell balance is certainly a particular problem for terrestrial
snails. Our results show that there is a negative interspecific
correlation between spire index and the angle of aperture deflection
relative to the coiling axis. This result underlines both hypotheses
mentioned above. The analysis of the intraspecific variation is
in progress.
**
CATH WALLER
Scarborough Centre for Coastal Studies, University of Hull. C/o:
6, Woodview, Bogthorn, Oakworth, Keighley, BD22 7LP, UK. email:
Cathwaller@blueyonder.co.uk
An Investigation
of the Ecology of intertidal Nudibranchs at Robin Hoods Bay, N.Yorkshire
This ongoing
research represents the final independent research project of
my undergraduate studies. It aims to investigate the population
dynamics and species diversity of the intertidal nudibranchs of
a specific boulder field in the North-East of England and compare
the findings with research conducted at the same site between
1975-1976 in order to ascertain any similarities or differences
in species present and population dynamics/ numbers. Sampling
is conducted one hour either side of low water at spring tides.
Boulders are examined and any specimens of nudibranchs collected
for later identification in the lab. In addition to this any other
organisms present are also noted, as is the presence or absence
of egg masses. Once identified the specimens are returned to the
field. Finally it is hoped that it may be possible to grow nudibranchs
in the lab from egg masses found in situ, in order to study the
larval development. (Any advice in this area would be greatly
appreciated.)
**
HARRIET WOOD1
(with SANKURIE PYE2)
1National Museum and Galleries of Wales, Cathays Park, Cardiff
CF10 3NP, Wales.
2National Museum of Scotland, Chambers Street, Edinburgh EH1 1JF,
Scotland.
email: harriet.wood@ nmgw.ac.uk
Trailing Snails
Finding the Gems
Amongst
the most important parts of collections are the type specimens
they hold. Types are essential to taxonomists as they are
specimens used to fix scientific names, using Latin as a universal
language. Over the years the rules that regulate the naming
of animals have become stricter, but it is important to understand,
when interpreting historical material, that this was not the
case in previous times. For example, holotypes were not always
designated but a series of shells, known as syntypes were
used. This is not an accepted procedure today, a holotype
must be designated. Type material in historical collections
is not necessarily obvious from its labelling, or it can appear
to be obvious but is misleading. Often there can be confusion
when old terms such as Cotype are used and it
may need days of research to assess whether a specimen really
is a type, or not. This poster shows a case study
of a specimen of Melania tsushimana Fulton, 1914
labelled Cotype, from the National Museum of Scotland,
and how we researched the validity of its type status.