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 The annual Forum of the Malacological Society of London, in the Natural History Museum in London on 7th November, attracted an enthusiastic group of young researchers from the U.K. and abroad Abstracts
In Alphabetical Order Anatomical and molecular character evolution in the Basommatophora:
conflict or congruence? Christian
Albrecht1 , Thomas Wilke2, Kerstin Kuhn1and
Bruno Streit1 1Department of Ecology and Evolution, 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 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 from the 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. Specimen collection and preparation techniques
for electron microscopy Alex Ball Electron Microscope Unit, The Natural History Museum, Cromwell Road, London SW7 9BD, UK Email:
a.ball@nhm.ac.uk Ideally specimens for electron microscopy (EM) should be fixed whilst still alive, the specimens should then be processed as rapidly as possible. It is 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 agents 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 preweighed 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 mininise 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. The
role of taxonomy in distributional mapping- one example of an overlooked
species. Ron CarR 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 authorities 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. Palaeoecological and sedimentological investigations
on the fauna and deposits of the Tata brickyard ISTV็N CZICZER1, S็NDOR GULY็S1 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 Batthyny u. 45 Email: cziczer@yahoo.com The prodelta, delta slope deposits of the Szk 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 czjzeki-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 czjzeki M. Hrnes, Congeria partschi CZJZEKI and in the coquinas of storm deposits Congeria ungulacaprae (Mnster)]. The second richest group is that of limnocardiids which will possibly yield a lot of new endemic species 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. Fossil
cold seeps in the Caribbean FIONA GILL 12, Ashdell Road, Broomhill, Sheffield SIO 3DA, UK. (Earth Sciences, University of Leeds) Email: fgill@earth.leeds.ac.uk 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 (3 Ma ago), the Caribbean Sea provided a direct, open
water link between the Atlantic and Pacific Oceans.
Conservation Genetics of Margaritifera
margaritifera (freshwater pearl mussel) in the British Isles ANNA HOLMES National Museum of Wales, Cathays Park, Cardiff CF10 3NP, UK. Email: Anna.Holmes@mngw.ac.uk 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 and 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 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? Restoration
of native oyster beds in Strangford Lough, Northern Ireland Richard
Kennedy with David Smyth and Dai Roberts School of Biology and Biochemistry, Queen's University, Belfast BT9 7BL. Email:
c/o: d.roberts@Queens-Belfast.ac.uk 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 ceased. Although growth trials of oyster spat in the Lough in the 1970's
produced favourable results for both 0. 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 cultch and seed, re-laying
native adults, estimating oyster and cultch densities and 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 1000m2).
In contrast, densities of 0. edulis on commercial mats
ranged between 66 and 100 individuals m2. 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: 1.
benthic
and intertidal surveys to ascertain the current state of 0. edulis
stocks. 2.
plankton
surveys August 2003 for comparison with 1998 data.
3.
investigation
into predatory impact on developing spat.
4.
comparison
of the biodiversity of established undisturbed beds and fished beds.
The
impact of fire on land snail communities in calcareous Provence. Laurence Kiss Institut Mditerranen d'Ecologie et de Palocologie, Equipe Ecologie du Paysage, Case 461, Facult des Sciences et Techniques de St Jrme, 13397 Marseille CEDEX 20, France. Email: laurence.kiss@univ.u-3mrs.fr 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 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. Life
cycle of Helicodonta obvoluta (0. F. Muller, 1774) (Pulmonata: Helicidae) Tomasz K. Maltz Museum of Natural History, Wrocaw University, Sienkiewicza 21, 50-335 Wrocaw, Poland. Email: bepok@biol.uni.wroc.pl 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 extends 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, and are spherical or slightly
elongate (length/width ratio 1.0-1.21), 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. Seasonal
activity of the gonad of Helicodonta obvoluta (0. F. Muller,
1774) (Pulmonata: Helicidae) Tomasz K. Maltz Museum of Natural History, Wrocaw University, Sienkiewicza 21, 50-335 Wrocaw, Poland. Email: bepok@biol.uni.wroc.pl 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. Initial
attempts to rear British unionid mussels Anna McIvor Pembroke College, Cambridge CB2 IPF, UK Email: alml000@cam.ac.uk 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. Anadonta
spp. reached lengths of over l cm 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. The
Asian Clam: where it has got to, what it is doing, and where it might
go next Stephan Muller Department of Zoology, University of Cambridge, Downing Street, Cambridge CB2 3EJ, UK. Email: sjm5O@cam.ac.uk During the last five years, the invasive
Asian clam Corbicula fluminea has spread rapidly through one
of Britain's 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. Intracellular
signalling in hemocytes from the freshwater gastropod, Lymnaea stagnalis Louise Plows with
R. T. Cook, A. J. Davies, and A. J. Walker School
of Life Sciences, Kingston University, Penrhyn Road, Kingston-Upon-Thames,
Surrey, KT1 2EE. UK 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. Further
reflections on rugosity and egg laying by Biomphalaria
glabrata Simon Pollard .. 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 Manningีs ิnี. 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 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. Land snail diversity in Sri Lanka Dinarzarde Raheem c/o Dept of Zoology, The Natural History Museum, London
SW7 5BD, UK. Email:
c/o: fren@nhm.ac.uk Geographic
variation of the land snail Granaria frumentum (Draparnaud, 1801) in central
and southeast Europe. Peter Solymos1
with Zoltn Fehr2 & Zoltn Eross3 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. Holocene
molluscan successions from Ireland: palaeoecological and biogeographical
significance George Speller Museum of Zoology, Cambridge University, Downing Street, Cambridge,CB2 3EJ, UK. Email:
grs25@cam.ac.uk 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. Electron
microscope analysis of bivalve larvae cilia structure from velar and
mantle regions Samuel Stanton University of Portsmouth, Institute of Marine Sciences,
Ferry Road, Eastney, Hants, UK 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 ciliature of the mantle and velum of both Crassostrea gigas and Ostrea edulis. Differences were observed in the cilia patterning of 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. Genetic
and morphological diversification of the nominal species Ancylus
fluviatilis on a European scale Sid Staubach Abt. Okologie & Evolution, J.W. Goethe-Universitat, BioCampus Siesmayerstrasse, 60054 Frankfurt, Germany. Email:
SIDSTAUBACH@SURFEU.de Variation
in spire index and aperture deflection in Hungarian helicid land snails,
and its functional significance.
Barbara
Tth1
with Pter Slymos1,
and Jen Pelbrt2 1Department of Zoology, University of Debrecen, 4010 Debrecen,
P.O.B. 3, Hungary, 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) an adaptation to reduce water loss from resting individuals, since
tangential aperture makes a close seal against the surface, which benefit
can explain the deflection in growth of mature snails; (2) an adaptation
to lower the centre of gravity to reduce the probability of dislodgement
during inactivity. Because of the great weight of the shell
and enclosed visceral mass, 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. An
Investigation of the Ecology of intertidal 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 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.) Trailing
Snails - Finding the Gems ... Harriet
Wood1 with Sankurie Pye2 1National Museum and Galleries of Wales, Cathays Park, Cardiff CF 1 0 3NP, Wales. 2National Museum of Scotland, Chambers Street, Edinburgh
EH1 1JF, Scotland. Email: harriet.wood@
mngw.ac.uk 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 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. Top left: coffee interval in the seminar room. Top right: poster session in adjacent space. Lower left: Demonstrating a poster, Chung-Chi Hwang (with Hsuch-Wen Chang) on phylogenetic relationships of the Satsuma-like land snails (Pulmonata: Camaenidae) from Taiwan (pankalaking@hotmail.co). Lower right: Part of Fiona Gills poster on fossil cold seeps in the Caribbean. Illustrations
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