World Congress of Malacology Antwerp ... - Unitas Malacologica

Atopos. Although very poorly surveyed there are nearly as many species now known from New
Guinea and surrounding islands as from all of North America north of Mexico, an area 43 times
larger. Estimates suggest that continued surveys could double the known fauna of New Guinea.
Endemic molluscs (Gastropoda, Bivalvia) in hypogean habitats in Slovenia
Slapnik, Rajko
Institute of Biology, The Scientific Research Centre of the Slovenian Academy of Sciences and Arts,
Novi trg 2, SI-1001 Ljubljana, Slovenia,
Email: RajkoSl@zrc-sazu.si
Slovenia is situated in Central Europe and covers an area of 20,273 km 2 (that's half the size of
Switzerland). Four major European geographic regions meet in Slovenia: the Alps, the Dinaric area,
the Pannonian plain and the Mediterranean. There is 26,000 kilometres of rivers and streams, some
7,500 springs of drinking water. Forests cover half the territory. Most of Slovenia has a continental
climate with cold winters and warm summers. The average rainfall is 1000 mm for the coast, up to
3500 mm for the Alps. Approximately 8 % of the Slovenia's territory is specially protected.
Molluscs are a relatively well studied group as their investigation goes back to the previous century.
This applies particularly to land and freshwater snails. Molluscs are a group that is extremely
interesting because of Slovenia's geographic location and the diversity of ecosystems. They are
affected by central European, Alpine, Dinaric, Pannonian, and Mediterranean regions. Roughly 30
species and subspecies of stygobionts (genera: Belgrandiella, Boleana, Erythropomatiana, Hadziella,
Hauffenia, Horatia, Iglica, Kerkia, Mervicia, Neohoratia, Bythiospeum (Paladilhiopsis), Sadleriana,
Lanzaiopsis, Bythinella, Acroloxus, Congeria) and 9 species and subspecies of troglobionts (genera:
Zospeum, Spelaeodiscus) are recognized as endemic in Slovenia. Until now, molluscs have been
protected completely only in their subterranean habitats as a constituent part of hypogean animal
world. Hypogean waters are endangered, along with molluscs inhibiting them, by increasing
pollution. In the future, more attention will have to be paid to areas inhabited by endemic species.
These are the mountain and karst areas.
An integrative approach identifies developmental sequence heterochronies in freshwater
basommatophoran snails
Smirthwaite, Jennifer J. 1 ; Rundle, Simon D. 1 ; Bininda-Emonds, Olaf R.P. 3 ; Spicer, John I. 1
1. Marine Biology and Ecology Research Centre, University of Plymouth, Drakes Circus, Plymouth
PL4 8AA, UK,
Email: Jennifer.smirthwaite@plymouth.ac.uk; srundle@plymouth.ac.uk; jispicer@plymouth.ac.uk
3. Institut für Spezielle Zoologie und Evolutionsbiologie mit Phyletischem Museum, Friedrich-
Schiller-Universität Jena, Erbertstrasse 1, 07743 Jena, Germany,
Email: olaf.bininda@uni-jena.de
Adopting an integrative approach to the study of sequence heterochrony, we compared the timing of
developmental events encompassing a mixture of developmental stages (e.g. trochophore, veliger,
hippo) and functional traits (e.g. eye spots, heart beat, crawling) in the embryos of twelve species of
basommatophoran snails, within an explicit phylogenetic framework. There was clear evidence for
altered timing of developmental events between species and PARSIMOV analysis formally
demonstrated functional heterochronies associated both with basal branches within the phylogeny
and with terminal speciation events. On average, 0.50 and 0.58 events were inferred to have changed
their position in the developmental sequence on internal and terminal branches, respectively; these
values are comparable with frequencies of sequence heterochrony reported in mammals. Directional
heterochronies such as the early occurrence of body flexing in relation to the ontogeny of the eye
spots, heart beat and free swimming events occurred convergently and/or at different levels (i.e.
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