World Congress of Malacology Antwerp ... - Unitas Malacologica

described species of this genus, one of them, K. borealis Odhner, 1921, is previously known from
Norway. The new species differs from K. borealis in several characters including the position of the
dorsoterminal sense organ, the anatomy of the pericardioducts and spawning ducts, the configuration
of the copulatory stylets and the morphology of the scaly sclerites alongside the pedal fold.
Furthermore, neither the anatomical, nor the bathymetrical and geographical data of the new species
is consistent with the data of any of the other six species.
The continuous new findings of undescribed species of aplacophoran molluscs from all parts of the
world indicate that the biodiversity of these groups is vastly underestimated.
Mudwhelks in mangroves: the evolutionary history of the Potamididae
Reid, David G. 1 ; Williams, Suzanne 1 ; Lozouet, Pierre 2 ; Glaubrecht, Matthias 3
1. Natural History Museum, London SW7 5BD, UK,
Email: d.reid@nhm.ac.uk; s.williams@nhm.ac.uk
2. Muséum national d’Histoire Naturelle, 55 Rue de Buffon, 75005 Paris, France,
Email: lozouet@mnhn.fr
3. Museum für Naturkunde der Humboldt-Universität zu Berlin, Invalidenstr. 43, D-10115 Berlin,
Germany,
Email: Matthias.glaubrecht@museum.hu-berlin.de
Mudwhelks of the family Potamididae are among the most characteristic of the gastropods associated
with mangrove environments. In the Recent fauna they are represented by seven genera and a total of
about 30 species, of which 70% are restricted to the Indo-West Pacific province. In their distribution
and diversity gradient the Potamididae closely parallel the mangroves themselves, and they may
serve as a model for the diversification of the biota of the mangrove ecosystem. Based on sampling of
65% of the extant morphospecies and all genera, we present a molecular phylogeny of the
Potamididae. The group has an extensive fossil record throughout the Tertiary and the earliest fossils
of modern genera occur in the Eocene of the Tethys Sea. This, together with the phylogeny, suggests
a rapid radiation in the mangrove habitat following the appearance of mangrove trees. Closure of the
Tethyan Seaway in the early Miocene, and regional extinction of formerly widespread genera,
resulted in the modern restriction of most potamidid genera to either the Indo-West Pacific (IWP), or
to the Atlantic plus Eastern Pacific (AEP). However, molecular evidence has revealed one clade with
representatives in both the IWP and AEP. The genus Potamides has been considered to have had a
continuous fossil record in the Tethyan province since the Oligocene, with a single relict (P. conicus)
surviving in the Mediterranean and western Indian Ocean. Molecular evidence is inconsistent with
this view.
Data on the ecology and phylogeny of Atlantic Ovulidae (Mollusca: Gastropoda)
Reijnen, Bastian T.; Gittenberger, E.
National Museum of Natural History Naturalis, P.O. Box 9517, NL 2300 RA Leiden, The
Netherlands,
Email: reijnen@naturalis.nnm.nl; gittenberger@naturals.nnm.nl
During a fieldwork period from April till June 2005, 105 samples (~200 specimens) belonging to four
species of Ovulidae were collected along the leeward coast of Curaçao, The Netherlands Antilles.
Identification of most ovulid species is relatively difficult because clear taxonomical shell characters
are often lacking and the mantle can have many different patterns and a plethora of colour variations.
Most of this variation is probably related to the symbiotic or predatory relationship between the snails
and their soft coral hosts, resulting in camouflage of the snail on its host species or functioning as a
defence against predators, i.e. as a 'warning' for noxious properties.
To obtain a better insight in the life histories and phylogenetic relationships within this gastropod
family, ecological data (e.g. depth, host, position on host) were recorded and phylogeny
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