World Congress of Malacology Antwerp ... - Unitas Malacologica

teams in Japan and Russia within the last eight years. Time is too short to begin with a checklist or
with separate publication of the new species, so it is necessary to include them in my books. There
are to be two separate but overlapping taxonomic manual/revisions, the first to treat the species from
British Columbia south to central Baja California, the second to treat the north Pacific species from
British Columbia and Alaska, west to Kamchatka, the Kurile Islands, and Hokkaido, considering that
the north Pacific represents a continuous faunal region connected by the Bering Sea and the Aleutian
Islands. The northwestern Pacific species can now be integrated with the northeastern Pacific species,
thanks to the publication in 2006 of Kantor & Sysoev’s Illustrated Catalog of Russian gastropods.
With the help of a part-time imaging assistant over the last five years, the working illustrations of
about 400 half-page plates (for placement next to the text) for the southern book have been
completed; work on the illustrations for the northern book is well underway. Publication of the first
volume that treats 1400 species should be possible in two years.
The Holsteinian: MIS 7, 9 or 11?
Meijer, Tom
Naturalis, Dept of Paleontology, P.O. Box 9517, 2300 RA Leiden, The Netherlands,
Email: meijert@naturalis.nl
The Holsteinian is a Middle Pleistocene interglacial that has been introduced on the basis of marine
mollusc bearing deposits in Northern Germany. In Europe, the interglacial shows (except for marine
taxa) a remarkable molluscan record. Although individual species also occur in other interglacials,
the fluvial assemblages include Theodoxus danubialis, Viviparus diluvianus, Valvata naticina,
Parafossarulus crassitesta, Pisidium clessini, etc. Notably, many of these taxa are also present in the
preceding Fourth Cromerian Interglacial. The terrestrial 'Lyrodiscus assemblage' is considered to be
of Holsteinian age (is, however, absent in the Holsteinian type area) and includes Lyrodiscus
elephantium, Zonitoides sepultus, Aegopinella bourdieri, Aegopis acieformis, Ruthenica filograna,
Laminifera pauli, etc. All mentioned taxa (fluvial and terrestrial) occur far beyond their modern area
or are extinct.
The age of the Holsteinian was controversial and attributed to MIS (Marine Isotope Stage) 7, 9 or 11
respectively. Now, most authors consider the Holsteinian to represent MIS 11. However, the
problems in dating the Holsteinian stratotype show that this conclusion is premature and probably
incorrect.
Recently, Amino Acid Racemization dating of marine molluscs showed that the Holsteinian
stratotype dates from MIS 9. The Fourth Cromerian Interglacial at its type site appears to date from
MIS 11, and this was similarly shown for the Dutch 'Holsteinian' site of Neede. Therefore, at least the
characteristic fluvial assemblages with Viviparus diluvianus are NOT Holsteinian but date from the
preceding interglacial (but still MIS 11). These conclusions are corroborated by new insights in the
lithostratigraphy of the areas in question as well as absolute dating of the Holsteinian parastratotype.
These results have no bearing for the 'Lyrodiscus Assemblage' although many other data point to MIS
11, implying an age of Fourth Cromerian Interglacial as well. Similarly, any site attributed on sound
data to MIS 11, is not Holsteinian but Fourth Cromerian Interglacial.
Marine cryptic diversity: the allopatric component
Meyer, Christopher P.
Berkeley Natural History Museums, UC Berkeley, Berkeley, CA 95720, USA,
Email: cpmeyer@berkeley.edu
Molecular data are revolutionizing our ability to characterize global biodiversity. One of the most
outstanding marine patterns emerging from molecular systematics and phylogeography is that most
sister taxa do not share geographic ranges, and that overlap often requires millions of years. As such,
allopatric speciation is supported as the dominant mode driving marine diversification.
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