World Congress of Malacology Antwerp ... - Unitas Malacologica

handling for the entire procedure are given and critically evaluated. 3D processing is carried out with
amira® software. The number of section images utilized for one specimen ranges from 120 to 400.
Resolution should be adjusted to result in a file size for an image stack of approximately 400 MB.
For completion and corrections of “materials” selected by hand drawing, “interpolate” turned out to
be a most functional tool. The major steps in graphical processing from section image capturing until
3D visualization are illustrated.
Examples of 3D visualization of micromolluscs are followed by a discussion on the application
possibilities of the method as a whole. At last, ways for directly embedding and displaying 3D
specimens in standard desktop publishing and presentation software are demonstrated.
Genital system anatomy and development of Ovatella myosotis (Gastropoda, Ellobiidae) by 3D
computer visualization
Ruthensteiner, Bernhard 1 ; Stocker, Bettina 2
1. Zoologische Staatssammlung München, Münchhausenstraße 21, 81247 Munich, Germany,
Email: BRuthensteiner@zsm.mwn.de
2. Institut für Neurobiologie, FU Berlin, Königin-Luise-Straße 28-30, 14195 Berlin, Germany,
Email: bettina.stocker@web.de
The hermaphroditic genital system of the Euthyneura is highly complex and thus useful for
systematic and phylogenetic analyses. Because primitive taxa with general plesiomorphic conditions
in morphology and development are particularly informative, a member of the “archaeopulmonate”
family Ellobiidae, Ovatella myosotis is investigated. Adult anatomy as well as organogenesis of the
genital system is analyzed in detail by means of serial sectioning and 3D computer reconstruction and
visualization. In the adult a spermoviduct leads from the middle portion, which has four nidamental
glandular portions, to a common genital aperture. From here two separate structures, the vas deferens
and a groove on the body surface, run anteriorly. The latter is termed egg groove because it carries
the egg ribbon anteriorly, a function that is recognized here for the first time in the Ellobiidae. The
evolution of this structure is discussed. In development, the organ system arises from four separate
anlagen: (1) the ovotestis anlage, (2) the pallial anlage giving rise to hermaphrodite duct, fertilization
pouch-spermatheca complex, nidamental glandular complex and spermoviduct, (3) the bursa
copulatrix anlage, and (4) the anlage of the copulatory organ, vas deferens and egg groove. This
development mode very much resembles that of the siphonariid pulmonate Williamia radiata,
supporting its interpretation as a plesiomorphy in Pulmonata. Similarities in development of primitive
pulmonates and evolution in gastropods lead to the assumption that ontogenesis of this organ system
reflects evolution to some degree.
Cytogenetic damage in gill cells of blue mussels from different areas of the Baltic Sea
Rybakovas, Aleksandras; Baršienė, Janina
Institute of Ecology of Vilnius University, Akademijos 2, 08412 Vilnius, Lithuania,
Email: arybakovas@ekoi.lt; janbar@ekoi.lt
The frequency of micronuclei (MN) and other nuclear abnormalities (nuclear buds (NB), bi-nucleated
(BN) and fragmented-apoptotic (FA) cells) were studied in bivalve molluscs (Mytilus spp.) as
biomarkers of environmental pollution impact in different areas of the Baltic Sea. Mussels were
collected from three sites of the Lithuanian coast, four sites of the Gulf of Gdansk (Poland) and one
reference site – Kvädöfjärden (Sweden) in April-June 2001-2003 and October - November 2001 and
2002. MN frequency in gill cells of mussels from the Lithuanian coast ranged from 1.2 (Palanga,
June 2001) to 3.85 MN/1000 cells (Būtingė, September 2002). After the oil spill in the Būtingė oil
terminal (November 2001), the Palanga and Būtingė sites were impacted by oil. In June 2002 and
2003, MN incidences were significantly increased (p=0.0030) in resident mussels. MN frequencies in
molluscs from different stations of the Gulf of Gdansk were not significantly different. The highest
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