World Congress of Malacology Antwerp ... - Unitas Malacologica

asal origin of species from Sulawesi, and a derivation of Australian taxa from the Southeast Asian
mainland. Low genetic differences among the species or populations render the assumption of an
intralacustrine radiation in ancient lake Inlé in Myanmar unlikely, while for Lake Poso on Sulawesi
the data at least suggest the occurrence of cryptic lacustrine species.
Crystallographic textures of shell layers in Patellogastropoda: a new tool unraveling their
phylogeny
Frýda, Jiří 1 ; Sasaki, Takenori 2
1. Czech Geological Survey, Klárov 3/131, 118 21 Praha 1, Czech Republic,
Email: bellerophon@seznam.cz
2. The University Museum, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033,
Email: sasaki@um.u-tokyo.ac.jp
Limpet shells belonging to the Patellogastropoda have the most diversified microstructural pattern
among all living gastropods and data on their mineralogy and microstructure have been frequently
used for their classification. In contract to microstructure (characterizing a shape of biocrystals) there
are almost no data on crystallographic textures of patellogastropod shells (characterizing an
arrangement of crystal axes of individual biocrystals). Shell layers having the same microstructure
can have different crystallographic textures and vice versa. Thus, analyses of crystallographic texture
and microstructure of patellogastropod shells provide non-redundant characters. To fill a gap in our
knowledge on the crystallographic textures of patellogastropod shells, we have applied several
diffraction techniques providing complementary information about the crystallographic texture and
mineralogy of their shells. We analyzed individual shell layers of 14 patellogastropod species
belonging to Lottiidae (Niveotectura, Patelloida, Lottia, and Nipponacmea), Patellidae (Scutellastra),
Nacellidae (Cellana), Lepetidae (Limalepeta), and Acmaeidae (Pectinodonta). Our analysis has
revealed a large variety of textural patterns of the patellogastropod shells. The crystallographic
texture pattern in corresponding shell layers of closely related taxa is identical but different in
distantly related taxa. This fact confirms that the crystallographic texture is under biological control
as shell microstructure and it is not driven only by abiological forces (like a mineral epitaxy). The
crystallographic texture pattern represents characters useful for a phylogenetic reconstruction of the
higher levels of the classification of the Patellogastropoda. In addition, our analysis suggests that
textural analysis together with mineralogical and microstructural data can help resolve problems of
homology of individual shell layers in the patellogastropod shells.
“Niku-nuki”, a useful method for preparation of shell-bearing molluscan specimens
Fukuda, Hiroshi 1 ; Haga, Takuma 2 ; Tatara, Yuki 3
1. Conservation of Aquatic Biodiversity, Faculty of Agriculture, Okayama University, Tsushimanaka
1-1-1, Okayama 700-8530, Japan,
Email: suikei1@cc.okayama-u.ac.jp
2. Department of Biological Science, Graduate School of Sciences, The University of Tokyo, 7-3-1
Hongo, Bunkyo-ku, Tokyo 113-0033, Japan,
Email: haga@kahaku.go.jp
3. Department of Biology, Faculty of Science, Toho University, Miyama 2-2-1, Funabashi 274-8510,
Japan,
Email: ykui@msc.biglobe.ne.jp
Often only one or a few individuals of rare species are collected. How do we treat them as intact
voucher specimens? The shell of the whole individual in formalin or alcohol will corrode or fade. In
order to dissect the soft parts, you must crack or dissolve the shell.
“Niku-nuki”, a traditional method used by Japanese malacologists overcomes this dilemma. It is
applicable to minute molluscs. The outline is:
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