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another highly interesting structural sequence characteristic. Hemocyanin sequences from Chitonida
appear to have a derived deletion of 5 amino acids, whereas Lepidopleurida appear to be “normal” or
plesiomorphic in more closely resembling gastropod hemocyanins. We predict that this might cause a
structural rearrangement of the complete hemocyanin molecule, and we further postulate that
hemocyanins of members of Lepidopleurida might also be able to form didecameric hemocyanins
which have never been observed within chitons yet. Further analyses are in progress to test this
prediction.
Hemocyanin: a 'respiratory' chance for molluscan phylogenetics
Lieb, Bernhard; Streit, Klaus
Institute of Zoology, University of Mainz, Müllerweg 6, 55099 Mainz, Germany,
Email: lieb@uni.mainz.de; kstreit@uni.mainz.de
Hemocyanins are ancient respiratory proteins exclusively found in molluscs and are a synapomorphy
of this phylum. Most probably, they had already evolved within the last common ancestor of all
molluscs before the latest Precambrian (544+ MYBP). We obtained hemocyanin sequence data from
>70 species of gastropods, cephalopods, protobranch bivalves, and chitons in order to trace the
phylogenetic relationships across and also within these groups at different taxonomic levels. At
higher taxonomic levels these data suggest a close relationship among protobranch bivalves and most
phylogenetic inferences also support the monophyletic origin of the four groups analysed. However,
very little was resolved for the relationships among these classes. In contrast, our analyses with
collaborators at lower phylogenetic levels show that hemocyanin is a good character to trace the
phylogeny within orders, families, or genera. We were able to use hemocyanin for (i) the
phylogeographic analyses of the Haliotidae and (ii) a preliminary analysis of Turbinidae phylogeny;
(iii) a broadened analyses on the cephalopod genus Spirula; (iv) substantial progress in resolving the
high-level phylogeny of Polyplacophora;, and (v) a combined analysis of a hemocyanin intron with
three other gene regions for inferring the phylogeny of a selected chiton genus, Lepidozona.
Significant results, limitations, and opportunities to trace molluscan phylogeny will be highlighted
and discussed.
Evolutionary patterns of the terrestrial mollusc genus Everettia and Meghimatium in the
Northern Borneo
Liew, Thor-Seng 1 ; Schilthuizen, Menno 2
1. Institute for Tropical Biology and Conservation, Universiti Malaysia Sabah, Loacked Bag 2073,
88999 Kota Kinabalu, Sabah, Malaysia,
Email: thorseng_liew@yahoo.com
2. National Museum of Natural History ‘Naturalis’, Leiden, The Netherlands,
Email: schilthuizen@yahoo.com
Sabah (Northern Borneo) had experienced the period of the Borneo's most active (and recent)
tectonic evolution. Expansion of land from Middle Eocene (ca. 40 mya) to Middle Pliocene (ca. 4
mya) and climate fluctuation in Pleistocene (2.5 mya to 10 kya). The interplay of the past geology
and climate is an agent for generating extra-ordinary diversity and genetic distinctiveness among
population of a species. However, to date, it is not clear to what extent these past processes are
reflected on contemporary distribution land snail in Borneo. The Mitochondrial DNA sequences from
16S rRNA and COI genes, and nuclear ribosomal DNA sequences from ITS-1 were used to
investigate phylogeographic patterns of the land snail Everettia (Gastropoda: Ariophatidae) and slug
Meghimatium (Gastropoda: Philomycidae) in the Northern Borneo. Furthermore, the genetic data
were also used for revision of taxonomy for both groups. Maximum parsimony and maximum
likelihood on these genetic datasets produced trees in general agreement for both genus in
plogeographical pattern and their taxonomy (based on the morphology) were also well-supported by
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