Phylogeny and evolution of Monoplacophora and basal Mollusca reconstructed by morphological and molecular data sets

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New evidences from fossils, as well as microanatomical and molecular genetic results, have challenged textbook knowledge regarding the origin and relationships of major molluscan groups. The Monoplacophora (Tryblidia), which are famous as “living fossils”, could be the key to understanding the early molluscan evolution. However, they represent one of the last classes in the animal realm with minimum sequence data available, and thus are amongst the most wanted study objects by systematists. Extracted quality DNA and first sequences of three species (Micropilina sp., Neopilinidae sp., Laevipilina antarctica) are available to the applicant, and further species will be searched for. The here proposed project shall analyse monoplacophorans and other selected members of basal molluscan groups using 1) conservative standard sequence markers (complete 18S and 28S rDNA and Histone 3 gene), 2) mitochondrial genomics (especially gene arrangements), 3) a survey of hox genes, and 4) genes contributing to shell formation that will be explored as novel markers. Comparatively, structures of poorly known basal molluscs will be examined, and a very large set of morphological data will be established and analyzed phylogenetically. Exploring the hotly debated basal molluscan phylogeny will contribute to a better understanding of the origin and evolution of Mollusca, the molluscan shell, and other organs such as serially repeated structures.