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Significance of sperm morphology and 18 and 28S rRNA gene nucleotide sequences of brachiopods for their systematics and phylogenyтезисы доклада
- Авторы: Drozdov A.L., Vinnikova V.V., Tyurin S.A., Vladychenskaya I.P., Petrov N.B.
- Сборник: Molecular Phylogenetics. Contr. 2nd Moscow intern. conf. "Molecular phylogenetics"(MolPhy-2)
- Тезисы
- Год издания: 2010
- Первая страница: 29
- Последняя страница: 29
- Аннотация: Comparative study of sperm structure in echinodermates, mollusks, and brachiopods revealed significant difference between inarticulate (Linguliformea и Craniaformea) and articulate (Rhynchonelliformea) brachiopods in gametes morphology. Sperm cells in species of inarticulate brachiopods were found to be similar to those in species of primitive brachiopods, bivalve mollusks, and some of polychaetes with outer fertilization, whereas in articulate brachiopods they are similar to sperm of echinodermate species. This could be considered as evidence for early branching-off lophophorates from the main bilaterian steam before its splitting into Protostomia and Deuterostomia, but such a conclusion conflicts with molecular data. In molecular phylogenetic trees, brachiopods together with phoronids comprise a good supported clade within Lophotrochozoa, placed inside Protostomia between mollusks and annelids. In this clade called Brachiozoa, phoronids comprise a basal group, and brachiopods split up into groups corresponding articulate (Rhynchonelliformea) and inarticulate (Linguliformea and Craniaformea) lineages. Thus, sperm similarity between brachiopods and echinodermates is rather homoplasy, whereas such a similarity between Linguliformea and Craniaformea should be considered as an evidence for the validity of Inarticulata as a taxon of supraclass range. New data on the sperm structure allow to suppose the name Lingulophyles with typical genus Lingula for inarticulates, and the name Coptothyrophyles with typical genus Coptothyris for articulates.
- Добавил в систему: Петров Николай Борисович