| one publication added to basket [17315] | Nemertodermatida, a basal bilaterian group
Jondelius, U.; Ruiz-Trillo, I.; Baguñà, J.; Riutort, M. (2001). Nemertodermatida, a basal bilaterian group. Belg. J. Zool. 131(Suppl. 1): 59
In: Belgian Journal of Zoology. Koninklijke Belgische Vereniging voor Dierkunde = Société royale zoologique de Belgique: Gent. ISSN 0777-6276; e-ISSN 2295-0451, more
Also appears in:Saló, E.; Watson, N.; Schockaert, E. (Ed.) (2001). Proceedings of the 9 th International Symposium on the Biology of the Turbellaria, Barcelona, Spain, June 2000. Belgian Journal of Zoology, 131(Suppl. 1). Koninklijke Belgische Vereniging voor Dierkunde = Société royale zoologique de Belgique: Diepenbeek. 236 pp., more
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Document type: Summary
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| Authors | | Top |
- Jondelius, U.
- Ruiz-Trillo, I.
- Baguñà, J.
- Riutort, M.
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| Abstract |
The taxon Nemertodermatida was originally classified within the Acoela, but was later separated from the acoels on account of their distinct intestinal lumen. More recently Nemertodermatida was hypothesised as the sister group of the Acoela in the taxon Acoelomorpha owing to similarities in epidermal ciliary systems in the two groups. However, in the first analyses of ribosomal DNA the nemertodermatid Nemertinoides elongatus grouped with members of the Rhabditophora and not with acoels. We sequenced 18S rDNA from four Nemertodermatida and used parsimony analysis and parsimony jack-knifing of nucleotide and nucleotide triplet sequences to generate a hypothesis of the phylogeny of the Nemertodermatida. A secondary structure aligmnent and five multiple aligmnents with different gap opening penalties (ClustalW) were evaluated, all yielding similar results. The Nemertodermatida group basally in the bilaterian clade separate from the Acoela in our most parsimonious trees. The same results were obtained when the data set was analysed with maximum likelihood methods. Branch support is low for the basal clades of the Bilateria in 18S rDNA. When Acoela were excluded from the data set, there was jack-knife support for the Nemertodermatida as the basal bilaterian clade. When the Nemertodermatida were excluded and Acoela left in the dataset, the Acoela was supported as the sister group of other bilaterians. With both Acoela and Nemertodermatida present, support for a basal bilaterian clade was absent. The sequence labelled Nemertinoides elongatus (Genbank Acc no U70083) grouped with Rhabditophora (separately from the Nemertodermatida ) also in our analyses. This indicates that the sequence is derived not from a member of the Nemertodermatida, but from a species of the Rhabditophora. |
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