Data/hora: 10/06/2024 12:26:44

Provedor de dados: 	104	
País: 	Brazil	
Título: 	Polychaeta, Annelida, and Articulata are not monophyletic: articulating the Metameria (Metazoa, Coelomata)	
Autores: 	Almeida,Waltécio de Oliveira; Christoffersen,Martin Lindsey; Amorim,Dalton de Souza; Garraffoni,André Rinaldo Senna; Silva,Gustavo Sene.	
Data: 	2003-03-01	
Ano: 	2003	
Palavras-chave: 	Bilateria; Clitellata; Ecdysozoa; Enterocoela; Metazoa; Phylogeny; Polychaeta.	
Resumo: 	Polychaetes are metameric worms recognized for having parapodia, chaetae, and nuchal organs. Some authors have extended the Annelida to include Pogonophora, Echiura, and Clitellata. These suggestions are insufficient to generate a monophyletic group. They do not take into account two very large and important clades that in a cladistic analysis at a higher level are shown to be nested within the Annelida: the Ecdysozoa (arthropods and related taxa) and Enterocoela (deuterostomes and related taxa). Evolutionary histories of most characters across metazoan phyla are still very poorly known. Metameres and coeloms have been considered homoplastic in the literature, and yet the homeobox genes responsible for the expression of metamerism and of paired appendages, at least, are very largely distributed among the Metazoa. A phylogenetic analysis was performed for the ingroups of Polychaeta, including Clitellata, Enterocoela, and Ecdysozoa as terminal taxa. The remaining non-metameric phyla Platyhelminthes, Nemertea, Mollusca, and Sipuncula were included to root the tree within the Bilateria. Empirical data was obtained from the literature and run with the software Hennig86 with two comparative interpretations of a priori hypotheses of primary homology: one with negative characters (coding losses) and another considering only positive characters (without assumptions about losses). The most relevant conclusions are: (1) Annelida and Polychaeta are non-monophyletic, even when including Echiura, Clitellata, and Pogonophora; (2) Articulata, as traditionally circumscribed for Annelida and Arthropoda, is also not monophyletic; (3) Metameria becomes monophyletic only when Ecdysozoa and Enterocoela are included in addition to the traditional annelid taxa; (4) Ecdysozoa are the sister group of Aphrodita; (5) Clitellata are related to deposit-feeding sedentary polychaetes (scolecids), and Questidae represent their sister group; (6) Owenia plus Enterocoela form a monophyletic group related to the tubicolous polychaetes.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-81752003000100006	
Editor: 	Sociedade Brasileira de Zoologia	
Relação: 	10.1590/S0101-81752003000100006	
Formato: 	text/html	
Fonte: 	Revista Brasileira de Zoologia  v.20 n.1 2003	
Fonte: 	info:eu-repo/semantics/openAccess