Annulonemertes (phylum Nemertea): when segments do not count.
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ABSTRACT:
SUBMITTER: Sundberg P
PROVIDER: S-EPMC1975765 | biostudies-literature | 2007 Oct
REPOSITORIES: biostudies-literature
Publications
Annulonemertes (phylum Nemertea): when segments do not count.
Biology letters 20071001 5
We estimated the phylogenetic position of the pseudosegmented ribbon worm Annulonemertes minusculus to test proposed evolutionary hypotheses to explain these body constrictions. The analysis is based on 18S rDNA sequences and shows that the species belongs to an apomorphic clade of hoplonemertean species. The segmentation has no phylogenetic bearing as previously discussed, but is a derived character probably coupled to the species' interstitial habitat. ...[more]
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