Sundberg Per, Strand Malin
Department of Zoology, Göteborg University, PO Box 463, 405 30 Göteborg, Sweden.
Biol Lett. 2007 Oct 22;3(5):570-3. doi: 10.1098/rsbl.2007.0306.
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.
我们估计了伪分节带虫微小环纽虫（Annulonemertes minusculus）的系统发育位置，以检验提出的进化假说来解释这些身体收缩现象。该分析基于18S核糖体DNA序列，结果表明该物种属于链纽虫目物种的一个特化分支。如前所述，这种分节在系统发育上并无关联，而是一个可能与该物种的间隙生境相关的衍生特征。
