- 著者
-
Tomioka Shinri
Kakui Keiichi
Kajihara Hiroshi
- 雑誌
- Zoological Science (ISSN:02890003)
- 巻号頁・発行日
- vol.35, no.5, pp.436-445, 2018-10
- 被引用文献数
-
4
Capitellids have emerged as monophyletic in most but not all recent molecular phylogenies, indicating
that more extensive taxon sampling is necessary. In addition, monophyly of most or all
capitellid genera was questionable, as some diagnostic characters vary ontogenetically within
individuals. We tested the monophyly of Capitellidae and eight capitellid genera using phylogenetic
analyses of combined 18S, 28S, H3, and COI gene sequences from 36 putative capitellid species.
In our trees, Capitellidae formed a monophyletic sister group to Echiura, and Capitella was
also monophyletic, separated by a long branch from other capitellids. Well-supported clades each
containing representatives of different genera, or containing a subset of species within a genus,
indicated that Barantolla, Heteromastus, and Notomastus are likely not monophyletic. We mapped
three morphological characters traditionally used to define capitellid genera (head width relative to
width of first segment, number of thoracic segments, and number of segments with capillary chaetae)
onto our tree. While Capitella showed unique character states, states in the other genera were
decidedly not phylogenetically informative. Morphology-based capitellid taxonomy will require a
fine-scale reevaluation of character states and detection of new characters.