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Updated: Oct 9, 2025
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Ablation of a Single Cell From Eight-cell Embryos of the Amphipod Crustacean Parhyale hawaiensis
Published on: March 16, 2014
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PHYLOGENETIC RELATIONSHIPS AMONG EXTANT BRACHIOPODS
1Department of Geology, University of California, Davis, California 95616-8605, USA.
Cladistics : the International Journal of the Willi Hennig Society
|December 18, 2021
Summary
This study supports the monophyletic status of Brachiopoda, particularly through soft anatomy characters. Inarticulate brachiopod monophyly requires further investigation, with potential shared primitive traits with articulates.
Area of Science:
- * Systematic Zoology
- * Phylogenetics
- * Evolutionary Biology
Background:
- * The monophyletic status and internal phylogenetic relationships of Brachiopoda have been debated.
- * Conflicting results from morphological and molecular studies complicate understanding brachiopod relationships with other lophophorate taxa.
Purpose of the Study:
- * To test current hypotheses of brachiopod relationships using a comprehensive phylogenetic analysis.
- * To clarify the monophyletic status of Brachiopoda and its major clades (Articulata and Inarticulata).
- * To identify potential biases in previous phylogenetic hypotheses.
Main Methods:
- * Phylogenetic analysis using PAUP 3.1.1.
- * Inclusion of 112 morphological and embryological characters from extant brachiopod superfamilies.
- * Utilized bryozoans, phoronids, pterobranchs, and sipunculids as outgroups.
Main Results:
- * Brachiopod monophyly is robustly supported, especially by soft anatomy characters.
- * Articulate brachiopod monophyly is strongly supported, while inarticulate monophyly shows weak support.
- * Calcareous inarticulates exhibit derived traits with other inarticulates and primitive traits with articulates.
Conclusions:
- * Brachiopod monophyly is well-supported, irrespective of shell origin debates.
- * Explicit detailing of uncertainties in Inarticulata status facilitates future research.
- * Further molecular studies are recommended to test these phylogenetic conclusions and lophophorate monophyly.
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