Saccorhytus is an early ecdysozoan and not the earliest deuterostome - Nature.com

Analyses of newly discovered specimens of the early Cambrian microscopic animal Saccorhytus coronarius support its taxonomic classification in total-group Ecdysozoa.

Peterson, K. J. & Eernisse, D. J. The phylogeny, evolutionary developmental biology, and paleobiology of the Deuterostomia: 25 years of new techniques, new discoveries, and new ideas. Org. Di… [+8024 chars]

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