Paleozoic record of morphologica diversity in blastozoan echinoderms.

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چکیده

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The phylogenetic relationships between major groups of plesiomorphic pentaradial echinoderms, the Paleozoic crinoids, blastozoans, and edrioasteroids, are poorly understood because of a lack of widely recognized homologies. Here, we present newly recognized oral region homologies, based on the Universal Elemental Homology model for skeletal plates, in a wide range of fossil taxa. The oral regio...

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ژورنال

عنوان ژورنال: Proceedings of the National Academy of Sciences

سال: 1992

ISSN: 0027-8424,1091-6490

DOI: 10.1073/pnas.89.16.7325