Lower Cambrian vendobionts from China and early diploblast evolution.

Early Life Institute and Key Laboratory of Continental Dynamics, Northwest University, Xi'an 710069, China.
Science (Impact Factor: 31.48). 06/2006; 312(5774):731-4. DOI: 10.1126/science.1124565
Source: PubMed

ABSTRACT Ediacaran assemblages immediately predate the Cambrian explosion of metazoans and should have played a crucial role in this radiation. Their wider relationships, however, have remained refractory and difficult to integrate with early metazoan phylogeny. Here, we describe a frondlike fossil, Stromatoveris (S. psygmoglena sp. nov.), from the Lower Cambrian Chengjiang Lagerstätte (Yunnan, China) that is strikingly similar to Ediacaran vendobionts. The exquisite preservation reveals closely spaced branches, probably ciliated, that appear to represent precursors of the diagnostic comb rows of ctenophores. Therefore, this finding has important implications for the early evolution of this phylum and related diploblasts, some of which independently evolved a frondose habit.


Available from: Zhifei Zhang, Jun 11, 2015
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