A primitive fish close to the common ancestor of tetrapods and lungfish

ABSTRACT The relationship of the three living groups of sarcopterygians or lobe-finned fish (tetrapods, lungfish and coelacanths) has been a matter of debate1,2,3,4,5. Although opinions

still differ, most recent phylogenies suggest that tetrapods are more closely related to lungfish than to coelacanths6,7,8,9,10. However, no previously known fossil taxon exhibits a concrete

character combination approximating the condition expected in the last common ancestor of tetrapods and lungfish—and it is still poorly understood how early sarcopterygians diverged into

the tetrapod lineage (Tetrapodomorpha)7 and the lungfish lineage (Dipnomorpha)7. Here we describe a fossil sarcopterygian fish, _Styloichthys changae_ gen. et sp. nov., that possesses an

eyestalk and which exhibits the character combination expected in a stem group close to the last common ancestor of tetrapods and lungfish. _Styloichthys_ from the Lower Devonian of China

bridges the morphological gap between stem-group sarcopterygians (_Psarolepis_ and _Achoania_)10 and basal tetrapodomorphs/basal dipnomorphs. It provides information that will help in the

study of the relationship of early sarcopterygians, and which will also help to resolve the tetrapod–lungfish divergence into a documented sequence of character acquisition. Access through

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BEING VIEWED BY OTHERS A NEW EXCEPTIONALLY WELL-PRESERVED BASAL ACTINOPTERYGIAN FISH IN THE JUVENILE STAGE FROM THE UPPER TRIASSIC AMISAN FORMATION OF SOUTH KOREA Article Open access 03

January 2024 A NEW ELPISTOSTEGALIAN FROM THE LATE DEVONIAN OF THE CANADIAN ARCTIC Article Open access 20 July 2022 _PYGMACLYPEATUS DAZIENSIS_, A UNIQUE LOWER CAMBRIAN ARTHROPOD WITH TWO

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ACKNOWLEDGEMENTS We thank M. M. Chang and P. E. Ahlberg for advice and discussions, K. S. Thomson for comments and corrections, M. Yang for artwork, J. Zhang for photographic work, and X. Lu

for specimen preparation. This work was supported by the Special Funds for Major State Basic Research Projects of China, the Chinese Foundation of Natural Sciences, and the US National

Geographic Society. X.Y. thanks Kean University for faculty research and development support. AUTHOR INFORMATION AUTHORS AND AFFILIATIONS * Institute of Vertebrate Paleontology and

Paleoanthropology, Chinese Academy of Sciences, PO Box 643, 100044, Beijing, China Min Zhu * Department of Biological Sciences, Kean University, Union, New Jersey, 07083, USA Xiaobo Yu

Authors * Min Zhu View author publications You can also search for this author inPubMed Google Scholar * Xiaobo Yu View author publications You can also search for this author inPubMed 

Google Scholar CORRESPONDING AUTHOR Correspondence to Min Zhu. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare that they have no competing financial interests. SUPPLEMENTARY

INFORMATION SUPPLEMENTARY ANALYSIS, DATA AND FIGURES (PDF 563 KB) RIGHTS AND PERMISSIONS Reprints and permissions ABOUT THIS ARTICLE CITE THIS ARTICLE Zhu, M., Yu, X. A primitive fish close

to the common ancestor of tetrapods and lungfish. _Nature_ 418, 767–770 (2002). https://doi.org/10.1038/nature00871 Download citation * Received: 27 December 2001 * Accepted: 09 May 2002 *

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