Access

Letters to Nature

Nature 410, 81-84 (1 March 2001) | doi:10.1038/35065078; Received 22 August 2000; Accepted 8 November 2000

Open Innovation Challenges

  • Optimizing Sub-cellular Localization Tags

    • Deadline: Nov 29 2009
    • Reward: $20,000 USD

    The Seeker is looking for methods to optimize sub-cellular localization tags for protein expression....

  • Single-cell Analysis Platform

    • Deadline: Dec 02 2009
    • Reward: $5,000 USD

    This Challenge is looking for novel approaches to analyzing changes at a single-cell level. This is...

naturejobs

A primitive sarcopterygian fish with an eyestalk

Min Zhu1, Xiaobo Yu2 & Per E. Ahlberg3

  1. Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, PO Box 643, Beijing 100044, China
  2. Department of Biological Sciences, Kean University, Union, New Jersey 07083, USA
  3. Department of Palaeontology, The Natural History Museum, Cromwell Road, London SW7 5BD, UK

Correspondence to: Per E. Ahlberg3 Correspondence and requests for materials should be addressed to M.Z.

Top

The discovery of two Early Devonian osteichthyan (bony fish) fossils1, 2, 3, 4 has challenged established ideas about the origin of osteichthyans and their divergence into actinopterygians (teleosts and their relatives) and sarcopterygians (tetrapods, coelacanths, lungfishes and related groups)5, 6, 7. Psarolepis from China1, 2, 8, 9 and an unnamed braincase from Australia3 combine derived sarcopterygian and actinopterygian characters with primitive features previously restricted to non-osteichthyans, suggesting that early osteichthyan evolution may have involved substantial parallellism between sarcopterygians and actinopterygians. But interpretation of these fossils has been hampered by poor phylogenetic resolution1, 3. Here we describe a basal sarcopterygian fish, Achoania gen, et sp. nov., that fills the morphological gap between Psarolepis and higher sarcoptergyians. We also report the presence of eyestalk attachments in both Achoania and Psarolepis, showing that this supposedly non-osteichthyan feature occurs in basal sarcopterygians as well as the actinoptergyian-like Australian braincase3.