Paleontological Journal

, Volume 48, Issue 1, pp 74–78 | Cite as

New data on the exoskeleton of the osteostracan genus Aestiaspis (Agnatha) from the Silurian of Saaremaa Island (Estonia) and the Severnaya Zemlya Archipelago (Russia)

  • O. B. AfanassievaEmail author
  • T. Märss


The histological structure of exoskeleton of the osteostracan genus Aestiaspis Janvier et Lelievre, 1994 from the Silurian of Saaremaa Island is examined for the first time. The preservation of the material enables the fine exoskeleton structure to be described in detail. The study of Aestiaspis from Saaremaa Island and the Severnaya Zemlya Archipelago has shown structural details of exoskeleton sculpture. The formation of consolidated cephalothoracic shield in the phylogeny of Tremataspidoidei is discussed. The taxonomic position of the genus Aestiaspis in the Osteostraci system is analyzed.


Agnatha osteostracans Aestiaspis morphology Silurian Saaremaa Island Estonia Severnaya Zemlya Archipelago Russia 


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© Pleiades Publishing, Ltd. 2014

Authors and Affiliations

  1. 1.Borissiak Paleontological InstituteRussian Academy of SciencesMoscowRussia
  2. 2.Institute of GeologyTallinn University of TechnologyTallinnEstonia

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