Fossils & Strata No. 40: Erik Jarvik on Ichthyostega

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The new issue of Fossils & Strata is the long-awaited monograph by Erik
Jarvik on Ichthyostega. You can order it from Scandinavian University
Press, P.O. Box 2959, Toyen, Oslo, Norway (WWW home page at
http://193.69.40.2/; e-mail to subscription@scup.no).


Jarvik, E. 1996: The Devonian tetrapod Ichthyostega. Fossils and Strata 40.
213 pp. Oslo. ISSN 0300-9491. ISBN 82-00-37660-5. USD 49.00.

ABSTRACT: The material of Ichthyostega Säve-Söderbergh 1932 collected by
the Danish expeditions to East Greenland (1929-1955) led by Lauge Koch is
described and documented by photographs of all important specimens. The
ichthyostegids are related to the osteolepiforms, and comparisons with the
Devonian osteolepiform fish Eusthenopteron and post-Devonian
stegocephalians are made. In some respects the ichthyostegids are
fish-like, whereas in others they have reached the tetrapod level. However,
they also show specializations unparalleled in later tetrapods and belong
to a sidebranch of the Osteolepipoda. Several new structures, such as
canals for the occipital arteries, the prominent sacculus vesicle, the
parotic crest of the palatoqudrate, the attachment areas for a paired
basicranial muscle, and an arcual plate dorsal to the notochord are
described. Special problems, e.g., the terminology of the dermal bones of
the skull roof, cranial kinetism, resegmentation, the metapterygial stem,
and the origin of the tetrapod limbs, are discussed. It is concluded that
the hindlimb in Ichthyostega is pentadactyl and that pentadactyly is
primitive for the Osteolepipoda.


(For me this volume was a particularly pleasing editorial task, since
Jarvik's earlier reconstruction of Ichthyostega, as reproduced in my
high-school biology textbook, was one of the things that attracted me to
palaeontology in the first place.)

Stefan Bengtson
Editor, Fossils & Strata


Stefan Bengtson                      _/        _/ _/_/_/    _/        _/
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