Note to users. If you're seeing this message, it means that your browser cannot find this page's style/presentation instructions -- or possibly that you are using a browser that does not support current Web standards. Find out more about why this message is appearing, and what you can do to make your experience of our site the best it can be.

Science 25 May 1973:
Vol. 180. no. 4088, pp. 866 - 868
DOI: 10.1126/science.180.4088.866
Prev | Table of Contents | Next

Articles

Fordilla troyensis Barrande: The Oldest Known Pelecypod

John Pojeta Jr. 1, Bruce Runnegar 2, and Jiri Kriz 3

1 U.S. Geological Survey, Washington, D.C. 20242
2 University of New England, Armidale, New South Wales, Australia
3 Central Geological Survey, Prague, Czechoslovakia

Specimens of the small bivalved animal Fordilla troyensis Barrande from New York State show that this fossil is the oldest known pelecypod mollusk and not a conchostracan arthropod. This finding extends the range of the class Pelecypoda backward in time from the Early Ordovician (about 495 million years ago) to the Early Cambrian (about 540 to 570 million years ago). The morphology of Fordilla troyensis suggests that it lived infaunally and that it was ancestral to the pelecypod subclasses Heteroconchia and Isofilibranchia.


THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Diversification and biogeography of bivalves during the Ordovician Period.
J. C. W. Cope (2002)
Geological Society, London, Special Publications 194, 35-52
   Abstract »    PDF »
A new look at early bivalve phylogeny.
J. C. W. Cope (2000)
Geological Society, London, Special Publications 177, 81-95
   Abstract »    PDF »
Environmental and Evolutionary Stability in Bivalve Mollusks.
C. W. Thayer and C. W. Thayer (1974)
Science 186, 828-830
   Abstract »    PDF »
Molluscan Phylogeny: The Paleontological Viewpoint.
B. Runnegar, B. Runnegar, and J. Pojeta Jr. (1974)
Science 186, 311-317
   Abstract »    PDF »


To Advertise     Find Products

Science. ISSN 0036-8075 (print), 1095-9203 (online)