Northeastern Section - 40th Annual Meeting (March 14–16, 2005)

Paper No. 2
Presentation Time: 8:00 AM-12:00 PM

REPORT OF A LATE EARLY DEVONIAN HOMOSTEID ARTHRODIRE IN THE MID HUDSON VALLEY OF NEW YORK


CHIARELLO, Robert E.1, WAINES, Russell H.2 and SEKSINSKY, Justine2, (1)Department of Geology, SUNY New Paltz, PO Box 401, New Paltz, NY 12561, (2)Geological Sciences, State Univ of New York (SUNY) at New Paltz, New York, 75 South Manheim Blvd, New Paltz, NY 12561, chiare99@newpaltz.edu

More than half of a median dorsal of a homosteid arthrodire placoderm has been found in the calcareous mudstone of the Aquatuck member of the Schoharie formation in the Town of Ulster, New York. The size of the bone indicates a relatively large animal estimated at 1.5 to 2 meters in length. Apparent puncture marks in the bone may indicate the predation or scavenging of the animal by another large animal, possibly an arthrodire of similar size. Apparent degradation at the lateral lower edge of the dermal plate may indicate the decomposition of the bone within the matrix sediment prior to lithification.

The presence of numerous sediment filled worm burrows and fragmentary fossils may indicate a marine depositional environment below the photic zone.

This is the first apparent record of a homosteid arthrodire in the United States and the second in North America.