Cephalopod predation On a Desmoinesian brachiopod from the Naco Formation, central Arizona
Abstract
The beta member (Brew, 1970) of the Naco Formation at Kohl Ranch, central Arizona, has yielded an extensive invertebrate fauna and has been a collecting site for amateurs and paleontology classes for many years. Brew and Beus (1976) documented a diverse fauna of brachiopods, bivalves, gastropods, crinoids, and a conularid and dated it as Middle Pennsylvanian (Desmoinesian) in age. In addition, Webster (1981) has described the crinoids, and undescribed bryozoans, nautiloids, edrioasteroids, and sharks have been collected from the locality. Despite the unusual diversity and abundance of the invertebrates at this locality, there is almost no evidence of predation. Many of the biconvex brachiopods show unrepaired crushing similar to that reported by Alexander (1981) in a similar brachiopod fauna from the Upper Mississippian (Chesterian) Chainman Shale of west-central Utah. This damage was attributed to predation by durophagous sharks by Alexander; however, work by Elliott and Bounds (1987) suggests that in the Naco Formation, at least, this damage was more likely to have been caused by lithification of the surrounding sediments. However, one brachiopod from the Kohl Ranch locality does show repaired damage to both valves that was clearly caused by the unsuccessful attack of a predator. This specimen has been deposited at the Museum of Northern Arizona (MNA N8036).
- Publication:
-
Journal of Paleontology
- Pub Date:
- January 1988
- DOI:
- 10.1017/S0022336000059011
- Bibcode:
- 1988JPal...62..145E