16 Topics in Vertebrate Paleontology

Thursday, 2 May 2013
1:30 PM - 5:30 PM
Room 2040

A REVIEW OF THE CHONDRICHTHYANS FROM THE MISSISSIPPIAN SYSTEM OF NORTHERN ALABAMA, USA

Paper number: 16-2
Program: Theme Sessions
Time: 1:35 PM – 1:55 PM

Authors

Abstract

It has been over a century and a half since Tuomey’s (1858) seminal work on the geology and paleontology of Alabama, wherein he provided the first descriptions of Mississippian chondrichthyans in the state. Since that time very little has been published on the subject, which is surprising given the extensive Mississippian age exposures found throughout northern Alabama. Casual observation of the limestone benches in and around north-central Alabama has revealed diverse and abundant chondrichthyan faunas, and vertebrate fossil occurrences appear to be well known to local collectors.

Recent fieldwork and examination of several museum and private collections has revealed that the number of chondrichthyan species occurring in upper Mississippian (primarily Chesterian) rocks of northern Alabama is greater than previously known. Combined with taxa documented prior to the present report, 26 distinct chondrichthyan taxa are found in calcareous strata within the Monteagle Limestone, Pride Mountain Formation, Bangor Limestone, Hartselle Sandstone, and Tuscumbia Limestone.

We emend several earlier taxonomic identifications, with Cladodus newmani herein reassigned to C. sp. cf. C. bellifer, and C. magnificus is Saivodus striatus. Newly documented species include Polyrhizodus sp., cf. Ctenoptychius apicalis, Deltodus sp. cf. D. undulatus, and Deltoptychius sp. cf. D. acutus. In addition, occurrences of Carcharopsis wortheni are corroborated.

Additionally, a cursory inspection of micro-remains from the Pride Mountain Formation have revealed the presence of Cooleyella and Isacrodus. We have no doubt that additional species will be uncovered, especially when rock exposures are more carefully inspected for macro- and micro-vertebrate remains.