cf. Archelon ischyros Wieland, 1896

Remarks

• Right humerus

• Collector:    Anonymous

• Formation:  Found in float (probably from Marlbrook Marl)

• Location:     Northeast Texas

• Based on discussions with vertebrate paleontologists, the two pieces of the humerus appear to be from two different individuals.

• One colleague suggested that the two pieces may indeed be from the same individual, but that the two weathered out of the formation at different times (i.e., one piece has been sitting exposed in the river bottom longer than the other piece and so is in worse shape).

Remarks

• Left hyoplastron

• Collectors:    Lisa and Kelly Irwin

• Collection:    Arkansas Game and Fish Commission

• Formation:   Taylor Group, Marlbrook Marl

• Location:      Hempstead County, Arkansas

General Info

Synonyms (older names and misidentifications in the literature)

• 1896 Archelon ischyros Wieland

• 1903 Archelon ischyros Wieland; Wieland

• 1909 Archelon ischyros Wieland; Wieland

• 1993 Archelon ischyros Wieland; Derstler, Leitch, Larson, Finsley & Hill

• 1997 Archelon ischyros Wieland; Hirayama

Stratigraphic Occurrence

• Taylor Group, Marlbrook Marl of Texas

• Taylor Group, Marlbrook Marl of Arkansas

• Montana Group, Top of the Pierre Formation of South Dakota

Age

• Archelon ischyros Wieland is a latest Campanian age turtle (~72 mya).

Geographic Occurrence (by no means an all-inclusive list)

• Fall River County, SD

• Hempstead County, AR

• Shannon County, SD

• Texas (county ?)

Remarks

         For identification and descriptions, see:

• Hirayama, R.  1997.  "Distribution and Diversity of Cretaceous Chelonioids".  In:  Callaway, J. M.; Nicholls, E. L., ed's.  Ancient Marine Reptiles.  Part 3, Testudines.  New York:  Academic Press, Chapter 8, pp. 225–241, fig's 5 and 8 (great side-by-side comparison of the post cranial material of the different cheloniids).

• Wieland, G. R.  1896.  Archelon ischyros:  A New Gigantic Cryptodire Testudinate from the Fort Pierre Cretaceous of South Dakota.  American Journal of Science, Fourth Series 2 (12), 399–412, plate 6 (great figures!).