An Early Late Cretaceous Nodosaur from the Marine Eagle Ford Group of North Central Texas, a Test of the Endothermy in the Mosasaurs from the Late Cretaceous of Angola, and the Ontogeny of a New Pipid Frog from the Miocene of Ethiopia
The first two chapters of this dissertation detail the study of the newly recovered Holland Farm nodosaur (SMU 77100) from the Eagle Ford Group (95.29 ± 0.04 MA) of Mansfield in north central Texas. The objectives of this research are (1) to describe the anatomy of the Holland Farm nodosaur, (2) to determine its phylogenetic position within Ankylosauria, (3) to elaborate the substantial differences in body size and osteoderm morphology in armored dinosaurs occurring in north central Texas during the short duration of the Late Albian and Early Cenomanian, and (4) to provide a radiometric date for the lowermost member of the Eagle Ford Group in Dallas County.
The third chapter of this work tests the potential for large bodied Cretaceous marine diapsids to maintain elevated body temperatures, as suggested by a number of recent studies. This analysis focuses on comparing the body temperature of two mosasaurines, Globidens phosphaticus and Prognathodon kianda, with that of poikilotherms from the Bench 19 fauna of Bentiaba, Angola. This locality is temporally well constrained, and allows for the comparison of body temperature among sympatric taxa, which has not been feasible in previous studies of this nature. Evidence of elevated body temperatures will greatly enhance our understanding of the paleobiology of one of the dominant groups of Late Cretaceous marine predators.
The fourth chapter of this dissertation is a continuation of my master’s research describing the anatomy, ontogeny, and paleoecology of a new pipid frog from the Miocene of Ethiopia. In addition to naming a new genus of xenopodine pipid, this chapter advocates for the recognition of Silurana as a genus distinct from Xenopus. The new pipid named here provides morphological support and a chronologic framework to existing molecular studies in support of Silurana
Louis L. Jacobs
Michael J. Polcyn
Neil J. Tabor
Dale A. Winkler
John G. Wise
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Clemens, Matt, "An Early Late Cretaceous Nodosaur from the Marine Eagle Ford Group of North Central Texas, a Test of the Endothermy in the Mosasaurs from the Late Cretaceous of Angola, and the Ontogeny of a New Pipid Frog from the Miocene of Ethiopia" (2018). Earth Sciences Theses and Dissertations. 9.