Creature Feature 22

Greetings, fans! Sorry about the lack of posts lately, I have been busy with work in the lab. This week, we're going to take a look at some of the turtles from Hell Creek, namely, the family Baenidae!

Plesiobaena antiqua, one of the species of Baenid turtle from Hell Creek. Work in progress.

Baenidae is an extinct clade of bottom-dwelling riverine turtles that were endemic to North America (Gaffney, 1972). They were an extremely diverse group during the late cretaceous, with between 14 and 17 species recognized from the Campanian through the Maastrichtian (Lyson and Joyce, in press). Interestingly, several species of Baenid turtle from Hell Creek actually survived into the Paleocene, making it by when many species perished (Lyson and Joyce, 2009).

Originally, some of the now-recognized species of Baenid turtle from Hell Creek were assigned to the genus Plesiobaena, but a redescription of several relevant specimens revealed that they were actually separate species (Lyson and Joyce, 2009). These include Peckemys brinkman, and Cedrobaena putorius (formerly Plesiobaena putorius). Other species of Baenid turtle from Hell Creek include Eubaena cephalica, Gamerabaena sonsalia, Palatobaena cohen, Stygiochelys estesi, and Neurankylus eximius (Lyson and Joyce, 2009).

Most baenids appeared to have preferred stream channel habitats, with the possible exception of Neurankylus eximius, which may have preferred floodplains as opposed to active channel margins (Hutchison and Archibald, 1986; Brinkman, 2005). It is likely that the high diversity of Baenid turtles was possible due to specializations in diet/habitat preference, and there is evidence for this based on the cranial morphology of several coexisting Baenid species. For example, the diet of Cedrobaena putorius and Palatobaena cohen likely consisted largely of molluscs and other hard-shelled crustaceans, whereas Peckemys brinkman and Eubaena cephalica appear to have been more generalist (Lyson and Joyce, 2009).

Well, I hope this has given you a bit more info on one of the families of turtles from Hell Creek! Note that the above picture is only representative of a single species, and additional models/textures will be made to represent the different taxa.

Acknowledgements:
Gaffney, E. S. 1972. The systematics of the North American family Baenidae (Reptilia, Cryptodira). Bulletin of the American Museum of Natural History 147: 241–320.
Lyson, T. R.; Joyce, W. G. In Press. A new baenid turtle from the Upper Cretaceous (Maastrichtian) Hell Creek Formation of North Dakota and a preliminary taxonomic review of Cretaceous Baenidae. Journal of Vertebrate Paleontology.
Lyson, T. R.; Joyce, W. G. 2009. A Revision of Plesiobaena (Testudines: Baenidae) and an Assessment of Baenid Ecology Across the K/T Boundary. Journal of Paleontology 83 (6): 833-853.
Hutchison, J. H.; Archibald, J. D. 1986. Diversity of turtles across the Cretaceous/Tertiary Boundary in northeastern Montana. Palaeogeography, Palaeoclimatology, Palaeoecology 55:1–22.
Brinkman, D. B. 2005. Turtles: Diversity, paleoeology, and distribution,. 202–220. In P. J. Currie, E. B. Koppelhus (eds.). Dinosaur Provincial Park: A spectacular ancient ecosystem revealed. Indiana University Press, Bloomingdale.