Pseudemys is a genus of large, herbivorous, freshwater turtles of the eastern United States and adjacent northeast Mexico. They are often referred to as cooters, which stems from kuta, the word for turtle in the Bambara and Malinké languages, brought to America by enslaved people from Africa.[2]
Etymology
The generic name Pseudemys is derived from the Greek words, pseudes meaning false or misleading, and emydos a freshwater turtle, implying a resemblance to, but not included in the genus Emys.[3] The trivial names, or specific epithets, of five of the species are toponyms, named for places where the species were first discovered including, the Florida peninsular (P. peninsularis),[4] the Suwannee River (P. suwanniensis),[5]Alabama (P. alabamensis),[6]Florida (P. floridana),[5] and Texas (P. texana).[7] Two are patronyms, or eponyms, honoring prominent zoologists, George Robert Zug, curator of Amphibians and Reptiles at the Smithsonian, National Museum of Natural History (P. gorzugi),[8] and George Nelson, botanist, zoologist, and Chief Taxidermist at the Museum of Comparative Zoology, Harvard (P. nelsoni).[9] The other specific epithets are derived from Latin: P. concinna, from concinnus meaning neat, trim, or skillfully joined, likely in reference to the relatively smooth, stream-lined shell, or possibly the colors and patterns on the carapace;[5][10] and P. rubriventris, from rubidus reddish, and venter belly, referring the red color of the plastron.[11]
Taxonomy
The genus Pseudemys has an extensive, complicated, and at times contentious taxonomic history. Historically the genus has been intertwined with other genera, at times included in other genera or having members of other genera include in it (Chrysemys, Clemmys, Emys, Ptychemys, and Trachemys), as well as the recognition of a number of additional subspecies well into the third quarter of the 20th century.[5][12][13] As recently as 1984 one reviewer of the genus called the chrysemyd complex "a taxonomic morass".[14]: 3 p. Another wrote "Pseudemys has long been recognized as something of a taxonomic quagmire, and has been the subject of a confusing litany of taxonomic arrangements."[15]: 270 p. By the last decade of the 20th century, taxonomist were largely in agreement on a monophyletic genus and the recognition of nine taxa. However the relationships and status of some of the taxa in the genus, as species or subspecies, has been inconsistent.[16] Some have recognized all nine taxa as full species.[17] Two clades, or species groups, are recognized within the genus, the red-bellied cooters (P. alabamensis, P. nelsoni, P. rubriventris) comprising one group (subgenus Ptychemys) and the remaining six species comprising the other group (subgenus Pseudemys).[18]
A study published in 2012 examined nuclear and mitochondrial genes from geographically widespread samples of all nine taxa, but identified only three clades [species], with significant integration between some clades, and stated: "We found little or no evidence supporting the division of Pseudemys into its currently recognized species/subspecies. Rather, our data strongly suggest that the group has been oversplit and contains fewer species than currently recognized." Somewhat confoundedly, the study did not recommend any taxonomic changes, concluding the resolution of Pseudemys will necessitate further analysis with an integrated review of morphology, historical biogeographic data, and extensive geographic sampling with large amounts of molecular (DNA) data.[15]: 269 p.
Description
Members of this genus are among the largest of the Emydidae, capable of attaining carapace lengths of over 16.0 in (40.64 cm) and capable of weighing up to 35 lbs (15.876 kg), although most individuals are far smaller. All are aquatic, spending the majority of their time in lakes, rivers, and ponds where they can easily be seen basking on rocks and logs in sunny weather.
Diet: As juveniles, Pseudemys are typically omnivorous, feeding on variety of plants as well as sponges, bryozoans, snails, clams, crayfish, and insects such as caddisfly larvae, dobsonfly larvae, dragonfly nymphs, fly and mosquito larvae, aquatic beetles, caterpillars, crickets, and grasshoppers. Tadpoles and very small fish (e. g. darters, Percina) are also included in their diets. Both juveniles and adults will consume carrion on occasion.[20]
The diet shifts to a greater percentage of vegetation as the turtles mature. Adults P. peninsularis are reported to be 90% herbivorous, and adult P. nelsoni, P. rubriventris, and P. suwanniensis are almost exclusively herbivorous. Pseudemys concinna are known to retain a greater degree of animal prey in their diet than most species in the genus, but are still predominantly herbivorous as adults. In addition to a variety of algae and aquatic mosses, plants reported in the diets include fanwort (Cabomba), coontails (Ceratophyllum), duckweed (Lemna minor), large-flowered waterweed (Egeria densa), waterthyme (Hydrilla verticillata), water milfoil (Myriophyllum), fragrant water-lily (Nymphaea odorata), southern waternymph (Najas guadalupensis), spadderdock (Nuphar luteum), pondweed (Potamogeton), arrowhead (Sagittaria sp.), and water-celery (Vallisneria americana) among many others.[20]
Gallery
River cooter (Pseudemys concinna), photographed in situ, Marion County. Texas (13 April 2017)
Rio Grande cooter (Pseudemys gorzugi), a juvenile from Kinney County, Texas (11 Nov. 2018)
Florida Red-bellied Cooter (Pseudemys nelsoni), Monroe County, Florida (21 Dec. 2011)
Suwannee Cooter (Pseudemys suwanniensis), close up of head, Levy County, Florida (28 Apr. 2013)
Texas cooter (Pseudemys texana), photographed in situ, Kerr County, Texas (9 May 2014)
References
^Gray, John Edward 1855 [1856]. Catalogue of Shield Reptiles in the Collection of the British Museum. Part I. Testudinata (Tortoises). The Trustees (British Museum of natural History), London, 79 pp.
^"Cooters". Merriam-Webster. Archived from the original on 2011-07-14. Retrieved 2010-08-03.
^ abSeidel, Michael and Carl H. Ernst. 1996. Pseudemys. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 625: 1-7 pp.
^Seidel, Michael and Carl H. Ernst. 1998. Pseudemys peninsularis. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 669: 1-4 pp.
^ abcdeSeidel, Michael and Michael J. Dreslik. 1996. Pseudemys concinna. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 626: 1-12 pp.
^McCoy, Clarence. J. and Richard C. Vogt. 1985. Pseudemys alabamensis. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 371: 1-2 pp.
^Etchberger, Cory R. and John B. Iverson. 1990. Pseudemys texana. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 485: 1-2 pp.
^Ernst, Carl H. 1990. Pseudemys gorzugi. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 461: 1-2 pp.
^Beolens, Bo, Michael Watkins, and Michael Grayson (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. [pages 188 &294] ISBN1-4214-0135-5
^Smith, Hobart M. and Rozella B. Smith. 1979. Synopsis of the Herpetofauna of Mexico, Vol VI: Guide to Mexican Turtles, Bibliographic Addendum III. John Johnson. North Bennington, Vermont. 1044 pp. [page 444] ISBN0-910914-11-7
^Graham, Terry E. 1991. Pseudemys rubriventris. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 510: 1-4 pp.
^Seidel, Michael and Carl H. Ernst. 2012. Trachemys. Catalogue of American Amphibians and Reptile. Society for the Study of Amphibians and Reptiles. 891: 1-17 pp.
^ abWard, Joseph P. 1984. Relationships of Chrysemyd Turtles of North America (Testudines: Emydidae). Special Publications, The Museum Texas Tech University. No. 21. 50 pp.
^ abSpinks, Phillip Q., Robert C. Thomson, Gregory B. Pauly, Catherine E. Newmane, Genevieve Mount, and H. Bradley Shaffer. 2013. Misleading phylogenetic inferences based on single-exemplar sampling in the turtle genus Pseudemys. Molecular Phylogenetics and Evolution, 68 (2); 269-281.
^ abcPowell, Robert, Roger Conant, and Joseph T. Collins (2016). Peterson Field Guide to Reptiles and Amphibians of Eastern and Central North America, Fourth Edition. Boston and New York: Houghton Mifflin Harcourt. xiii + 494 pp. [pages 211-217] ISBN978-0-544-12997-9
^ abSeidel, Michael E. 1994. Morphometric Analysis and Taxonomy of Cooter and Red-Bellied Turtles in the North American Genus Pseudemys (Emydidae). Chelonian Conservation and Biology 1(2): 117-130.
^ abcErnst, Carl. H., and Jeffrey E. Lovich. 2009. Turtles of the United States and Canada. Baltimore, Maryland: Johns Hopkins University Press. xii + 827 pp. [pages 364-407] ISBN0-8018-9121-3
^ abcLe Conte, John E. 1830. Description of the species of North American tortoises. Annals of the Lyceum of Natural History of New York 3 [1829]: 91-131.
^Carr, Archie F. 1938. Pseudemys nelsoni, a new turtle from Florida. Occasional Papers of the Boston Society of Natural History 8: 305-310.
^Carr, Archie F. 1938. A new subspecies of Pseudemys floridana, with notes on the floridana complex. Copeia 1938 (3): 105-109.
^Jackson, Dale R. 1995. Systematics of the Pseudemys concinna-floridana complex (Testudines: Emydidae): an alternative interpretation. Chelonian Conserv. Biol. 1 (4): 329-333.
^Thomas, R. Brent., and Kevin P. Jansen. 2006. Pseudemys floridana – Florida cooter. Pages 338–347 in P. A. Meylan, editor. Biology and conservation of Florida turtles. Chelonian Research Monographs No. 3: 376.
^Matt J. Elliott, J. Whitfield Gibbons, Carlos D. Camp, and John B. Jensen. 2008. Amphibians and Reptiles of Georgia. University of Georgia Press. Athens. 600 pp. ISBN0820331112