TERRESTRIAL REPTILE TRACKS AND MARINE REPTILE BODY FOSSILS FROM THE LOWER MUSCHELKALK (MIDDLE TRIASSIC) OF WINTERSWIJK, THE NETHERLANDS SANDER, Martin, KLEIN, Nicole, Univ. of Bonn, Bonn, Germany
The Winterswijk quarry (Lower Muschelkalk, lower Anisian) in the eastern Netherlands is probably the most interesting Muschelkalk outcrop today, as far as vertebrate fossils are concerned. The quarry exposes a 40 m thick section of mud-cracked laminated carbonate mudstones interpreted as tidal flat deposits similar to the Recent sabkhas of the Persian Gulf. In addition to the extremely common and well preserved tracks and trackways of terrestrial reptiles (mainly Rhynchosauroides and Procolophonichnium) covering countless bedding planes, the Winterswijk quarry is yielding an ever increasing amount of partially articulated or complete skeletons of marine reptiles such pachypleurosaurs (Anarosaurus and ?Dactylosaurus), nothosaurs (Nothosaurus), and the enigmatic Saurosphargis. These fossils are of particular interest because of their early geological occurrence and because they provide abundant material of otherwise only poorly known taxa. Studying morphology and alpha taxonomy of pachypleurosaurs and nothosaurs from Winterswijk will result in new and important insights into the phylogeny and evolution of the Sauropterygia. Ecological questions can be answered by focussing on the different ontogenetic stages and by using bone histology to collect life history data. The highly unusual taphonomy of the Winterswijk quarry, i.e. the combination of footprints of terrestrial reptiles (but no skeletal material) and marine body fossils (but no tracks), may be explained by wind tides bringing in carcasses of marine reptiles and stranding live animals, which then were scavenged upon after the tide went out by terrestrial reptiles that had specialized on this resource.
Saurosphargis volzi von Huene, 1936
classification: Sauropterygia, Saurosphargidae
size: ~60 cm in length [based on description and measurements by von Huene, 1936, and comparisons to other forms including Sinosaurosphargis yunguiensis]
holotype: Breslaw Museum [now lost, Pinna, 1999] paleontologist Wilhelm Volz found and briefly described the holotype of Saurosphargis
material: fragmentary partial postcranial skeleton that included a section of 12 incomplete back vertebrae with ribs.. (note: same as ?Paraplacodus)
locality: Gogolin, Upper Silisa, Silesian Province, Poland.
horizon: Chorzower Schichten, Lower Muschelkalk.
age: Anisian, middle Triassic ~246 Ma
paleoecology: marine
Note: Saurosphargis volzi (Huene 1936, Middle Triassic), was described from disassociated parts that were destroyed in bombing raids during WWII.
referred material: Institute of Geological Sciences, University of Worclaw, MGU Wr. 3873s: isolated vertebra. (note: Saurosphagis might not be a placodont, Rieppel, 1995)
locality: Gogolin, Upper Silisa, Silesian Province, Poland.
horizon: Gogolin-Layers, Lowermost Muschelkalk.
age: Anisian, middle Triassic ~246 Ma
paleoecology: marine
referred material: [currently being prepared) Placodus sp.
locality: Gelderland, Netherlands (52.0Â N, 6.7Â E: paleocoordinates 16.6Â N, 16.4Â E) Winterswijkse Steen-en Kalkgroeve, Netherlands
horizon: Lower Muschelkalk / Lower Wellenkalk layer 9 Member (Vossenveld Formation)
paleoecology: peritidal, marine
General Note: This diapsid reptile with a secondarily closed upper temporal fossa is convergent on cyamodontoid placodonts in having developed a dorsal body armor composed of small osteoderms. The underlying ribs are transversely broadened so as to establish contact along their length, thus forming a closed dorsal 'rib basket,' a unique morphology found in Saurosphargis volzi and Sinosaurosphargis yunguiensis
references:
Chun Li; Olivier Rieppel; Xiao-Chun Wu; Li-Jun Zhao; Li-Ting Wang (2011) A new Triassic marine reptile from southwestern China. Journal of Vertebrate Paleontology 31(2): 303-312
Friedrich von Huene (1936). "Henodus chelyops, ein neuer Placodontier". Palaeontographica. A84: 99â148.
Rieppel, O., 1995, The status of Anarosaurus multidentatus von Huene (Reptilia, Sauropterygia), from the Lower Anisian of the Lechtaler Alps (Arlberg, Austria): Palaontologische Zeitschrift, v. 69, n. Â, p. 289-299.
Rieppel, O., 1995, Fragmenta Sauropterygia : NeÃes Jahrbuch fur Geologie und Palaontologie, Abhandlungen, v. 197, n. 3, p. 383-397.
Rieppel, O., 1995. The genus Placodus: systematics, morphology, paleobiogeography and paleobiology. Fieldiana (Geology), N. S. 31: 1-44.
On October 7, 2020 at 8:03 AM Gregory Paul <gsp1954@aol.com> wrote:
I am looking for data to get a total length estimate for Saurosphargis voles.
GSPaul