Dyoplax

Source: Wikipedia, the free encyclopedia.

Dyoplax
Temporal range: 228 
Ma
↓
 Late Triassic
Original lithographic illustration of the holotype of Dyoplax arenaceus, from Fraas, 1867
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Suchia
Family: †Erpetosuchidae
Genus: †Dyoplax
Fraas, 1867
Type species
†Dyoplax arenaceus
Fraas, 1867

Dyoplax is an extinct

natural cast of a nearly complete skeleton that lacked only parts of the tail and limb bones.[1]

Classification

Aetosauridae".[3] Several other papers published in later years have also placed the genus within Pseudosuchia.[4][5][6][7] In 1956 the genus was referred to Notochampsidae, now known as Protosuchidae.[8] It was suggested to be a possible erpetosuchid in 1966,[9][10] but was later classified as one of the earliest protosuchids in 1994.[11]

In that same year a paper was published that identified several

Aetosauria.[12] This confirmed that Dyoplax was not within the order
Aetosauria as had been previously speculated because it lacked four out of five of the synapomorphies associated with Aetosauria.

A paper published in 1998 by Spencer et al. considered Dyoplax to be within

squamosal. On this basis, the authors concluded that there was enough evidence to place Dyoplax within Sphenosuchia. The age of the specimen within the strata would make Dyoplax the oldest sphenosuchian known at the time, predating other genera from the late Carnian that were once thought to be the oldest members of Sphenosuchia such as Hesperosuchus and Parrishia.[15] However, Maisch, Matzke and Rathgeber (2013) questioned the placement of Dyoplax within Crocodylomorpha, and argued that it shared important cranial and postcranial features with Erpetosuchus; the authors tentatively reassigned Dyoplax to Erpetosuchidae.[1]

Paleoecology

The

bivalves, chondrichthyean fish such as Palaeobates, trematosaurian temnospondyls such as Metoposaurus,[16][17] a phytosaur, and plants such as Neocalamites and Equisetites
were also present in the paleoenvironment that existed at the time.

References

  1. ^
    doi:10.1127/0077-7749/2013/0317
    .
  2. ^ Fraas, Oscar (1867). "Dyoplax arenaceus, ein neuer Stuttgarter Keuper-Saurier". Jahreshefte des Vereins für vaterländische Naturkunde in Württemberg. 23. Stuttgart: 108–112.
  3. ^ Zittel, K. A. von (1890). Handbuch der Palaeontologie. I. Abtheilung Palaeozoologie. III Band. Vertebrata (Pisces, Amphibia, Reptilia, Aves). – XII + 900 pp., 719 figs. München & Leipzig (Oldenbourg).
  4. ^ Huene, F. von (1902). Ubersicht über die Reptilien der Trias. Geol. paläont. Abhandlungen, N. F. 6(1): 1-84; Jena
  5. ^ McGregor, J. H. (1906). The Phytosauria, with especial reference to Mystriosuchus and Rhytidodon. Memoirs of the American Mususeum of Natural History 9:29-101; New York.
  6. ^ Huene, F. von (1942). Lieferungen 3/4. Pseudosuchia, Saurischia, Rhynchosauridae und Schlussabschnitt. Die Fossilen Reptilien des Südamerikanischen Gondwanalandes. Ergebnisse der Sauriergrabungen in Südbrasilien 1928/29. C. H. Beck'sche Verlagsbuchhandlung, München 161-332
  7. Vertebrate Paleontology
    . University of Chicago Press, Chicago; 2nd edition (1945).
  8. ISBN 0-89464-985-X
    .
  9. ISBN 0-7167-1822-7
  10. ISBN 0-7167-1822-7
  11. ^ Benton, M. J. (1994). Late Triassic to Middle Jurassic extinctions among continental tetrapods: Testing thepattern. In: Fraser, N. C. & Sues, H-D. (eds.): In the Shadow of the Dinosaurs: 366-397; Cambridge. Cambridge University Press.
  12. doi:10.1080/02724634.1994.10011552
    .
  13. ^ Lucas, S. G.; Wild, R.; Hunt, A. P. (1998). "Dyoplax O. FRAAS, a Triassic sphenosuchian from Germany" (PDF). Stuttgarter Beiträge zur Naturkunde, B. 263: 1–13.
  14. doi:10.1080/02724634.1992.10011473
    .
  15. doi:10.1080/02724634.1991.10011387
    .
  16. ^ Benton, M. J. (1986). The Late Triassic tetrapod extinction events. In: Padian, K. (ed.): The Beginning of the Age of Dinosaurs: 303-320; Cambridge. Cambridge University Press
  17. ^ Hunt, A. P. (1993). A revision of the Metoposauridae (Amphibia: Temnospondyli) of the Late Triassic with description of a new genus from the western United States. Museum of Northern Arizona Bulletins 59:67-97; Flagstaff

External links

Retrieved from "https://en.wikipedia.org/w/index.php?title=Dyoplax&oldid=1219757303"