Ilchunaia is an extinct genus of sebecid mesoeucrocodylian. Fossils have been found from the Divisadero Largo Formation of Argentina dating back to the Late Eocene,[1][2][3] and a locality in Mendoza, Argentina dating back to the Oligocene.[4][5] Little material is known from the genus, with only the anterior portion of the skull being present to study (the holotype has since been lost).[6][7]

Ilchunaia
Temporal range: Late Eocene (Divisaderan-Tinguirirican)
~37.2–33.9 Ma
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Suborder: Notosuchia
Clade: Sebecosuchia
Clade: Sebecia
Family: Sebecidae
Genus: Ilchunaia
Rusconi, 1946
Type species
Ilchunaia parva
Rusconi, 1946

Taxonomy edit

The placement of Ilchunaia within Sebecosuchidae has been questioned in the past, and many recent phylogenetic analyses have shown the family to be entirely paraphyletic, with members most likely being basal sebecosuchians ancestral to the baurusuchids.[8][9][10][11]

References edit

  1. ^ Ilchunaia at Fossilworks.org
  2. ^ Paolillo, Alfredo; and Linares, Omar J. (2007). Nuevos cocodrilos Sebecosuchia del Cenozoico Suramericano (Mesosuchia: Crocodylia). Paleobiologia Neotropical 3: 1–25.
  3. ^ Turner, A. H. and Calvo, J. O. (2005). A new sebecosuchian crocodyliform from the Late Cretaceous of Patagonia. Journal of Vertebrate Paleontology 25(1):87–98.
  4. ^ Rusconi, C. (1946). Ave y reptil oligocenos de Mendoza. Bolletín Paleontológico (Buenos Aires) 21:1–3.
  5. ^ Langston, W. J. (1956). The Sebecosuchia: cosmopolitan crocodilians? American Journal of Science 254:605–614.
  6. ^ Gasparini, Z., Fernández, M. and Powell, J. (1993). New Tertiary Sebecosuchians (Crocodylomorpha) from South America: Phylogenetic Implications. Hististorical Biology 7:1-19.
  7. ^ Gasparini, Z. (1972). Los Sebecosuchia (Crocodilia) del territorio argentino. Consideraciones sobre su “status” taxonómico. Ameghiniana 9(1): 23-34.
  8. ^ Busbey III, A. B. (1986). New material of Sebecus cf. huilensis (Crocodilia: Sebecosuchia) from the Miocene La Venta Formation of Colombia. Journal of Vertebrate Paleontology 6(1):20-27.
  9. ^ Gasparini, Z., Fernández, M. and Powell, J. (1993). New Tertiary Sebecosuchians (Crocodylomorpha) from South America: Phylogenetic Implications. Hististorical Biology 7:1-19.
  10. ^ Ortega, F., Buscalioni, A. D. and Gasparini, Z. (1996). Reinterpretation and new denomination of Atacisaurus crassiporatus (Middle Eocene; Issel, France) as cf. Iberosuchus (Crocodylomorpha, Metasuchia). Geobios 29:353–364.
  11. ^ Ortega, F., Gasparini, Z., Buscalioni, A. D., and Calvo, J. O. (2000). A new species of Araripesuchus (Crocodylomorpha, Mesoeucrocodylia) from the Lower Cretaceous of Patagonia (Argentina). Journal of Vertebrate Paleontology 20:57–76.

External links edit