Notosuchus Explained

Notosuchus (; 'southern crocodile') is an extinct genus of South American notosuchian crocodyliforms. It was terrestrial, living approximately 85 million years ago in the Santonian stage of the Late Cretaceous.[1]

Description

Notosuchus was relatively small, reaching 1.5m (04.9feet) in length and a weight of 36kg (79lb).[2] Remains have been found in the Bajo de la Carpa Formation in Patagonia, Argentina. First named in 1896, Notosuchus was the first known notosuchian.[3] The type species is N. terrestris. A second species, N. lepidus, was named in 1957.[4]

A paper published in 2008 by Fiorelli and Calvo described new remains of the type species N. terrestris.[5] In it, the authors suggested that the skull would have supported a short trunk, or "hog's snout" as well as fleshy upper and lower lips. The anteriorly directed nares and the absence of a bony nasal septum (which presumably indicates cartilaginous tissue serving its place) provide evidence for a trunk-like snout, while striations on the surface of the nasal bones and the lower jaw most likely acted as attachment points for the nasolabial muscles and the depressor muscle, respectively.[6] Additionally, the authors suggested that a lateral rim on the dentary as well as numerous aligned neurovascular foramina are evidence of soft cheek-like muscular tissue. The function of the trunk was likely used for searching for food by sniffing the ground in a manner similar to extant suids and peccaries, while the cheeks would aid in mastication by preventing food loss.[5] A re-description of the skull material has since lent evidence toward minimal soft-tissue enhancement to the snout of Notosuchus.[7]

Notes and References

  1. Hugo . CA . Leanza . HA . 2001 . Hoja Geológica 3969-IV, General Roca. Provincias de Río Negro y Neuquén . Boletín Servicio Geológico Minero Argentino, Instituto de Geología y Recursos Minerales . 308 . 1–65 .
  2. Web site: Notosuchus - paleofiles.com.
  3. Woodward . AS . 1896 . On Two Mesozoic Crocodilians Notosuchus (Genus Novum) and Cynodontosuchus (Genus Novum) from the Red Sandstone of the Territory of Neuquen (Argentine Republic) . Anales del Museo de la Plata, Paleontologia Argentina . 6 . 1–20 .
  4. Saez . MD . 1957 . Crocodiloideos Fosiles Argentinos un nuevo Crocodilo del Mesozoico Argentino . Ameghiniana . 1–2 . 49–50 .
  5. Fiorelli . L. E. . Calvo, J. O. . 2008 . New remains of Notosuchus terrestris Woodward, 1896 (Crocodyliformes: Mesoeucrocodylia) from Late Cretaceous of Neuquen, Patagonia, Argentina . Arquivos do Museu Nacional, Rio de Janeiro . 66 . 1 . 83–124.
  6. Fiorelli, L. E. (2005). "Nuevos restos de Notosuchus terrestris Woodward, 1896 (Crocodyliformes: Mesoeucrocodylia) del Cretácico Superior (Santoniano) de la Provincia de Neuquén, Patagonia, Argentina". 79p. Tesis (Grado) Universidad Nacional de Córdoba, Córdoba.
  7. Barrios . F. . Bona . P . Carabajal . A.P. . Gasparini . Z.. 2017 . Re-description of the cranio-mandibular anatomy of Notosuchus terrestris (Crocodyliformes, Mesoeucrocodylia) from the Upper Cretaceous of Patagonia . Cretaceous Research . 83 . 3–39 . 10.1016/j.cretres.2017.08.016. 11336/32766 . free .