Nundasuchus

Nundasuchus
Temporal range: Anisian
~247–242 Ma
Pencil sketch of Nundasuchus songeaensis
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Genus: Nundasuchus
Nesbitt et al., 2014
Type species
Nundasuchus songeaensis
Nesbitt et al., 2014

Nundasuchus is an extinct genus of crurotarsan, possibly a suchian archosaur related to Paracrocodylomorpha. Remains of this genus are known from the Middle Triassic Manda beds of southwestern Tanzania. It contains a single species, Nundasuchus songeaensis, known from a single partially complete skeleton, including vertebrae, limb elements, osteoderms, and skull fragments.[1]

Nundasuchus lived in what is now Tanzania, Africa around 240 million years ago. Members of this genus were likely carnivores, around 2.7 to 3 meters (9 feet) long, with ziphodont (steak knife-like) teeth and rows of bony plates (osteoderms) along their back.[2] Phylogenetic analyses consistently place this genus within the group Crurotarsi based on features of the ankle. Most studies also consider it a pseudosuchian, meaning that it was more closely related to modern crocodilians than it was to dinosaurs. However, Nundasuchus had an upright stance, with legs situated directly underneath the body, as with various other early pseudosuchians (such as "rauisuchians" and aetosaurs) but unlike modern crocodilians.

The classification of Nundasuchus relative to other pseudosuchians is somewhat controversial. Some phylogenetic analyses place it near or at the base of the group, sometimes along with phytosaurs, based on certain plesiomorphic (primitive) features such as teeth on the palate, a short pubis, and characteristics of the calcaneum (heel bone).[1][3][4] Another hypothesis, supported by its original 2014 description, considers it to be somewhat more "advanced" than those groups, instead being closer to Ticinosuchus and paracrocodylomorphs (the group containing "rauisuchians" and the ancestors of modern crocodilians). This classification scheme is justified by the presence of "staggered" osteoderms, heart-shaped "spine tables", and a groove on the femoral head. Regardless of these hypotheses, it is clear that Nundasuchus represents a previously unknown group of reptiles with a mixture of features both plesiomorphic and derived with respect to suchian archosaurs.[1]

  1. ^ a b c Nesbitt, Sterling J.; Sidor, Christian A.; Angielczyk, Kenneth D.; Smith, Roger M. H.; Tsuji, Linda A. (November 2014). "A new archosaur from the Manda beds (Anisian, Middle Triassic) of southern Tanzania and its implications for character state optimizations at Archosauria and Pseudosuchia". Journal of Vertebrate Paleontology. 34 (6): 1357–1382. Bibcode:2014JVPal..34.1357N. doi:10.1080/02724634.2014.859622. S2CID 129558756.
  2. ^ "Nundasuchus songeaensis: New Triassic Reptile Discovered in Tanzania | Paleontology | Sci-News.com". Breaking Science News | Sci-News.com. 21 January 2015.
  3. ^ Ezcurra, Martín D. (2016-04-28). "The phylogenetic relationships of basal archosauromorphs, with an emphasis on the systematics of proterosuchian archosauriforms". PeerJ. 4: e1778. doi:10.7717/peerj.1778. ISSN 2167-8359. PMC 4860341. PMID 27162705.
  4. ^ Lúcio Roberto-Da-Silva; Rodrigo Temp Müller; Marco Aurélio Gallo de França; Sérgio Furtado Cabreira; Sérgio Dias-Da-Silva (2018). "An impressive skeleton of the giant top predator Prestosuchus chiniquensis (Pseudosuchia: Loricata) from the Triassic of Southern Brazil, with phylogenetic remarks". Historical Biology: An International Journal of Paleobiology. 32 (7): 1–20. doi:10.1080/08912963.2018.1559841. S2CID 92517047.