Massetognathinae

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Massetognathinae
Temporal range: Middle Triassic - Late Triassic
Dadadon isaloi.jpg
Skull of the massetognathine Dadadon isaloi
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Clade: Cynodontia
Family: Traversodontidae
Subfamily: Massetognathinae
Kammerer et al., 2012
Genera

See text

Massetognathinae is an extinct subfamily of cynodonts in the family Traversodontidae. It includes four species from the Middle and Late Triassic: Massetognathus pascuali from Argentina, Massetognathus ochagaviae and Santacruzodon hopsoni from southern Brazil, and Dadadon isaloi from Madagascar. [1] Massetognathines have several distinguishing characteristics, including flattened skulls, small canine teeth, and postcanine teeth with three cusps on their outer edges. Massetgognathinae was defined by Kammerer et al. (2012) as the clade containing all traversodontids more closely related to Massetognathus pascuali than to Gomphodontosuchus brasiliensis , and is the sister taxon of the traversodontid subfamily Gomphodontosuchinae, which was defined by Kammerer et al. (2008) as all traverodontids more closely related to G. brasiliensis than to M. pascuali. [2]

Below is a cladogram from Kammerer et al. (2012) showing the phylogenetic position of Massetognathinae within Traversodontidae: [1]

Cynognathia  

Cynognathus

Gomphodontia

Diademodon

Trirachodontidae

Trirachodon

Cricodon

Langbergia

Traversodontidae

Andescynodon

Pascualgnathus

Arctotraversodon

Boreogomphodon

Nanogomphodon

Massetognathinae

Massetognathus

Dadadon

Santacruzodon

Gomphodontosuchinae

Gomphodontosuchus

Menadon

Protuberum

Exaeretodon

Scalenodontoides

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References

  1. 1 2 Kammerer, C. F.; Flynn, J. J.; Ranivoharimanana, L.; Wyss, A. R. (2012). "Ontogeny in the Malagasy Traversodontid Dadadon isaloi and a Reconsideration of its Phylogenetic Relationships". Fieldiana Life and Earth Sciences. 5: 112. doi:10.3158/2158-5520-5.1.112.
  2. Kammerer, C. F.; Flynn, J. J.; Ranivoharimanana, L.; Wyss, A. R. (2008). "New material ofMenadon besairiei(Cynodontia: Traversodontidae) from the Triassic of Madagascar". Journal of Vertebrate Paleontology. 28 (2): 445. doi:10.1671/0272-4634(2008)28[445:NMOMBC]2.0.CO;2.