Acynodon is an extinct genus of alligatoroid crocodilian. When first described it was placed within the family Alligatoridae,[1] but has since been reclassified as a globidontan. It is the oldest and most primitive globidontan known to date,[2] with fossils being found from France, Spain, Italy, and Slovenia. Acynodon first appeared during the early Campanian stage of the Late Cretaceous and became extinct during the Cretaceous–Paleogene extinction event at the Cretaceous–Paleogene boundary. The skull of Acynodon is extremely brevirostrine; it had a very short and broad snout compared to other known alligatorids.[3] Its dentition was quite derived, with enlarged molariform teeth and a lack of maxillary and dentary caniniform teeth, presumably an adaptation to feed on slow prey with hard shells.[2] The paravertebral osteoderms of Acynodon were distinctively double-keeled.

Temporal range: 83.5–66 Ma
Early Campanian - Late Maastrichtian
Skull of Acynodon iberoccitanus (ACAP-FXl)
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Crocodilia
Clade: Globidonta
Genus: Acynodon
Buscalioni et al., 1997
  • A. iberoccitanus Buscalioni et al., 1997 (type)
  • A. adriaticus Delfino et al., 2008
  • A. lopezi Buscalioni et al., 1997


  1. ^ Buscalioni, A. D.; Ortega, F. L.; Vasse, D. (1997). "New crocodiles (Eusuchia: Alligatoroidea) from the Upper Cretaceous of southern Europe". Comptes Rendus de l'Académie des Sciences, Série IIA. 325: 525–530.
  2. ^ a b Delfino, M.; Martin, J. E.; Buffetaut, E. (2008). "A new species of Acynodon (Crocodylia) from the Upper Cretaceous (Santonian-Campanian) of Villaggio del Pescatore, Italy". Palaeontology. 51 (5): 1091–1106. doi:10.1111/j.1475-4983.2008.00800.x.
  3. ^ Martin, J. E. (2007). "New material of the Late Cretaceous globidontan Acynodon iberoccitanus (crocodylia) from Southern France". Journal of Vertebrate Paleontology. 27 (2): 362–372. doi:10.1671/0272-4634(2007)27[362:NMOTLC]2.0.CO;2.

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Extinct crocodilian species


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