Article · Wikipedia archive · Last revised Jul 8, 2026

Protosuchia

Protosuchia is a group of extinct Mesozoic crocodyliforms. They were small in size and terrestrial. In phylogenetic terms, Protosuchia is considered an informal group because it is a grade of basal crocodyliforms, not a true clade.

Last revised
Jul 8, 2026
Read time
≈ 1 min
Length
281 w
Citations
7
Source
Protosuchia
Temporal range: Late Triassic - Late Cretaceous
A skeleton of Protosuchus richardsoni in the American Museum of Natural History
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauria
Clade: Pseudosuchia
Clade: Crocodylomorpha
Clade: Crocodyliformes
Informal group: Protosuchia
Mook, 1934
Subgroups

See text.

Protosuchia is a group of extinct Mesozoic crocodyliforms. They were small in size (~1 meter in length) and terrestrial. In phylogenetic terms, Protosuchia is considered an informal group because it is a grade of basal crocodyliforms, not a true clade.

Classification

Recent phylogenetic analyses have not supported Protosuchia as a natural group. However, two studies found a clade of Late Triassic-Early Jurassic animals:12

Both of these studies also found a clade more closely related to Hsisosuchus and Mesoeucrocodylia consisting of Late Jurassic-Late Cretaceous genera:12

However, other possible protosuchians from the Late Cretaceous of China-Mongolia, the Gobiosuchidae (Gobiosuchus and Zaraasuchus), have been found to be either intermediate between these two clades,1 or members of the Sichuanosuchus clade.2 There is also another family of Late Jurassic-Late Cretaceous genera, the Shartegosuchidae (e.g. Kyasuchus, Shartegosuchus and Nominosuchus).

Below is a cladogram from Fiorelli and Calvo (2007).2 Protosuchians are marked by the green bracket.

Protosuchians
References

References

  1. Pol D, Ji S-a, Clark JM, Chiappe LM. 2004. Basal crocodyliforms from the Lower Cretaceous Tugulu Group (Xinjiang, China), and the phylogenetic position of Edentosuchus. Cretaceous Research 25: 603-622.
  2. Fiorelli LE, Calvo JO. 2007. The first "protosuchian" (Archosauria: Crocodyliformes) from the Cretaceous (Santonian) of Gondwana. Arquivos do Museu Nacional, Rio de Janeiro 65 (4): 417-459.