Etjosuchus is an extinct genus of "rauisuchian" (loricatan) archosaur from the Triassic of Namibia. It is known from a single species, Etjosuchus recurvidens, which is based on a partial skeleton from the Ladinian or Carnian-age Omingonde Formation.[1]
| Etjosuchus Temporal range: Middle-Late Triassic, | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Clade: | Archosauria |
| Clade: | Pseudosuchia |
| Clade: | Loricata |
| Genus: | †Etjosuchus Tolchard et al., 2021 |
| Type species | |
| Etjosuchus recurvidens Tolchard et al., 2021 | |
Classification
To evaluate the evolutionary position of Etjosuchus in a modern context, Tolchard et al. (2021) coded it into a phylogenetic matrix derived from the work of Nesbitt (2011). The phylogenetic analysis was run with several levels of implied weighting (from no weighting to k=1, 3, and 6), a strategy to minimize the effects of homoplasy (convergent evolution). With no weighting, Etjosuchus is resolved as a basal loricatan closer to crocodylomorphs than Luperosuchus, but not as close as a Heptasuchus + Batrachotomus clade. At k=1, its position shifts crownward towards crocodylomorphs, and Etjosuchus may clade with Fasolasuchus and/or Rauisuchus. Increasing the weighting further strengthens a connection with Rauisuchus, crownward of Fasolasuchus. This would indicate that the family Rauisuchidae is a paraphyletic grade rather than a clade: Postosuchus and Polonosuchus, other proposed rauisuchids, were closer to crocodylomorphs than to Rauisuchus in this configuration.[1]
