Brachyuranochampsa

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Brachyuranochampsa
Temporal range: Middle Eocene, 56–33.9  Ma
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Clade: Archosauromorpha
Clade: Archosauriformes
Order: Crocodilia
Genus: Brachyuranochampsa
Zangerl, 1944
Species
  • B. eversoleiZangerl, 1944 (type)

Brachyuranochampsa is an extinct genus of crocodilian.

The only robust occurrence of Brachyuranochampsa is B. eversolei from the Middle Eocene of Wyoming. [1] Another species, B. zangerli from the lower Bridger Formation at Grizzly Buttes, has been synonymized with another primitive crocodilian, "Crocodylus" affinis , also known from the Bridger Formation. [2] [3]

Phylogenetic studies have consistently recovered Brachyuranochampsa as more basal than the crown group Crocodylidae, which consists of all extant (living) crocodiles. [2] [4]

The below cladogram from a 2018 study combining morphological data and molecular DNA evidence shows the placement of Brachyuranochampsa within Crocodylia. [5]

Crocodylia

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References

  1. Zangerl, R. (1944). Brachyuranochampsa eversolei, gen. et sp. nov., a new crocodilian from the Washakie beds of Wyoming. Annals of Carnegie Museum, 30:77-84
  2. 1 2 Brochu, C. A. (1997). "Morphology, fossils, divergence timing, and the phylogenetic relationships of Gavialis". Systematic Biology . 46 (3): 479–522. doi: 10.1093/sysbio/46.3.479 .
  3. Brochu, C. A. (2000). "Phylogenetic relationships and divergence timing of Crocodylus based on morphology and the fossil record". Copeia . 2000 (3): 657–673. doi:10.1643/0045-8511(2000)000[0657:pradto]2.0.co;2.
  4. Brochu, C. A.; Storrs, G. W. (2012). "A giant crocodile from the Plio-Pleistocene of Kenya, the phylogenetic relationships of Neogene African crocodylines, and the antiquity of Crocodylus in Africa". Journal of Vertebrate Paleontology . 32 (3): 587. doi:10.1080/02724634.2012.652324.
  5. Michael S. Y. Lee; Adam M. Yates (27 June 2018). "Tip-dating and homoplasy: reconciling the shallow molecular divergences of modern gharials with their long fossil". Proceedings of the Royal Society B . 285 (1881). doi: 10.1098/rspb.2018.1071 . PMC   6030529 . PMID   30051855.