Brachyuranochampsa

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Brachyuranochampsa
Temporal range: Middle Eocene, 56–33.9  Ma
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
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

Alligatoroidea Alligator white background.jpg

Prodiplocynodon

Asiatosuchus germanicus

"Crocodylus" affinis

"Crocodylus" depressifrons

"Crocodylus" acer

Brachyuranochampsa eversolei

Mekosuchinae

Longirostres
Crocodyloidea

"Crocodylus" megarhinus

Crocodylidae Siamese Crocodile white background.jpg

Gavialoidea

extinct basal Gavialoids

Gavialidae

Gavialis Gavialis gangeticus (Gharial, Gavial) white background.jpg

Tomistoma Tomistoma schlegelii. white background.JPG

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Longirostres Clade of crocodilians

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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.