From Wikipedia, the free encyclopedia
Taxon of reptiles
Brevirostres is a
paraphyletic group of
crocodilians that included
alligatoroids and
crocodyloids . Brevirostres are crocodilians with small snouts, and are distinguished from the long-snouted
gharials . It is defined
phylogenetically as the
last common ancestor of
Alligator mississippiensis (the American alligator) and
Crocodylus niloticus (the Nile crocodile) and all of its descendants.
[1] This classification was based on
morphological studies primarily focused on analyzing skeletal traits of living and extinct fossil species, and placed the gharials outside the group due to their unique skull structure,
[2] and can be shown in the simplified
cladogram below:
[3]
However, recent molecular studies using
DNA sequencing have rejected Brevirostres upon finding the crocodiles and gavialids to be more closely related than the alligators.
[4]
[5]
[6]
[7]
[8] The new clade
Longirostres was defined by Harshman et al. in 2003,
[4] and can be shown in the cladogram below:
History
Brevirostres was first named by
Karl Alfred von Zittel in 1890. Von Zittel considered
Gavialis , the gharial, to be closely related to
Tomistoma , the false gharial, and excluded them from the group. Tomistoma , as its name implies, is traditionally not considered closely related to Gavialis , but instead classified as a
crocodylid . Under this classification, all members of Brevirostres are brevirostrine, or short-snouted. Recent molecular analyses support von Zittel's classification in placing Tomistoma as a close relative of Gavialis . If this classification is accepted, Brevirostres can be considered redundant with
Crocodylia , as the two names would refer the same clade. Brevirostres would not, however, be a
junior synonym of Crocodylia, as the two names have different definitions.
[9]
References
^ Brochu, C. A. (2003). "Phylogenetic approaches toward crocodylian history". Annual Review of Earth and Planetary Sciences . 31 (31): 357–97.
Bibcode :
2003AREPS..31..357B .
doi :
10.1146/annurev.earth.31.100901.141308 .
^ Holliday, Casey M.; Gardner, Nicholas M. (2012). Farke, Andrew A (ed.).
"A new eusuchian crocodyliform with novel cranial integument and its significance for the origin and evolution of Crocodylia" . PLOS ONE . 7 (1): e30471.
Bibcode :
2012PLoSO...730471H .
doi :
10.1371/journal.pone.0030471 .
PMC
3269432 .
PMID
22303441 .
^ Brochu, C.A. (1997). "A review of "Leidyosuchus" (Crocodyliformes, Eusuchia) from the Cretaceous through Eocene of North America". Journal of Vertebrate Paleontology . 17 (4): 679–697.
Bibcode :
1997JVPal..17..679B .
doi :
10.1080/02724634.1997.10011017 .
JSTOR
4523857 .
^
a
b Harshman, J.; Huddleston, C. J.; Bollback, J. P.; Parsons, T. J.; Braun, M. J. (2003).
"True and false gharials: A nuclear gene phylogeny of crocodylia" (PDF) . Systematic Biology . 52 (3): 386–402.
doi :
10.1080/10635150309323 .
PMID
12775527 . Archived from
the original (PDF) on 2022-10-09. Retrieved 2021-07-19 .
^ Gatesy, J.; Amato, G. (2008). "The rapid accumulation of consistent molecular support for intergeneric crocodylian relationships".
Molecular Phylogenetics and Evolution . 48 (3): 1232–1237.
doi :
10.1016/j.ympev.2008.02.009 .
PMID
18372192 .
^ Erickson, G. M.; Gignac, P. M.; Steppan, S. J.; Lappin, A. K.; Vliet, K. A.; Brueggen, J. A.; Inouye, B. D.; Kledzik, D.; Webb, G. J. W. (2012). Claessens, Leon (ed.).
"Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation" . PLOS ONE . 7 (3): e31781.
Bibcode :
2012PLoSO...731781E .
doi :
10.1371/journal.pone.0031781 .
PMC
3303775 .
PMID
22431965 .
^ 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 .
^ Hekkala, E.; Gatesy, J.; Narechania, A.; Meredith, R.; Russello, M.; Aardema, M. L.; Jensen, E.; Montanari, S.; Brochu, C.; Norell, M.; Amato, G. (2021-04-27).
"Paleogenomics illuminates the evolutionary history of the extinct Holocene "horned" crocodile of Madagascar, Voay robustus" . Communications Biology . 4 (1): 505.
doi :
10.1038/s42003-021-02017-0 .
ISSN
2399-3642 .
PMC
8079395 .
PMID
33907305 .
^ Brochu, C.A. (1999). "Phylogenetics, taxonomy, and historical biogeography of Alligatoroidea". Memoir (Society of Vertebrate Paleontology) . 6 : 9–100.
doi :
10.2307/3889340 .
JSTOR
3889340 .