Longirostres

Longirostres Temporal range: Late Cretaceous - Recent, 70.6–0 Ma PreꞒ Ꞓ O S D C P T J K Pg N
Nile crocodile (Crocodylus niloticus)
Gharial (Gavialis gangeticus)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Crocodilia
Clade:	Longirostres Zittel, 1890
Subgroups
Crocodyloidea Crocodylidae †"Crocodylus" megarhinus †Mekosuchinae? Gavialoidea Gavialidae †Kentisuchus †Paratomistoma †Maroccosuchus †Dollosuchoides

Longirostres is a clade of crocodilians that includes the crocodiles and the gavialids, to the exclusion of the alligatoroids. Defined in 2003 by Harshman et al., Longirostres is a crown group defined phylogenetically as including the last common ancestor of Crocodylus niloticus and Gavialis gangeticus and all of its descendants.^[1]

Traditionally, crocodiles and alligators were considered more closely related and grouped together in the clade Brevirostres, to the exclusion of the gharials. This classification was based on morphological studies primarily focused on analyzing skeletal traits of living and extinct fossil species.^[2] However, recent molecular studies using DNA sequencing have rejected Brevirostres upon finding the crocodiles and gavialids to be more closely related than the alligators.^{[1][3][4][5][6]}

Below is a cladogram showing the relationships of the major crocodilian groups based on molecular studies:^[5][6]

Crocodylia

Alligatoroidea extinct basal Alligatoroids† Alligatoridae Caimaninae Caiman Melanosuchus Paleosuchus Alligatorinae Alligator (crown group) (stem-based group) extinct basal Crocodilians† (including Mekosuchinae†) Longirostres Crocodyloidea extinct basal crocodiles† Crocodylidae Crocodylus Mecistops Osteolaemus (crown group) (stem-based group) Gavialoidea extinct basal Gavialoids† Gavialidae Gavialis Tomistoma (crown group) (stem-based group) (crown group)

(crown group)

References

This page was last edited on 20 June 2023, at 19:26