Crocodyloidea

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Superfamily of crocodiles

title: "Crocodyloidea" type: doc version: 1 created: 2026-02-28 author: "Wikipedia contributors" status: active scope: public tags: ["crocodyloidea", "extant-campanian-first-appearances"] description: "Superfamily of crocodiles" topic_path: "general/crocodyloidea" source: "https://en.wikipedia.org/wiki/Crocodyloidea" license: "CC BY-SA 4.0" wikipedia_page_id: 0 wikipedia_revision_id: 0

::summary Superfamily of crocodiles ::

| name = Crocodyloidea | taxon = Crocodyloidea | image = Nilecroc100.jpg | image_caption = Crocodylus niloticus (Nile crocodile) | fossil_range = | authority = Fitzinger, 1826 | subdivision_ranks = Subgroups | subdivision =

Crocodyloidea is one of three superfamilies of crocodilians, the other two being Alligatoroidea and Gavialoidea, and it includes the crocodiles. Crocodyloidea may also include the extinct Mekosuchinae, native to Australasia from the Eocene to the Holocene, although this is disputed.

Classification

Cladistically, it is defined as Crocodylus niloticus (the Nile crocodile) and all crocodylians more closely related to C. niloticus than to either Alligator mississippiensis (the American alligator) or Gavialis gangeticus (the gharial). This is a stem-based definition for crocodiles, and is more inclusive than the crown group Crocodylidae. As a crown group, Crocodylidae only includes the last common ancestor of all extant (living) crocodiles and their descendants (living or extinct), whereas Crocodyloidea, as a stem group, also includes more basal extinct crocodile ancestors that are more closely related to living crocodiles than to alligators or gavialids. When considering only living taxa (neontology), this makes Crocodyloidea and Crocodylidae synonymous, and only Crocodylidae is used. Thus, Crocodyloidea is only used in the context of paleontology.

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. However, recent molecular studies using DNA sequencing have rejected Brevirostres upon finding the crocodiles and gavialids to be more closely related than the alligators. The new clade Longirostres was named by Harshman et al. in 2003.

A 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data established the inter-relationships within Crocodilia, which was expanded upon in 2021 by Hekkala et al. using paleogenomics by extracting DNA from the extinct Voay.

The below cladogram shows the results of the latest study, and how Crocodyloidea may only contain one additional taxon beyond Crocodylidae:

|label1=Crocodylia |sublabel1=(crown group) |1={{clade |label1=Alligatoroidea |sublabel1=(stem-based group) |1={{clade |1=extinct basal Alligatoroids |label2=Alligatoridae |sublabel2=(crown group) |2={{clade |label1=Caimaninae |1={{clade |1={{clade |1=Caiman [[File:Caiman crocodilus llanos white background.JPG|90 px]] |2=Melanosuchus [[File:Melanosuchus niger white background.jpg|120 px]] }} |2=Paleosuchus [[File:Dwarf Caiman white background.jpg|90 px]] }} |label2=Alligatorinae |2=Alligator [[File:Alligator white background.jpg|100 px]] }} }} |2={{clade |1=extinct basal Crocodilians (including Mekosuchinae) |label2=Longirostres |sublabel2=(crown group) |2={{clade |label1=Crocodyloidea |sublabel1=(stem-based group) |1={{clade |1="Crocodylus" megarhinus |label2=Crocodylidae |sublabel2=(crown group) |2={{clade |1=Crocodylus [[File:Siamese Crocodile white background.jpg|90 px]] |2={{clade |1=Mecistops [[File:Crocodylus cataphractus faux-gavial d'Afrique2 white background.JPG|90 px]] |2=Osteolaemus [[File:Bristol.zoo.westafrican.dwarf.croc.arp. white background.jpg|90 px]] }} }} }} |label2=Gavialoidea |sublabel2=(stem-based group) |2={{clade |1=extinct basal Gavialoids |label2=Gavialidae |sublabel2=(crown group) |2={{clade |1=Gavialis [[File:Gavialis gangeticus (Gharial, Gavial) white background.jpg|110 px]] |2=Tomistoma [[File:Tomistoma schlegelii. white background.JPG|90 px]]

References

References

  1. (2017). "Variation in the pelvic and pectoral girdles of Australian Oligo–Miocene mekosuchine crocodiles with implications for locomotion and habitus". PeerJ.
  2. (2019). "Mosaic nature in the skeleton of East Asian crocodylians fills the morphological gap between "Tomistominae" and Gavialinae". Cladistics.
  3. Brochu, Christopher A.. (May 2003). "Phylogenetic approaches toward crocodylian history". Annual Review of Earth and Planetary Sciences.
  4. Michael S. Y. Lee. (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]].
  5. Holliday, Casey M.. (2012). "A new eusuchian crocodyliform with novel cranial integument and its significance for the origin and evolution of Crocodylia". PLOS ONE.
  6. (2003). "True and false gharials: A nuclear gene phylogeny of crocodylia". Systematic Biology.
  7. (2008). "The rapid accumulation of consistent molecular support for intergeneric crocodylian relationships". [[Molecular Phylogenetics and Evolution]].
  8. Erickson, G. M.. (2012). "Insights into the ecology and evolutionary success of crocodilians revealed through bite-force and tooth-pressure experimentation". PLOS ONE.
  9. (2021-04-27). "Paleogenomics illuminates the evolutionary history of the extinct Holocene "horned" crocodile of Madagascar, Voay robustus". Communications Biology.

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