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Data from: Osteology of Crocodylus palaeindicus from the late Miocene–Pleistocene of South Asia and the phylogenetic relationships of crocodyloids

Cite this dataset

Chabrol, Nils; Jukar, Advait M.; Patnaik, Rajeev; Mannion, Philip D. (2024). Data from: Osteology of Crocodylus palaeindicus from the late Miocene–Pleistocene of South Asia and the phylogenetic relationships of crocodyloids [Dataset]. Dryad. https://doi.org/10.5061/dryad.83bk3j9z8

Abstract

Fossil crocodylian remains have been documented from India and other parts of South Asia since the mid-19th century, but specimens attributed to several extinct and extant species of Crocodylus have largely been neglected in modern taxonomic treatments. Here, we present a detailed anatomical description of the extinct species Crocodylus palaeindicus, which we restrict to the Late Miocene to early Middle Pleistocene of India. Using an autapomorphy-based approach to species-level identification, we regard Crocodylus sivalensis as a junior synonym of C. palaeindicus, and provide taxonomic reidentifications of all specimens previously referred to these two species. We present a new diagnosis for C. palaeindicus that facilitates its distinction from the extant mugger crocodile, C. palustris, which does not unequivocally appear in the fossil record prior to the Pleistocene. The lack of clear spatiotemporal overlap, coupled with the otherwise lengthy ghost lineage implied by their sister taxon relationship in our phylogenetic analyses, provides tentative support that the extant species is either the descendant of C. palaeindicus, or originated via budding cladogenesis. An expanded phylogenetic analysis recovers the Late Miocene African C. checchiai and Pliocene South American C. falconensis as species within the Neotropical Crocodylus clade, supporting an African origin for this radiation. We also recover Kinyang, from the early–middle Miocene of Kenya, as a crocodyline, rather than an osteolaemine as originally described, and it is potentially the stratigraphically earliest known member of the Crocodylus lineage. Other notable results from our phylogenetic analyses suggest that crocodyloids might not have been present in North America prior to the late Neogene arrival of Crocodylus, with Albertosuchus knudsenii, Prodiplocynodon langi, and ‘Crocodylusaffinis all recovered outside of Crocodyloidea. Furthermore, we demonstrate that an alligatoroid placement for the recently erected latest Cretaceous–Paleogene East Asian clade Orientalosuchina is highly labile, with relationships at the ‘base’ of Crocodylia unstable.

README: Osteology of Crocodylus palaeindicus from the late Miocene–Pleistocene of South Asia and the phylogenetic relationships of crocodyloids

https://doi.org/10.5061/dryad.83bk3j9z8

Description of the data and file structure

The data are separated into 4 files :
- nexus_matrix.nex which is the morphological data matrix used in the analyses.
- tnt_matrix.tnt which is the same matrix but in a format suitable for running the analyses under the TNT software.
- tree_analysis_1.nex which is the output tree of analysis 1.
- tree_analysis_2.nex which is the output tree of analysis 2.

Methods

The morphological data matrix was built based on the literature and personal observations. These data were then analysed under the TNT (v. 1.6) software for phylogenetic inferences with several methods of inference.

Funding

Office of the Royal Society, Award: UF160216

Office of the Royal Society, Award: URF\R\221010

Leverhulme Trust, Award: RPG-2021-202