Crocodylus palaeindicus

Crocodylus palaeindicus
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Crocodylia
Family: Crocodylidae
Genus: Crocodylus
Species:
†C. palaeindicus
Binomial name
†Crocodylus palaeindicus
Falconer, 1859
Synonyms

Crocodylus palaeindicus is an extinct species of crocodile from southern Asia. C. palaeindicus lived from the Miocene to the Pleistocene epoch. It may be an ancestor of the living Mugger crocodile.

History

C. palaeindicus was first named by Scottish paleontologist Hugh Falconer in 1859. Falconer found fossils of the species in the Siwalik Hills of India along with the remains of many other animals like turtles, ostriches, camels, saber-toothed cats, and mastodons.[2] Richard Lydekker later named another crocodile from the Siwalik Hills which he called C. sivalensis. Although the two crocodiles are very similar, C. sivalensis was distinguished from C. palaeindicus because the margin of its skull was less convex. C. sivalensis has recently been synonymized with C. palaeindicus, as the slight differences in shape are thought to be from natural variation or from fossilization.[3] In later years, fossils were also found from Pakistan and Myanmar.

Classification

Historically, C. palaeindicus was considered a direct ancestor of the Mugger crocodile C. palustris. The two species are similar in appearance, and some fossils of C. palaeindicus were at first mistaken for C. palustris.[3] Most modern phylogenetic analyses of crocodiles place C. palaeindicus in a basal position among members of the genus Crocodylus. Below is a cladogram modified from Brochu et al. (2010) showing the relation of C. palaeindicus with other crocodiles:[4]

Crocodylidae

A 2018 tip dating study by Lee & Yates simultaneously using morphological, molecular (DNA sequencing), and stratigraphic (fossil age) data established the inter-relationships within Crocodylidae.[5] In 2021, Hekkala et al. were able to use paleogenomics, extracting DNA from the extinct Voay, to better establish the relationships within Crocodylidae, including the subfamilies Crocodylinae and Osteolaeminae.[6]

The below cladogram shows the results of the latest study:

Crocodylidae
Osteolaeminae

Brochuchus†

Rimasuchus†

Osteolaemus osborni Osborn's dwarf crocodile

Osteolaemus tetraspis Dwarf crocodile

Crocodylinae

Voay†

Crocodylus

Crocodylus palaeindicus†

Crocodylus Tirari Desert†

Asia+Australia

Crocodylus johnstoni Freshwater crocodile

Crocodylus novaeguineae New Guinea crocodile

Crocodylus mindorensis Philippine crocodile

Crocodylus porosus Saltwater crocodile

Crocodylus siamensis Siamese crocodile

Crocodylus palustris Mugger crocodile

Africa+New World

Crocodylus suchus West African crocodile

Crocodylus niloticus Nile crocodile

New World

Crocodylus moreletii Morelet's crocodile

Crocodylus rhombifer Cuban crocodile

Crocodylus intermedius Orinoco crocodile

Crocodylus acutus American crocodile

(crown group)

References

  1. ↑ Chabrol, Nils; Jukar, Advait M.; Patnaik, Rajeev; Mannion, Philip D. (21 March 2024). "Osteology of Crocodylus palaeindicus from the late Miocene-Pleistocene of South Asia and the phylogenetic relationships of crocodyloids". Journal of Systematic Palaeontology. 24 (1) 2313133. doi:10.1080/14772019.2024.2313133.
  2. ↑ Lydekker, R. (1885). Catalogue of the remains of Siwalik Vertebrata contained in the Geological Department of the Indian Museum, Calcutta. Vol. 1. Superintendent of Government Printing, India.
  3. 1 2 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.; Njau, J.; Blumenschine, R. J.; Densmore, L. D. (2010). "A new horned crocodile from the Plio-Pleistocene hominid sites at Olduvai Gorge, Tanzania". PLoS ONE. 5 (2) e9333. Bibcode:2010PLoSO...5.9333B. doi:10.1371/journal.pone.0009333. PMC 2827537. PMID 20195356.
  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.
  6. ↑ 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.