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Home / Science / Myocene fossil from Africa provides new evidence for the origin of American crocodiles Paleontology

Myocene fossil from Africa provides new evidence for the origin of American crocodiles Paleontology



A team of paleontologists from Italy and Spain compared the only well-preserved skull Crocodylus checchiai, an extinct species of crocodile that lived in present – day Libya about 7 million years ago (the Miocene era), from those four living species of crocodiles from America, and found that ancient African reptiles are closely related to American crocodiles. The findings suggest that crocodiles may have migrated from Africa to America during the Miocene.

Crocodylus checchiai from As Sahabi, Libya, lifestyle.  Image credit: DA Iurino.

The appearance of life Crocodylus checchiai from As Sahabi, Libya. Image credit: DA Iurino.

Adult skull and associated mandible Crocodylus checchiai were collected in 1938 at the paleontological site of As Sahabi in northern Libya.

An example in 1947. Described by the Italian paleontologist Angiola Maria Maccagno and later held in the collections of the Istituto di Paleontologia dell’Università di Roma.

To improve knowledge of Crocodylus checchiai and possible relationships with American crocodiles, dr. Massimo Delfino from the University of Turin and Barcelona’s Autònoma de Barcelona and colleagues tried to find the original Crocodylus checchiai skull.

Researchers were able to find it in the collection of the Museum of the University of Earth Sciences at Sapienza University in Rome.

They then used computed tomography (CT) to re-examine a well-preserved specimen.

7-million-year-old Crocodylus checchiai skull from As Sahabi, Libya, to dorsal (a1, a2), middle (b1, b2), right lateral (c1, c2), and left lateral (d1, d2).  Anatomical abbreviations: bo - basioccipital, bs - basephenoid, ect - ectopterygoid, en - external member, f - frontal, if - normal foramen, itf - infratemporal fenestra, j - jugal, l - laconic, m - maxilla, n - nasal, o - orbital, pa - parietal, pala - palatine, pf - prefrontal, pm - premaxilla, po - postorbital, pt - pterygoid, q - square, qj - square root, soc - supraccipital, sof - suborbital phenester, kv - squasal, stf - supratemporal fenestra, t - tooth.  Scale bar - 10 cm.  Video credit: Delfino et al., Doi: 10.1038 / s41598-020-68482-5.

7 million years old skull Crocodylus checchiai from As Sahabi, Libya, to the dorsal (a1, a2), middle (b1, b2), right lateral (c1, c2), and left lateral (d1, d2). Anatomical abbreviations: bo – basioccipital, bs – basephenoid, ect – ectopterygoid, en – external member, f – frontal, if – normal foramen, itf – infratemporal fenestra, j – jugal, l – laconic, m – maxilla, n – nasal, o – orbital, pa – parietal, pala – palatine, pf – prefrontal, pm – premaxilla, po – postorbital, pt – pterygoid, q – square, qj – square root, soc – supraccipital, sof – suborbital phenester, kv – squasal, stf – supratemporal fenestra, t – tooth. Scale bar – 10 cm. Video Credit: Dolphin et al, doi: 10.1038 / s41598-020-68482-5.

They identified several new internal structures, including a protrusion in the middle of the muzzle, which was not found for any other African crocodile species.

This unique structure, called the medium rostral bass, is also found in four living species of American crocodiles: Crocodylus intermedius, C. moreletii, C. acutus ir C. rhombifer, and shows a close evolutionary relationship between Crocodylus checchiai and crocodiles from America.

“Analysis of evolutionary relationships between species shows that Crocodylus checchiai may be of the same genus as the four American crocodile species, ”the researchers said.

Residues Crocodylus checchiai dates back about 7 million years, and the oldest extinct remains of American crocodiles Crocodylus falconensis, dating back about 5 million years. “

“Based on these findings, we suggest that crocodiles reach America by migrating west from Australia through Africa.”

The findings were published in the journal Scientific reports.

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M. Delfino et al. 2020 Old African fossils provide new evidence for the origins of American crocodiles. Representative of science 10, 11127; doi: 10.1038 / s41598-020-68482-5


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