A Late Permian-Early Triassic record of the Ctenacanthiform shark Saivodus sp. From Kashmir, Asia

[Joseph Fossil]

The Ctenacanthiform Sharks are perhaps one of the most famous, yet enigmatic groups of sharks currently known, with a fossil range stretching from the Early Devonian to the Early Cretaceous periods 407.6-136.4 Million Years ago and with a range that spans globally. The most enigmatic along with the most famous genus of Ctenacanthiform (as well as one of my personal favorites) is the genus Saivodus, which was only described properly in 2006 after its fossilized remains were mistaken for two centuries as remains of species belonging to two other Ctenacanthiform genus, Ctenacanthus and Cladodus. The genus Saivodus emerged during the Early Carboniferous 360.7-345.3 Million Years ago and included the largest currently known species of Ctenacanthiformes, the Carboniferous Saivodus striatus that grew up to 35 feet in length fully grown. Despite large numbers of teeth and even very well preserved fossilized remains of the head including jaws and fins from large Saivodus striatus specimens being discovered and described, still very little is known about the overall paleoecology of these enigmatic  sharks.

 

 

Artist reconstruction of an Adult Saivodus striatus and its size compared to an adult Human and adult Great White Shark (Carcharodon carcharias) by artist HodariNundu.
Image Source: https://www.deviantart.com/hodarinundu/art/Super-Sized-Saivodus-866628428

https://paleobiodb.org/classic/basicCollectionSearch?collection_no=84108&is_real_user=1

 

 

The latest record of the genus Saivodus was believed for a few years to be fossils of a small Saivodus sp. from the Fossil Mountain Member of the Kaibab Formation dating to the Kungurian stage of the Permian period 279.3-272.3 Million Years ago in what is now Kachina Village of the U.S. State of Arizona.

 

Hodnett, J. P. M., Elliott, D. K., Olson, T. J., & Wittke J. H. Ctenacanthiform sharks from the Permian Kaibab Formation, northern Arizona. Historical Biology, (2012). 24. 381-395. Retrieved December 16, 2023, from
https://www.researchgate.net/publication/254237970_Ctenacanthiform_sharks_from_the_Permian_Kaibab_Formation_northern_Arizona

https://paleobiodb.org/classic/basicCollectionSearch?collection_no=132088&is_real_user=1

 

 

However, I just found a confirmed (until recently overlooked) record of the genus Saivodus with the assistance of a recent well researched paper on Ctenacanthiform diversity that extends the geological range of genus by around 25.1-20.1 Million Years. I think you’ll all find this record extremely interesting!!!

A Ctenacanthiform tooth were found in 1970 in deposits of the Zewan Formation dating to the Changhsingian stage of the Permian period 254.2-252.2 Million Years ago in what is Guryul Ravine of the region of Kashmir, a disputed territory located at the northernmost point of the Indian Subcontinent of South Asia). This tooth were initially described in 1971 by Paleontologists from Kyoto University, Japan as belonging to a new species of Ctenacanthus, (Ctenacanthus ishii). The size of the tooth is the following:

 

Length of the base of tooth specimen - 16 mm. (1.60 cm.) 

Width of of the tooth's base - 6 mm. (0.60 cm.)

Length/height of each of the tooth's two largest subsidiary or lateral cusps on each side of the tooth - 3.5 mm. (0.35 cm.)

Length/height from the base of the tooth's apex to the top of the tooth's central/medial cusp - 8 mm. (0.80 cm.)

 

Photographs of the Kashmir Saivodus sp. tooth specimen from the Permian-Triassic Zewan Formation, Kashmir, Asia.

Image Source: https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/186572/1/mfskugm 038001_163.pdf

 

 

However, further analysis of the Kashmir specimen in 2021 (including the general tooth shape and morphology) has confirmed the Kashmir tooth is in fact the latest geological record of the Saivodus genus currently known. 

 

Kapoor, H. M,, and Sahni, A. A Shark Tooth from Zewan Series of Guryul Ravine, Kashmir. Memoirs of the Faculty of Science, Kyoto University. Series of Geology and Mineralogy, (1971). 38(1), 163-166. Retrieved December 16, 2023, from
https://repository.kulib.kyoto-u.ac.jp/dspace/bitstream/2433/186572/1/mfskugm 038001_163.pdf

Shah, I. K., Farooq, M., Meraj, G., et al. Geological treasure of Guryul ravine section in Kashmir Himalaya - a case report. ESS Open Archive. (2022). https://doi.org/10.1002/essoar.10510303.1

https://d197for5662m48.cloudfront.net/documents/publicationstatus/75277/preprint_pdf/7673ce9d023bd875199a50b14e3f42e7.pdf

Feichtinger, I., Ivanov, A. O., Winkler, V., Dojen, C., Kindlimann, R., Kriwet, J., Pfaff, C., Schraut, G., & Stumpf, S. Scarce ctenacanthiform sharks from the Mississippian of austria with an analysis of carboniferous elasmobranch diversity in response to climatic and environmental changes. Journal of Vertebrate Paleontology, (2021). 41(2). https://doi.org/10.1080/02724634.2021.1925902

 

 

Not only does this expand the geologic range of Saivodus and is the first confirmed record of this genus from Asia, but the proximity the Kashmir specimen was collected to the location of the Permian-Triassic boundary at the Zewan Formation (only 3 meters away from the geologic boundary) could indicate small to medium species of the genus Saivodus survived the Permian-Triassic Extinction Event 252 Million Years ago and survived (albeit very briefly) into the Early Triassic.

 

This is a major discovery in the study of Ctenacanthiform sharks. Hopefully more specimens of Ctenacanthiform sharks from Permian-Triassic deposits in Kashmir, Pakistan, India, and around the world could be uncovered, studied, and described soon so that we may all get a more accurate understanding of the paleobiology and paleoecology of these amazing prehistoric sharks. This will also give us a more accurate understanding of the fascinating time they lived before one of Earth’s largest mass extinction events along with the period of biological and ecosystem recovery afterwards.