According to a new study released this week, a fossil found in the Indian state of Gujarat represents the first nearly complete skeleton of an ichthyosaur from India and the first record from the Jurassic of this country.
Ichthyosaurs. Image credit: Dmitry Bogdanov / CC BY 3.0.
Ichthyosaurs were predatory marine reptiles that ranged in size from 1 to 69 feet (0.3-21 m) long.
They swam the world’s oceans for millions of years during the Triassic, Jurassic and Cretaceous periods.
Despite their profound adaptations to the aquatic realm, these reptiles disappeared about 30 million years before the end-Cretaceous mass extinction (65 million years ago) that marked the end for dinosaurs and the beginning of the age of mammals.
While many ichthyosaur fossils have been found in North American and Europe, in the Southern Hemisphere, their fossil record has mostly been limited to South America and Australia.
Now, Dr. Guntupalli Prasad from the University of Delhi and co-authors report what they believe to be the first Jurassic ichthyosaur found in India.
Field photograph (top) accompanied with a sketch (bottom) of the excavated ichthyosaur skeleton in the Katrol Formation near Lodai village, Kachchh, India. Image credit: Prasad et al, doi: 10.1371/journal.pone.0185851.
The skeleton was found in the Upper Jurassic Katrol Formation exposed at a site south of the village Lodai in Kachchh district, Gujarat.
The specimen is approximately 18 feet (5.5 m long) and belongs to a previously unknown genus and species of the ichthyosaur family Ophthalmosauridae.
It was found among fossils of ammonites and squid-like belemnites, and its tooth wear patterns suggest it predated such hard, abrasive animals.
“This is a remarkable discovery not only because it is the first Jurassic ichthyosaur record from India, but also it throws light on the evolution and diversity of ichthyosaurs in the Indo-Madagascan region of the former Gondwanaland and India’s biological connectivity with other continents in the Jurassic,” Dr. Prasad said.
The study was published online October 25, 2017 in the journal PLoS ONE.
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G.V.R. Prasad et al. 2017. Discovery of the first ichthyosaur from the Jurassic of India: Implications for Gondwanan palaeobiogeography. PLoS ONE 12 (10): e0185851; doi: 10.1371/journal.pone.0185851
