Late Maastrichtian Cretaceous Vertebrate Fauna From India has Enormous Implications

A new Late Cretaceous vertebrate fauna from the Cauvery Basin, South India: implications for Gondwanan paleobiogeography

Authors:

Guntupalli V. R. Prasad, Omkar Verma, John J. Flynn & Anjali Goswami

Abstract:

Late Cretaceous vertebrate faunas of India are known predominantly from intertrappean deposits in the Deccan volcanic province of the central and western parts of the country. A thick and nearly continuous sequence of Early Cretaceous–Early Paleocene fossiliferous sediments exposed in the Cauvery Basin of South India has been comparatively poorly explored. Here, we present a preliminary description of a new fauna consisting of vertebrate fossils discovered from the continental Upper Cretaceous (late Maastrichtian) Kallamedu Formation. The Kallamedu Fauna includes ganoid fishes, amphibians, turtles, crocodiles, and dinosaurs, with many taxa suggesting Late Cretaceous biotic links between India and other Gondwanan landmasses. Teeth of abelisaurid dinosaurs, known previously from the Middle Jurassic of South America and the Late Cretaceous of Africa, Madagascar, and central and western India, support a pan-Gondwanan distribution for this group of theropod dinosaurs. Of greatest significance, however, is the first discovery of a Simosuchus-like notosuchian crocodile outside of Madagascar. This report of the first Indian Simosuchus-like notosuchian crocodile further strengthens earlier evidence from other vertebrate groups for close biotic links between India and Madagascar in the Late Cretaceous, most likely through dispersal via the Seychelles block, Amirante Ridge, and Providence Bank.

There are multiple implications here.

1. The one covered directly in the paper.  That is to say, there were links with the rest of Gondwana during the late Maastrichtian and especially with Madagascar.  This is probably through island hopping rather than land bridges.

2.  And this is the one which really interests me.  There was a healthy, diverse dinosaur filled ecology at ground zero for the Deccan Traps while the Deccan Traps were erupting.  Ruminate on that.  Seriously. The vulcanists might have just taken it in the shorts again.

3.  WE HAVE A NEW TERRESTRIAL CONTIGUOUS SECTION ACROSS THE K-T/K-Pg Boundar.  Hell Creek, you have a buddy now.  This is enormously important.  And I bet we'll see it studied as all get out to compare to the North American locality.  Our sample size will have just jumped from one to two.  ;)