April 4, 2022 Scott Kraus

Indosuchus is an Abelisaurid

Indosuchus is a prehistoric Theropod dinosaur that roamed the earth 70—65 million years ago.  The name Indosuchus is taken from the Greek Indos and soukhos, respectively meaning “Indian crocodile”.  Indosuchus is a genus of Abelisaurid dinosaur (a family of Ceratosaurian Theropod dinosaurs), and lived during Earth’s Late Cretaceous Period during the Maastrichtian Era.

Quick Facts

About Indosuchus

Indosuchus was a bipedal carnivore (as are most Theropods).  To date, recovery of fossilized remains has been minimal, and accurate classification is elusive.  The type species has been designated as Indosuchus raptorius, and remains attributed to the family group Abelisauridae.

Abelisaurid dinosaurs thrived during the Cretaceous Period, and existed as far back as the Early Jurassic.  This prehistoric dinosaur family lived on the ancient supercontinent of Gondwana, before the phenomenon of plate tectonics separated it into what are now the African and South American continents.  Fossilized remains of various Abelisaurid dinosaurs are found on these continents today, in addition to the Indian subcontinent and Madagascar Isle.

What did Indosuchus Look Like?

Indosuchus resembled other prehistoric bipedal carnivorous dinosaurs, with its large head and tiny front limbs.  This type species especially resembled Indosaurus matleyi, another prehistoric dinosaur found in the same formation.

The bipedal posture of Indosuchus aided its chase for sustenance by powering its stride into the speed necessary for running down its prey and ultimately bringing that prey down.  Being the first feeders on target, these carnivores then used their massive muscular thighs, trunk, neck and head to maintain their feeding position until satiation could take place.  Trespassers were quickly knocked off their target.

Many specific features of Indosuchus remain a mystery, due to the minimal and fragmentary remains found thus far.  As with most Theropods, dinosaurs of the family Abelisauridae had teeth that were useful for tearing flesh and for gripping resistant prey.  The teeth themselves were curved and sharp.  The skull of Indosuchus resembled that of other Abelisaurid dinosaurs, being very tall and almost as short.  The braincase was large.  The eyes sat on the top portion of skull, protected by the lacrimal and postorbital bones which met to form a ridge above and around the eye.

Limbs were reminiscent of other bipedal carnivores, with claws present at the ends of all digits, used for ripping, shredding and digging.  The front limbs were extremely short in comparison to the hind limbs, and the forearm was only 25% or less the length of the upper arm on these type species.  The elbow would have been immobile and the entire arm extended straight and moved about at the shoulder only, if at all in some species.

What did Indosuchus Eat?

Indosuchus benefitted from a dinosaur proliferation that resulted in a vast array of species that it could consider prey.  The long, sharp and serrated teeth of Indosuchus easily made game of most any target.  The species’ physical build was designed for the requirements of spotting, stalking, pouncing and chasing when in pursuit of its meal.  The Cretaceous Period was thick with many prehistoric dinosaur species and other animal species fit for consumption via this particular prehistoric predator.

How did Indosuchus move?

Indosuchus was a bipedal Ceratosaur adapted for running and quick powerful moves.  Its bird-like Ceratosaurian features aided its quickness and ability to gain speed in racing.  Hollow bones, minimal front-end body weight (when compared to the back) except for the balancing and powerful head and neck.  Absence of forelimbs—or rather, presence of vestigial limbs on the front—minimized a lot of weight that would normally restrict bipedal movement.

Where did Indosuchus live?

Indosuchus lived during the latter part of the Cretaceous Period, during the Maastrichtian age.  This was the time at the end of the Mesozoic Era during which many changes were taking place in the evolution of Earth’s physical structure and climate, and subsequently in the inhabiting species of flora and fauna.  Earth was a location of major change during the mass extinction event known as the K-T extinction.  Many dinosaurs lived on Earth during this time; however, their time was limited.  In addition to the catastrophic K-T event, Cretaceous dinosaurs were likely already experiencing background extinction due to the period’s severe climate changes.  There would have been lowered sea levels as the polar ice caps forms, much cooler climates and higher volcanic activity.   These events could be associated with the K-T extinction; however, they are not verified as the final end-all description of events that ultimately caused the mass extinction itself.  It is also theorized that the final cause could have been an asteroid’s impact and the immediate and short-term effects of that impact.

Remains of Indosuchus were found on today’s subcontinent of India, in the Upper Cretaceous layers of the Lameta Formation.  The Lamenta is a sedimentary rock formation found in central-southern India.  Other species are found to have lived in the area, such as titanosaur Isisaurus and abelisaurae Indosaurus, Laevisuchus and Raiasaurus.  Many other finds have been recorded, but are dubious in nature.

The Discovery of Indosuchus

In 1932 near Jabalpur in Madhya Pradesh, India, Charles Alfred Matley found the fragmented and partial remains of a large creature.  Later named by Friedrich von Huene and co-described by Huene and Matley in 1933, Indosuchus raptorius.  It would be many years before I. raptorius would be further classified as a Theropod (dinosaur).

The Indosuchus Jaws

It’s thought that Indosuchus and other ceratosaurian dinosaurs are unique in their characteristic loose attachment between the premaxilla and maxilla—a gap thought to have been fit with large teeth from dentary bone material.  These teeth would have been ultra-efficient in delivering an instant kill result as the predator attacked its prey.