Simosuchus

## SimosuchusPug-nosed Crocodile

Possibly lived a burrowing lifestyle

***“ This is Simosuchus. It's not a dinosaur, but a miniature relative of crocodiles, one that lives almost entirely on land, and is strictly vegetarian. ”***

― **David Attenborough**, *Islands*
***Simosuchus*** (Pug-nosed Crocodile) is an extinct genus of ziphosuchian crocodylomorph that lived in the Maevarano Formation, Madagascar, 70 - 66 million years ago, during the Maastrichtian stage of the Late Cretaceous Period. Some fossils of *Simosuchus* have also been found in the Kaveri Basin, south India.

## Description

***“ Simosuchus have tough, armored bodies that protect them from attack by the island's predators, so they can risk dropping their guard... sometimes. ”***

― **David Attenborough**, *Islands*
*Simosuchus* earned its name "pug-nosed crocodile" due to its distinct, short, tall snout, differing from the long, low skulls of other crocodyliforms. This, in combination with its maple leaf-shaped teeth (much like those of herbivorous iguanids), lead paleontologists to believe that it is actually herbivorous. Its tail is also very short, unlike other crocodyliforms. Otherwise, *Simosuchus* is very much like other crocodyliforms, covered with an armor of tightly-interlocked osteoderms, with the osteoderms covering the back, tail, and limbs being light and porous, while those covering the belly are plate-like, with an inner structure resembling that of cancellous bone.

## Habitat

*Main: Maevarano Formation*

Main: Maevarano Formation

***“ The island of Madagascar has been separated from the African mainland for 80 million years, so long that most of its animals are now very different from any to be found elsewhere. ”***

― **David Attenborough**, *Islands*
*Simosuchus* lived 70 - 66 million years ago in the Maevarano Formation in the Mahajanga Province of Madagascar. The Maevarano Formation is recognized as an alluvial plain where the discharge of rivers fluctuate. The area is also believed to have had reddish soil, with floodplains that supported vegetation able to grow in the relatively dry climate. The region, at times semi-arid (like it is today), at times undergoing strong dry and wet seasons, was eventually claimed by rising sea levels that pushed the shoreline back. This may or may not have been the result of the Cretaceous-Paleogene Extinction Event, a catastrophe that wiped out three-quarters of life on Earth.

Some fossils of *Simosuchus* have also been found in the Kaveri Basin of south India.

## Behavior

***“ The Simosuchus have a network of escape routes that lead them to their underground burrows. Once inside, they block the entrance with their heavily-armored backs. ”***

― **David Attenborough**, *Islands*
Prehistoric Planet depicts *Simosuchus* as having social capabilities, able to form small groups, based on how numerous specimens are found together, and how its living relatives were, to a degree, social. In the event of a predator attack, they are also shown to have prepared narrow escape burrows in which they can hide, plugging the entrances with their heavily-armored backs (for a little more security, they can dig even deeper into their burrows to ensure that those hunting them really cannot reach them), based on how they seem to have a few features indicating the ability to dig burrows, and how modern crocodiles can dig tunnels several meters in length. But should one be unlucky to find no vacant burrow to jump into, they can buy time to escape by bluffing in the form of aggressive hisses, tail swipes, kicks, and even running and sliding backwards into predators without actually intending to make contact.

## Appearance

### Islands

In the third segment of the episode, on Madagascar, a *Simosuchus* navigates through an area of plants. It is then shown that they live in a group. One *Simosuchus* reaches up to grab leaves that are out of reach by rearing up and standing on top of another, while some members of the group are shown simply basking under the sun, or sleeping in the shade, not too wary of predators given how their heavily-armored bodies make them feel more secure, unaware that, from afar, a female *Majungasaurus* is observing them. She appears to have dried blood and various wounds on her, and it is revealed that her left eye has gone blind. Due to her disability, she has found it difficult to hunt, and has thus gone very hungry. She finally decides to charge at the group of *Simosuchus*, causing them to run for the burrows they set up beforehand to escape from predators. One male *Simosuchus* ends up unable to find an unoccupied burrow, and is left to face the *Majungasaurus*.

***“ This little male is unlucky. But he's not helpless. Reverse charges, tail swipes, and aggressive kicks. ”***

― **David Attenborough**, *Islands*
With nowhere to run, the *Simosuchus* resorts to bluffing his way out of the situation, with reverse charges, kicks, hisses, and tail swipes, confusing and deterring the *Majungasaurus* long enough for the male to find a vacant burrow to rush for and hide in. The hunter tries to reach into the burrow, but it proves too narrow for her broad snout to fit in. As a safety precaution, the *Simosuchus* digs himself even deeper, getting dirt all over the hunter's face. Dejected and left growling in frustration due to the failure to secure a meal, the *Majungasaurus* walks off. Once the hunter has left, the *Simosuchus* warily walks back out of its burrow, looking around to make sure there are no other threats around before moving on.

## References

### General

1. ↑ 1.0 1.1 1.2 A new Late Cretaceous vertebrate fauna from the Cauvery Basin, South India: implications for Gondwanan paleobiogeography

### Dr. Darren Naish

1. ↑ Because numerous specimens were found close to each other, it is likely that *Simosuchus* is a social animal, much like its still-living relatives today.
2. ↑ A few features suggest that *Simosuchus* is a burrowing animal (though not really a specialized digger as was once believed), and, just as how modern crocodiles can dig deep tunnels, *Simosuchus* may have done the same to avoid harsh weather conditions and predators.