Madtsoia

Madtsoianamed after "Cow Valley"
Classification
Domain	Eukaryota
Kingdom	Animalia
Phylum	Chordata
Subphylum	Vertebrata
Superclass	Tetrapoda
Clade	Sauropsida
Class	Reptilia
Clade	Lepidosauromorpha
Superorder	Lepidosauria
Order	Squamata
Clade	Ophidia
Family	Madtsoiidae (paraphyletic?)
Species	Madtsoia madagascariensis
Presence
Location	Maevarano Formation, Mahajanga Province, Northwest Madagascar
Temporal Range	90 - 34 million years ago, Coniacian - Priabonian Stage, Late Cretaceous - Late Eocene Period
Episodes	Islands (Segment 4)
Characteristics
Length	5.1 – 8 meters (17–26 feet)
Mass	50 kilograms (110 pounds)
Diet	Carnivorous
Kills prey via constriction, much like modern-day pythons (to which it is unrelated to)

Madtsoia (Tehuelche for "Cow Valley", the place it was first found in) is an extinct genus of madtsoiid snake that lived in Africa, India, and South America, around 90 - 34 million years ago, from the Coniacian stage of the Late Cretaceous Period to the Priabonian age of the Late Eocene Period. The species depicted on Prehistoric Planet is Madtsoia madagascariensis, which lived in the Maevarano Formation of the Mahajanga Province (known as "Majunga" in French) in northwest Madagascar, 72 - 66 million years ago, during the Maastrichtian stage of the Late Cretaceous Period.

Paleobiology

Madtsoia resembles a modern-day python, though it is unrelated to them. The species shown on Prehistoric Planet, M. madagascariensis, was 5.1 - 8 meters (17 - 26 feet) long, and weighed around 50 kilograms (110 pounds).

Paleoecology

Paleoenvironment

Main: Maevarano Formation

Main: Maevarano Formation

Madtsoia searching for prey during the night

Madtsoia lived in Niger, Spain, Madagascar, India, Argentina, and Brazil during various times in Earth's history. It may have been around since the Coniacian stage of the Late Cretaceous Period, approximately 90 - 86 million years ago.

The species depicted on the show, M. madagascariensis, lived in the Maevarano Formation in the Mahajanga Province of Madagascar, 72 - 66 million years ago, during the Maastrichtian, the last stage of the Late Cretaceous Period. 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), 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 disaster that wiped out three-quarters of life on Earth. The devastating catastrophe may or may not have killed off M. madagascariensis and another species from the Lameta Formation in India, M. pisdurensis.

Nevertheless, the Madtsoia genus as a whole survived and continued existing millions of years after the Cretaceous-Paleogene Extinction Event, until the last of them, M. bai and another, indeterminate Madtsoia species, died out 48 million years ago in the Cañadón de las Vacas (Valley of the Cows), a locality within the Sarmiento Formation of the Chubut Province of Argentina (though there are supposedly Madtsoia remains to be found up until 34 million years ago). Ironically, the first Madtsoia fossils would be found here, hence, it - and by extension, its (possibly paraphyletic) family - was named after the Cañadón de las Vacas locality, which can be roughly translated as "Mad Tsoi" (Cow Valley) in the language of the native Tehuelche people.

Thermoregulation, Hunting Tactics, and Feeding Preferences

Madtsoia constricts a Masiakasaurus to death

“ Madtsoia, a snake nearly 25 feet long, squeezes its prey to death. ”

― David Attenborough, Islands

As an ophidian squamate (snake), Madtsoia is almost certainly a poikilotherm (equivalent to the outdated concept of "cold-bloodedness"), reliant on its surroundings to regulate its body temperature since it cannot generate its own heat, with slow metabolism to match. For this reason, snakes rely on ambush, patiently waiting for prey to approach their location, to conserve effort and energy. Madtsoia, like other madtsoiids, is believed to have suffocated its prey by wrapping around them with tight coils, similar to the modern constrictor snakes that madtsoiids are believed to be analogous to, though madtsoiids can be differentiated from extant constrictors by their more primitive jaws, which cannot unhinge to the same extent as modern-day boas and pythons, hence, small dinosaurs like Masiakasaurus would have been the largest prey that Madtsoia can tackle. The slow metabolism of snakes does have its benefits, as it allows them to go for long periods without food, the amount of time between meals depending on the size of the prey they consume.

Appearance

A Madtsoia lunges at a Masiakasaurus

In the fourth segment of Islands, the eye of a snake is first seen as a mother Adalatherium is out foraging for food at night. The morning after, while a Masiakasaurus was looking for prey, nearly coming upon the burrow in which the Adalatherium's cubs were sleeping, a serpent lunges at the theropod and constricts it to death.

“ This neighborhood has now become rather dangerous. As night falls, the mother leads her young out of the burrow for the very first time. For now, at least, they must stay close together. ”

― David Attenborough, Islands

Witnessing this, the mother Adalatherium deems that the area has become too dangerous, and, by night, moves out of her burrow along with her ten cubs. One of the cubs briefly looks back and finds the Madtsoia resting on a fallen tree branch, staring back at it. With this, the Adalatherium cub turns back around and continues to follow its mother as they move far away from the area.