User blog comment:BannedLagiacrus/Discussion of the Week: Extinct and Unknown Status Monsters/@comment-6050823-20140605022950

Things you don't know about the Extinct Monsters and the Unknown Status Monsters(Info from wikiwiki.jp, MH Books from a friend, atwiki.jp

Ancient Serpent/Enshentosapento

Firstly, it has been around since ancient times and has barely changed since those times.

Unlike other Piscine Wyverns, its built for a life completely underwater.

Its legs and wings have completely degenerated but it has some traces of them left.

Pretty much if encountered hunters are requested to kill it because the damage it can do is on par with Elder Dragons.

Bajirisu

Firstly, can't perform the flash like Gypceros and said to be smart like Gypceros.

It evolved from Borudoru and even still has legs similar to Borudoru. Unlike it, is what seems to be a spike or a club on its tail.

Unlike Gypceros, it has scales and a hard shell.

About the Bajirisu/Gypceros situation in MH1's E3 Trailer, it was when they were still trying to decide a design for Gypceros and, were going through trial and error runs trying to decide what Gypceros' final design would be.

Bajirisu appeared at the same as Yian-Kut Ku and Gypceros but sadly went extinct suddenly.

Borudoru

Firstly, Borudoru is larger than Igurueibisu and the ancestor of all winged Bird Wyverns.

Borudoru helped Capcom create Hypnocatrice and Hypnocatrice is believed to be the  direct descendant though Capcom has yet to confirm this.

Canopus

Firstly, Canopus is a relative of the Raths and even lived along side them before becoming extinct at about the same time.

Its shell had multiple ridges yet was quite large from it being one large piece but from this it inhibited some of its movements. It could barely move its long neck and was said to have some problems moving. This alone seems to have what caused them to go extinct.

Igurueibisu

Firstly, it seemed to have appeared first before Wyvern Rex yet they have the same ancestor.

Igurueibisu was a predator thar hunted with its deadly sharp beak and talons while its body was covered in feathers.

Unlike other extinct monsters, full skeletons of these beast have been discovered and the Guild know more about them than other extinct monsters(They maybe lieing).

Igurueibisu is the ancestor of all Bird Wyverns.

Keputosu

Firstly, it is the ancestor of all the raptorial Bird Wyverns.

Keputosu was able to somewhat fly but wasn't able to run like the other raptors could run though it was said it was still evolving strength in its legs.

They disappeared because they couldn't adapt like how the other raptors adapted and become better equiped for hunting along with running. So it could be said that it was outcompeted by them.

Sherureusu

Firstly, its a farther evolved Wyvern Rex and is the ancestor of the Raths.

Sherureusu has a hard shell, long horns, and barbed tail like the Raths. It walks much like Kushala Daora and this is pretty rare for a Flying Wyvern.

They are said to be powerful predators but still went extinct do to environmental changes while some farther changed.

Wyvern Rex

Firstly, Wyvern Rex is the ancestor of all Flying Wyverns.

Its wings are smaller and aren't suitable for flying like Tigrex from fossils the Guild has found.

Wyvern Rex's direct descendant is Tigrex and the Guild discovered this from their spines being identical.