Mamenchisaurus

Mamenchisaurus is a of sauropod dinosaur that lived in the Late Jurassic Period in what is now China. It is best known for its remarkably long neck which made up half its total length.

More real-life information: Mamenchisaurus at Wikipedia.

Jurassic Park Series
Mamenchisaurus was only shown in a short scene in ; it also appears in a couple of games. It replaces Apatosaurus from the second novel.

Movies
Two Mamenchisaurs are seen in, they are the only sauropods featured in this movie. It is believed based on concept art that juvenile sauropods such as Mamenchisaurus were going to be captured by Peter Ludlow in hopes of transferring it to Jurassic Park San Diego, but due to complications were forgotten.

Mamenchisaurus replaces Brachiosaurus on the southern portion Isla Sorna. Their range probably didn't cover the northern part of the island, which probably explains why Grant and the Kirbys didn't see them in. Interestingly, they were shown to hold their necks in a vertical position. However, taking into account how remarkably long their necks are, this position would probably cause a real Mamenchisaurus to faint.

Jurassic Park inspired games
Mamenchisaurus is featured in the arcade game The Lost World: Jurassic Park. In appears in Stage 2 in the Site B Scrub. There is a herd of dinosaurs and you need to drive through without being trampled. First, it lifts its foot and you need to shoot certain spots so it doesn't crush you. You do it again and then the same with the tail, twice. That Mamenchisaurus walks away and there is another one pooping. In order to pass, you need to shoot its poop. If you don't, it'll fling its feces directly at you. The screen will be covered in poop, you will lose a life and the screen will say 'Failed'. The car swerves into a pit of mud, or poop and you will need to fight off raptors.

Mamenchisaurus is nr. 058 of the Herbivore Threes that can be created in Jurassic Park III: Park Builder.

Exhibitions
In the exhibition The Dinosaurs of The Lost World and Jurassic Park the first full-scale Mamenchisaurus was shown.