![The size of a tractor-trailer, the model of a young adult female Mamenchisaurus features skin texture on one side and video projections on the other side.](http://assets.dnainfo.com/generated/sfb111/story_xlimage_2011_05_R1582_Name_That_Dino_Contest_at_AMNH_051811.jpg/larger.jpg)
By Leslie Albrecht
DNAinfo Reporter/Producer
UPPER WEST SIDE — What do you call an 18-year-old vegetarian dinosaur with a 30-foot neck? Send suggestions to the American Museum of Natural History.
The museum is holding a naming contest for its Mamenchisaurus dinosaur, the centerpiece of its new World's Largest Dinosaurs exhibit.
The dinosaur's given name is a mouthful that doesn't exactly roll off the tongue, said the museum spokeswoman Anne Canty. So the museum is looking for a catchy nickname.
"Mamenchisaurus" is also not ideal for Twitter, which museum staff have been using to broadcast the mega dino's surprisingly rich inner life. Sample Tweet: "Ok, I know I don’t have any predators, but I still get paranoid every #friday13th."
![Though its body weighed 13 tons, the Mamenchisaurus’ tiny head was surprisingly light, perhaps only 45 pounds.](http://assets.dnainfo.com/generated/sfb111/story_xlimage_2011_05_R6531_Name_That_Dino_Contest_at_AMNH_051811.jpg/larger.jpg)
Museum-goers have been enchanted by Mamenchisaurus, a type of dinosaur called a sauropod that roamed the Earth about 165 million years ago, Canty said.
That could be because the World's Largest Dinosaurs exhibit focuses on how dinosaurs lived and breathed, not on their bones, Canty said.
"In this show there are hardly any fossils and bones because it's really about the way dinosaurs lived," Canty said. "People have come away really fascinated with this animal."
Canty said the museum is looking for creative name suggestions that "befit the dignity" of the massive Mamenchisaurus, which scientists believe ate about 100,000 calories a day, or about 1,150 pounds of plant matter.
"She's an actual animal that lived 165 million years ago," Canty said. "She's very important and she has a lot of history we want it be a name that fits her."
The naming contest runs until May 25. Submissions can be made on the museum's website. Three finalists win a "a giant dinosaur prize package" from the museum, and one winner will receive an iPod touch.