恐龍卡第 1153 張，共 2 027 張

Megalneusaurus

名字的意思： “king of large swimming lizards”1

吃：肉蛇頸龍類侏羅紀晚期嚴格來說不是恐龍

Megalneusaurus was a giant marine reptile that swam in the shallow Sundance Sea during the Late Jurassic. It was one of the biggest predators in North America at that time, with four flippers and a big head.1

趣味小知識：這種海生爬蟲類在海裡游泳的時候，恐龍正在陸地上走路。大家都叫牠們恐龍，但牠們其實是爬蟲類的另一個分支。

生存年代

162 到 155 百萬年前3

侏羅紀晚期

化石發現地

Wyoming, USA, and possibly Alaska, USA1

長度

7 到 9 m (23 到 30 ft)1

最高速度

時速約 23 公里（14 英里）

游泳, 估計值

牠生活在什麼時候？

三疊紀

侏羅紀

白堊紀

2 億 5200 萬年前20114566，小行星撞地球

牠有多大？

牠有多長？

跟 2 台汽車排成一排一樣長跟 50 根香蕉頭尾相接一樣長能在 7.8 秒內游完一座大泳池（50 公尺）

Megalneusaurus 跟「你」比起來有多大？

只是在你的瀏覽器裡算算數學。什麼都不會被儲存或傳送出去。

牠有多快？

走路的人 時速約 5 公里 (3 mph)

騎腳踏車的小朋友 時速約 12 公里 (7 mph)

Megalneusaurus 時速約 23 公里 (14 mph)

一匹飛奔的馬 時速約 65 公里 (40 mph)

一隻獵豹 時速約 100 公里 (62 mph)

酷東西

趣味知識

Megalneusaurus was one of the largest pliosaurs in North America, measuring about 7 to 9 meters (23 to 30 feet) long.1

Its back flippers were bigger than its front flippers, which is unusual for plesiosaurs.1

Fossil stomach contents include tiny hooks from squid-like animals and bits of fish bones.1 2

It lived in the Sundance Sea, a shallow sea that covered parts of North America during the Jurassic.1

Scientists think it was an ambush predator, waiting to surprise its prey.1

A specimen from Alaska suggests it could also live in colder waters.1

Megalneusaurus 的 AI 繪圖 — 這是電腦根據科學家目前的知識，用 AI 畫出 Megalneusaurus 可能的樣子。這只是猜測：真正的動物可能長得不一樣，也沒有人知道牠真正的顏色。

你們都在問

關於 Megalneusaurus 最常被問的問題

?How big was Megalneusaurus?

Megalneusaurus was about 7 to 9 meters (23 to 30 feet) long. Some estimates say it could reach around 13 meters (43 feet).1

?What did Megalneusaurus eat?

It ate squid-like animals and fish, based on hooklets and fish bones found in its stomach. It may also have eaten other plesiosaurs.1 2

?Could Megalneusaurus live in cold water?

Yes. A specimen found in Alaska shows it could live in colder waters, where there were fewer animals.1

?Was Megalneusaurus a dinosaur?

No, it was a marine reptile called a pliosaur, not a dinosaur. It lived in the sea.1

迷思破解王

迷思： Some people think Megalneusaurus was a dinosaur.

真相： It was a plesiosaur, a marine reptile, not a dinosaur.1

給恐龍專家

學名: Megalneusaurus
命名者: Knight 18983
類群: 蛇頸龍類
科 / 演化支: Plesiosauria3
分類: Plesiosauria > Sauropterygia3
岩石的年代: 162 到 155 百萬年 (Oxfordian)3
岩層: Sundance3
國家: 美國3
化石紀錄: The Paleobiology Database 收錄 1 筆3
發現: Wilbur Clinton Knight found and described the first fossils in 1895, near Ervay, Wyoming. He first called it Cimoliosaurus rex, then gave it its own genus name in 1898.1 2
仍有爭議: Scientists debate whether Megalneusaurus is a valid genus because many of the original fossils were lost.1