恐龍卡第 1723 張，共 2 027 張

Styxosaurus

名字的意思： “river of the dead lizard”1

吃：肉蛇頸龍類白堊紀晚期嚴格來說不是恐龍

Styxosaurus was a long-necked marine reptile that swam in the shallow seas that once covered North America. It was not a dinosaur, but a plesiosaur, and it used its sharp teeth to catch fish and squid.1 2

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

90 到 72 百萬年前5

白堊紀晚期

化石發現地

Kansas, South Dakota, Nebraska, and Wyoming, USA2

長度

5 到 7 m (16 到 23 ft)2

體重

3.1 公噸 (6,800 lb)3

最高速度

時速約 24 公里（15 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？

牠有多重？

跟 2 台汽車一樣重

跟 7 隻狗從鼻子接到尾巴一樣長跟 39 根香蕉頭尾相接一樣長跟 160 隻狗一樣重跟 620 顆西瓜一樣重跟 4 整班小學生一樣重跟 7 隻北極熊一樣重能在 7.5 秒內游完一座大泳池（50 公尺）

Styxosaurus 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)

Styxosaurus 時速約 24 公里 (15 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

Styxosaurus had an extremely long neck, with over 60 vertebrae, making it one of the longest necks of any animal that ever lived.2

It lived in the Western Interior Seaway, a huge inland sea that split North America in two during the time of the dinosaurs.2

Some fossils of Styxosaurus were once thought to belong to a different animal called Hydralmosaurus, but scientists now think they are the same.2

Styxosaurus 的 AI 繪圖 — 這是電腦根據科學家目前的知識，用 AI 畫出 Styxosaurus 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 Styxosaurus 最常被問的問題

?How big was Styxosaurus?

About 11.3 metres (37 ft) long and weighed around 3.1 metric tons (3.4 short tons). Its neck alone was about 5.25 metres (17.2 ft) long.4

?What did Styxosaurus eat?

It ate fish, squid, and belemnites. It grabbed slippery prey with its sharp, interlocking teeth and swallowed it whole.4

?When did Styxosaurus live?

It lived during the Late Cretaceous period, about 100 to 72 million years ago.4 5

?Did Styxosaurus have a long neck?

Yes, it had an extremely long neck with over 60 vertebrae, making it one of the longest necks of any animal.4 2

?Is Styxosaurus a dinosaur?

No, it is a plesiosaur, a marine reptile that lived in the sea, not a dinosaur.4

?Where was Styxosaurus found?

Fossils have been found in North America, mainly in Kansas, South Dakota, Nebraska, and Wyoming, in rocks that were once the bottom of a shallow sea.4 5

給恐龍專家

學名: Styxosaurus
命名者: Welles 19435
類群: 蛇頸龍類
科 / 演化支: Elasmosauridae5
分類: Plesiosauria > Elasmosauridae > Sauropterygia5
岩石的年代: 90 到 72 百萬年 (Coniacian / Campanian)5
岩層: Pierre Shale, Niobrara5
國家: 美國5
化石紀錄: The Paleobiology Database 收錄 8 筆5
又名: Hydralmosaurus （舊名稱現在也算作同一種動物）5
仍有爭議: Scientists are still debating exactly how many species of Styxosaurus existed, and whether some fossils belong to this genus or to other elasmosaurids.2