恐龍卡第 1460 張，共 2 027 張

Polycotylus

名字的意思： “much-cupped vertebrae”1

吃：肉蛇頸龍類侏羅紀晚期到白堊紀晚期嚴格來說不是恐龍

Polycotylus was a short-necked plesiosaur that swam in the warm seas of North America and Europe during the Cretaceous. It had a big head, strong flippers, and gave birth to live babies in the water, just like whales do today.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

152 到 72 百萬年前3

侏羅紀晚期到白堊紀晚期

化石發現地

Kansas, South Dakota, Alabama, and Wyoming in the USA; also France and Russia1 2

長度

4.7 到 5.4 m (15 到 18 ft)1

體重

1 公噸 (2,200 lb)1

最高速度

時速約 27 公里（17 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 50 隻狗一樣重

跟 5 隻狗從鼻子接到尾巴一樣長跟 30 根香蕉頭尾相接一樣長跟 200 顆西瓜一樣重跟 53 個幼兒園小朋友一樣重跟 31 個小學生一樣重跟 2 隻北極熊一樣重能在 6.7 秒內游完一座大泳池（50 公尺）

Polycotylus 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)

Polycotylus 時速約 27 公里 (17 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

Polycotylus was named by famous paleontologist Edward Drinker Cope in 1869 from fossils found in Kansas.1

A fossil of Polycotylus found in Kansas contains a single large fetus inside the mother, proving that these plesiosaurs gave live birth.1

The baby Polycotylus was about 1.5 metres (4.9 feet) long, which is about 32 percent of the mother's length.1

Polycotylus had a short neck and a long head, making it look a bit like a pliosaur, but it is actually a type of plesiosaur called a polycotylid.1

Its name means 'much-cupped vertebrae' because the bones in its spine have deep cup-like hollows.1

Polycotylus lived in the Western Interior Seaway, a shallow sea that split North America in two during the Cretaceous.1

Scientists think Polycotylus gave birth to just one large baby at a time, a strategy called K-selection.1

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

?How big was Polycotylus?

Polycotylus was a medium-sized plesiosaur, measuring about 4.7 to 5.4 metres (15 to 18 feet) long and weighing over 1 metric ton (1.1 short tons).1

?Did Polycotylus have a short neck?

Yes, Polycotylus had a short neck and a long head, unlike the long-necked plesiosaurs like Elasmosaurus.1

?What did Polycotylus eat?

Polycotylus had thick teeth with striations on their surfaces, which suggests it ate fish and other marine animals, but the sources do not give a specific diet.1

?When did Polycotylus live?

Polycotylus lived toward the end of the Cretaceous period, about 84 to 66 million years ago.1

迷思破解王

迷思： Many people think all plesiosaurs had long necks like the Loch Ness Monster.

真相： Polycotylus had a short neck and a large head, very different from long-necked plesiosaurs like Elasmosaurus.1

給恐龍專家

學名: Polycotylus
命名者: Cope 18693
類群: 蛇頸龍類
科 / 演化支: Polycotylidae3
分類: Plesiosauria > Sauropterygia3
岩石的年代: 152 到 72 百萬年 (Kimmeridgian / Campanian)3
岩層: Niobrara, Frontier, Mooreville Chalk3
國家: 美國, 法國, 俄羅斯3
化石紀錄: The Paleobiology Database 收錄 10 筆3
發現: Edward Drinker Cope named Polycotylus in 1869 from fragmentary bones found in the Niobrara Formation of Kansas. A nearly complete skeleton was later found in Alabama in 1949 but not described until 2002.1
仍有爭議: Scientists are not sure exactly how many species of Polycotylus existed, and some species may be the same as others.1