恐龍卡第 0012 張，共 2 027 張

Acamptonectes

名字的意思： “stiff swimmer”1

吃：肉魚龍類白堊紀早期嚴格來說不是恐龍

Acamptonectes was a fast-swimming marine reptile that lived in the Early Cretaceous seas. It had a stiff body and large eyes, perfect for hunting fish and squid in the deep ocean.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

133 到 126 百萬年前3

白堊紀早期

化石發現地

England (Speeton Clay Formation) and Germany1 3

長度

3 m (9.8 ft)1

最高速度

時速約 48 公里（30 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 3 隻狗從鼻子接到尾巴一樣長跟 17 根香蕉頭尾相接一樣長能在 3.8 秒內游完一座大泳池（50 公尺）

Acamptonectes 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)

Acamptonectes 時速約 48 公里 (30 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

Acamptonectes belongs to a group called ophthalmosaurids, which had very large eyes for seeing in dark, deep water.1 2

Its name means 'stiff swimmer' because its body was unusually rigid, helping it move fast through the water.1

Acamptonectes lived about 133 to 129 million years ago, during the Hauterivian stage of the Early Cretaceous.1

Scientists once thought most ichthyosaurs died out at the end of the Jurassic, but Acamptonectes shows they survived and thrived into the Cretaceous.2 1

The first Acamptonectes fossil was found in 1958 by geology students near Speeton, England, but it was not named until 2012.2 1

Its teeth had tiny ridges along the length, which helped it grip slippery prey like fish and squid.1

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

?Was Acamptonectes a dinosaur?

No, it was a marine reptile called an ichthyosaur, not a dinosaur.1

?How big was Acamptonectes?

It was about 3 metres (9.8 feet) long.1

?What did Acamptonectes eat?

It likely ate soft, fleshy prey like fish and squid, using its slender ridged teeth to impale them.1

?Why did Acamptonectes have a stiff body?

Its stiff body helped it swim fast like a tuna by making it more streamlined in the water.1

迷思破解王

迷思： Many people think all ichthyosaurs went extinct at the end of the Jurassic.

真相： Acamptonectes and other ophthalmosaurids lived well into the Cretaceous, showing no mass extinction at that time.2 1

給恐龍專家

學名: Acamptonectes
命名者: Fischer et al. 20123
類群: 魚龍類
科 / 演化支: Ophthalmosauridae3
分類: Ichthyosauria > Ichthyosauromorpha3
岩石的年代: 133 到 126 百萬年 (Hauterivian)3
岩層: Speeton Clay3
國家: 英國, 德國3
化石紀錄: The Paleobiology Database 收錄 3 筆3
發現: Acamptonectes was named in 2012 by a team of scientists including V. Fischer, M. W. Maisch, and D. Naish. The first specimen was collected in 1958 by geology students in Speeton, England, but it took decades to study and describe.2 3
仍有爭議: Scientists are still debating whether Acamptonectes had a different diet or lifestyle from other Cretaceous ichthyosaurs because of its unusual shallow snout and tooth shape.1