恐龍卡第 0842 張，共 2 027 張

Hydrotherosaurus

名字的意思： “fisherman lizard”1

吃：肉蛇頸龍類白堊紀晚期嚴格來說不是恐龍

Hydrotherosaurus was a long-necked marine reptile that swam in the seas near California about 70 million years ago. It used its tiny head and super long neck to sneak up on fish and snap them up.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

72 到 66 百萬年前2

白堊紀晚期

化石發現地

Panoche Hills, Fresno County, California, USA1 2

長度

7.8 到 8.8 m (26 到 29 ft)1

體重

1.9 公噸 (4,200 lb)1

最高速度

時速約 25 公里（16 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 1.5 台汽車一樣重

跟 9 隻狗從鼻子接到尾巴一樣長跟 49 根香蕉頭尾相接一樣長跟 95 隻狗一樣重跟 380 顆西瓜一樣重跟 100 個幼兒園小朋友一樣重跟 59 個小學生一樣重跟 4 隻北極熊一樣重能在 7.2 秒內游完一座大泳池（50 公尺）

Hydrotherosaurus 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)

Hydrotherosaurus 時速約 25 公里 (16 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

Hydrotherosaurus had one of the longest necks compared to its body of any elasmosaur, with 60 vertebrae in its neck.1

Its head was very small, only about 33 centimetres (13 inches) long.1

The first bones were found by Frank C. Paiva on his own property in California in 1937.1

A nearly complete skeleton was dug up and put on display at the Golden Gate International Exposition in San Francisco.1

It weighed about 1.9 metric tons (2.1 short tons), as heavy as a small car.1

Hydrotherosaurus lived in the Late Cretaceous period, between about 72 and 66 million years ago.1 2

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

?How big was Hydrotherosaurus?

Hydrotherosaurus was about 7.8 to 8.8 metres long and weighed around 1.9 metric tons.1

?What did Hydrotherosaurus eat?

It was an active, fish-eating animal, using its long neck and small head to snap up fish.1 2

?When did Hydrotherosaurus live?

It lived during the Late Cretaceous period, about 72 to 66 million years ago.1

?Where was Hydrotherosaurus found?

Its fossils were found in California, USA, in the Moreno Formation of Fresno County.1 2

給恐龍專家

學名: Hydrotherosaurus
命名者: Welles 19432
類群: 蛇頸龍類
科 / 演化支: Elasmosauridae2
分類: Plesiosauria > Elasmosauridae > Sauropterygia2
岩石的年代: 72 到 66 百萬年 (Maastrichtian)2
岩層: Moreno2
國家: 美國2
化石紀錄: The Paleobiology Database 收錄 1 筆2
發現: The first fossils were found by Frank C. Paiva in the Panoche Hills of California in 1937. In 1943, paleontologist Samuel Paul Welles named the species Hydrotherosaurus alexandrae after Annie Montague Alexander.1
仍有爭議: Scientists are not sure exactly how Hydrotherosaurus used its extremely long neck while hunting.1