恐龍卡第 0643 張，共 2 027 張

Eurycleidus

名字的意思： “broad clavicle”1

吃：肉蛇頸龍類侏羅紀早期嚴格來說不是恐龍

Eurycleidus was a big, swimming reptile that lived in the sea during the Early Jurassic, about 200 million years ago. It was not a dinosaur, but a plesiosaur with a long body and strong flippers. It used its sharp, needle-like teeth to catch fish.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

201 到 184 百萬年前2

侏羅紀早期

化石發現地

Fossils were found in England, United Kingdom, especially in Somerset and possibly other places.1 2

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)

Eurycleidus 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

Eurycleidus had large shoulder bones, which gave it a powerful forward stroke for fast swimming.1

The first fossils were bought by Thomas Hawkins in the early 1830s from a quarry in Street, Somerset, England.1

In 1837, Richard Owen mistakenly thought the fossils came from Lyme Regis, but they actually came from Somerset.1

The species was first named Plesiosaurus arcuatus in 1840, and later renamed Eurycleidus in 1922.1

Some fossils that were once thought to be Eurycleidus were later moved to other genera, like Atychodracon and Lindwurmia.1

Eurycleidus lived in the sea and was an active swimmer, living near the surface.2

Eurycleidus 的 AI 繪圖 — 這是電腦根據科學家目前的知識，用 AI 畫出 Eurycleidus 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。

迷思破解王

迷思： Eurycleidus was a dinosaur.

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

給恐龍專家

學名: Eurycleidus
命名者: Andrews 19222
類群: 蛇頸龍類
科 / 演化支: Rhomaleosauridae2
分類: Plesiosauria > Sauropterygia2
岩石的年代: 201 到 184 百萬年 (Hettangian / Pliensbachian)2
岩層: Blue Lias2
國家: 英國2
化石紀錄: The Paleobiology Database 收錄 4 筆2
發現: The first fossils were collected by Thomas Hawkins in the early 1830s from a quarry in Street, Somerset, England. Richard Owen named the species Plesiosaurus arcuatus in 1840, and Charles William Andrews renamed it Eurycleidus in 1922.1
仍有爭議: Scientists still debate exactly which fossils belong to Eurycleidus, because some specimens were later moved to other genera.1