恐龍卡第 1158 張，共 2 027 張

Megapterygius

名字的意思： “large wing”1

吃：肉滄龍類白堊紀晚期嚴格來說不是恐龍

Megapterygius was a huge marine lizard that swam in the seas around Japan 72 million years ago. It had enormous flippers that were longer than its head, and scientists think it even had a dorsal fin like a shark!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

84 到 66 百萬年前4

白堊紀晚期

化石發現地

Wakayama Prefecture, Japan1

長度

6 m (20 ft)1

體重

150 kg 到 450 kg (331 到 992 lb)3

最高速度

時速約 38 公里（24 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 22 隻狗一樣重

跟 6 隻狗從鼻子接到尾巴一樣長跟 33 根香蕉頭尾相接一樣長跟 90 顆西瓜一樣重跟 24 個幼兒園小朋友一樣重跟 14 個小學生一樣重能在 4.7 秒內游完一座大泳池（50 公尺）

Megapterygius 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)

Megapterygius 時速約 38 公里 (24 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

Megapterygius had rear flippers that were even longer than its front flippers, a feature only seen in one other mosasaur, Tylosaurus.1

Its flippers were longer than its skull, which is unique among mosasaurs with paddle-like limbs.1

The shape of its backbone suggests it had a dorsal fin, like a dolphin or shark, which would have helped it turn quickly in the water.1 2

Its skull was slightly wide around the eye sockets, giving it binocular vision that helped it hunt prey. This is only the second mosasaur known to have this ability.1

The fossil was found in 2006 by Akihiro Misaki, who was actually looking for ammonite fossils when he spotted a vertebra.1 2

More than 100 shark teeth were found around the Megapterygius skeleton, suggesting that sharks scavenged its body after it died.1

Megapterygius is the most complete mosasaur skeleton ever found in Japan or the northwestern Pacific.2

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

?How big was Megapterygius?

Megapterygius was about 6 metres long, with a skull about 0.8 metres long. That is roughly the size of a large great white shark.1 2

?Did Megapterygius have a dorsal fin?

Scientists think it did. The shape of its backbone is like that of dolphins and porpoises, which have dorsal fins, and this would have helped it turn quickly in the water. It's the first mosasaur with evidence of a dorsal fin.1 2

?What did Megapterygius eat?

Scientists think it hunted large groups of small prey, like schools of fish. Its binocular vision and big flippers would have helped it catch them.1

?When did Megapterygius live?

Megapterygius lived about 72 million years ago, during the Late Cretaceous period, in the seas around Japan.1 2

給恐龍專家

學名: Megapterygius
命名者: Konishi et al. 20234
類群: 滄龍類
科 / 演化支: Mosasauridae4
分類: Mosasauroidea4
岩石的年代: 84 到 66 百萬年 (Campanian / Maastrichtian)4
岩層: Toyajo4
國家: 日本4
化石紀錄: The Paleobiology Database 收錄 1 筆4
發現: The fossil was discovered in 2006 by Akihiro Misaki in Wakayama Prefecture, Japan. It was named Megapterygius wakayamaensis by Takuya Konishi and colleagues in 2023.1 2
仍有爭議: Scientists are still debating how Megapterygius used its four large flippers and tail fin together for swimming, since no modern animal has a similar body shape.2