恐龍卡第 1930 張，共 2 027 張

Xenodens

名字的意思： “strange tooth”1

吃：肉滄龍類白堊紀晚期嚴格來說不是恐龍

Xenodens was a mosasaur, a giant marine lizard that lived in the sea during the time of dinosaurs. It had a mouth full of flat, blade-like teeth that worked like a saw, just like a shark or a piranha. This helped it slice through fish, squid, and even other sea creatures.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

Ouled Abdoun Basin, Morocco1 2

長度

0.9 到 1.1 m (3 到 3.6 ft)1

最高速度

時速約 13 公里（8 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 2 隻家貓從鼻子接到尾巴一樣長跟 6 根香蕉頭尾相接一樣長能在 14 秒內游完一座大泳池（50 公尺）

Xenodens 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)

Xenodens 時速約 13 公里 (8 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

Xenodens means 'strange tooth' in Greek and Latin, and its species name calminechari means 'like a saw' in Arabic.1

Its teeth were short, flattened, and blade-like, forming a saw-like edge along the jaw. No other land or sea reptile had teeth like this.1

Xenodens lived about 72 to 66 million years ago, near the end of the Age of Dinosaurs.2

Scientists first described Xenodens in 2021 from two upper jaw bones found in a phosphate mine in Morocco.1

Some scientists thought the fossil might be a fake, but CT scans in 2025 showed the teeth were real and naturally attached.1

Xenodens was small for a mosasaur, only about 1 meter (3.3 feet) long. Many other mosasaurs were much bigger.1

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

?Was Xenodens a dinosaur?

No, Xenodens was a mosasaur, a marine lizard that lived in the sea during the time of dinosaurs.1

?How big was Xenodens?

About 1 meter (3.3 feet) long, which is small for a mosasaur.1

?What did Xenodens eat?

It likely ate fish, squid, crustaceans, and scavenged dead marine reptiles, using its saw-like teeth to slice through food.1

?Why did Xenodens have strange teeth?

Its short, flattened, blade-like teeth formed a saw-like edge, similar to dogfish sharks and piranhas, for cutting prey.1

迷思破解王

迷思： Xenodens was a dinosaur.

真相： Xenodens was a mosasaur, a type of marine lizard that lived in the ocean. Mosasaurs are not dinosaurs.1

給恐龍專家

學名: Xenodens
命名者: Longrich et al. 20212
類群: 滄龍類
科 / 演化支: Mosasauridae2
分類: Mosasauroidea2
岩石的年代: 72 到 66 百萬年 (Maastrichtian)2
岩層: Couche III2
國家: 摩洛哥2
化石紀錄: The Paleobiology Database 收錄 1 筆2
發現: Xenodens was named in 2021 by Nick Longrich and colleagues based on a left upper jaw bone bought from a local farmer in Morocco. The fossil came from the Sidi Chennane phosphate mine.1
仍有爭議: Some scientists still debate whether Xenodens is a real species or a fake fossil, though CT scans support its authenticity.1