恐龍卡第 1552 張，共 2 027 張

Rikisaurus

名字的意思： “Riki's lizard”3

吃：肉滄龍類白堊紀晚期嚴格來說不是恐龍

Rikisaurus was a marine lizard that swam in the warm seas near New Zealand about 80 million years ago. It was a mosasaur, a relative of today's monitor lizards, but with flippers instead of legs. This predator hunted fish and other sea creatures with its long, pointed snout and many small teeth.3 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

84 到 66 百萬年前3

白堊紀晚期

化石發現地

Mangahouanga Stream, Hawke's Bay, North Island, New Zealand3 1

長度

2 到 3 m (6.6 到 9.8 ft)1

最高速度

時速約 33 公里（21 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 5.5 秒內游完一座大泳池（50 公尺）

Rikisaurus 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)

Rikisaurus 時速約 33 公里 (21 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

Rikisaurus had a very long, slender snout that tapered to a point, and its upper jaw had 13 or 14 teeth on each side.1

Its teeth were small, with two ridges (bicarinate), and the enamel was smooth.1

The lower jaw had 15 or 16 teeth and deepened in the middle, giving it a semicircular bump (coronoid).1

Rikisaurus is known from only one fossil: a skull and four neck bones found in New Zealand.1

It lived between 83.6 and 66 million years ago, during the Campanian and Maastrichtian ages of the Late Cretaceous.1

Scientists think Rikisaurus was a small adult mosasaur, about the size of a modern dolphin.1

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

?Is Rikisaurus a dinosaur?

No, it is a mosasaur, a marine reptile related to today's monitor lizards, not a dinosaur.2 3

?How big was Rikisaurus?

It was a small adult mosasaur, about the size of a modern dolphin, though exact length is not given in the sources.3

?What did Rikisaurus eat?

It was a carnivore that hunted fish and other sea creatures with its long, pointed snout and many small teeth.3

?Where was Rikisaurus found?

Its only known fossil, a skull and four neck bones, was found in the Mangahouanga Stream in New Zealand.3

給恐龍專家

學名: Rikisaurus
命名者: Wiffen 19903
類群: 滄龍類
科 / 演化支: Mosasauridae3
分類: Mosasauroidea3
岩石的年代: 84 到 66 百萬年 (Campanian / Maastrichtian)3
岩層: Tahora3
國家: 紐西蘭3
化石紀錄: The Paleobiology Database 收錄 1 筆3
發現: Rikisaurus was named by paleontologist J. Wiffen in 1990, based on a skull and neck bones found in the Tahora Formation of New Zealand.3 1
仍有爭議: Scientists are not sure exactly how big Rikisaurus grew, because only one skull has been found.1