恐龍卡第 1551 張，共 2 027 張

Richardoestesia

名字的意思： “Richard Estes' lizard”1

吃：肉迅猛龍類侏羅紀晚期到白堊紀晚期

Richardoestesia is known only from its teeth, which are long, slender, and curved. These teeth tell us it was a meat-eating dinosaur that hunted small animals like lizards and mammals.1

生存年代

155 到 66 百萬年前5

侏羅紀晚期到白堊紀晚期

化石發現地

Alberta, Canada; many states in the USA (including Montana, Wyoming, Texas); also Spain, France, Romania, Uzbekistan, and Mexico5

長度

2 到 3.3 m (6.6 到 11 ft)2 3

體重

50 kg 到 63 kg (110 到 139 lb)2 3

高度

0.7 m (2.3 ft)2

最高速度

時速約 50 公里（31 英里）

跑步, 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？

牠有多高？

牠有多重？

跟 3 隻狗一樣重

跟 3 隻狗從鼻子接到尾巴一樣長跟 18 根香蕉頭尾相接一樣長跟 13 顆西瓜一樣重跟 3 個幼兒園小朋友一樣重跟 2 個小學生一樣重能在 7.2 秒內跑完 100 公尺（最快的人類要 9.6 秒）

Richardoestesia 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)

Richardoestesia 時速約 50 公里 (31 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

Richardoestesia is known only from its teeth, not from whole skeletons. Scientists call it a 'form taxon' because they group similar-looking teeth together.1

The teeth of Richardoestesia are very long and slender compared to other meat-eating dinosaurs. They look like thin blades.1

If all the teeth assigned to Richardoestesia really belong to the same kind of dinosaur, it would have lived for over 80 million years, from the Late Jurassic to the end of the Cretaceous.1

Richardoestesia teeth have been found all over the world, including North America, Europe, and Asia. That would make it one of the most widespread dinosaurs ever.1

The name Richardoestesia honors paleontologist Richard Estes, who studied small fossils and dinosaur teeth.1

Some scientists think Richardoestesia might have been a dromaeosaur (a raptor) or a troodontid, but nobody knows for sure because no body fossils have been found.5

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

?What did Richardoestesia eat?

Richardoestesia was a meat-eating dinosaur, and some studies think it may have eaten fish because its teeth are often found in marine sites. Its long, slender teeth were good for catching small animals like lizards and mammals.1 4

?How big was Richardoestesia?

Nobody knows for sure because only its teeth have been found. One estimate from a tooth in Wyoming suggests it weighed about 100 kilograms (220 pounds), but scientists are not certain.4

?When did Richardoestesia live?

Richardoestesia lived during the Late Cretaceous, about 76.5 to 75 million years ago, based on teeth from the Dinosaur Park Formation. Some similar teeth are much older, from the Late Jurassic, but those may belong to different dinosaurs.1

?Was Richardoestesia a dinosaur?

Yes, Richardoestesia was a theropod dinosaur, a meat-eater related to raptors and other bird-like dinosaurs. It is known only from its teeth, not from a full skeleton.1

?Why is Richardoestesia known only from teeth?

Scientists have only found Richardoestesia's teeth, not its body fossils. That is why it is called a 'form taxon', because they group similar-looking teeth together without knowing the whole animal.1

?Could Richardoestesia swim?

Some scientists think Richardoestesia might have eaten fish because its teeth are often found in marine rocks, but nobody knows if it could swim. It was probably a land dinosaur that sometimes hunted near water.1

迷思破解王

迷思： Richardoestesia is a well-known dinosaur with a complete skeleton.

真相： Richardoestesia is only known from isolated teeth. No complete skeleton has ever been found, so scientists are not sure what it looked like.1

給恐龍專家

學名: Richardoestesia
命名者: Currie et al. 19905
類群: 迅猛龍類
科 / 演化支: Dromaeosauridae5
分類: Theropoda > Dromaeosauridae5
岩石的年代: 155 到 66 百萬年 (Kimmeridgian / Maastrichtian)5
岩層: Hell Creek, Milk River, Dinosaur Park5
國家: 美國, 加拿大, 西班牙, 烏茲別克, 羅馬尼亞, 墨西哥5
化石紀錄: The Paleobiology Database 收錄 239 筆5
發現: The first Richardoestesia fossils were jaws found in 1917 by Charles Hazelius Sternberg and his sons in Dinosaur Provincial Park, Alberta, Canada. The name was given in 1990 by paleontologist Philip Currie and colleagues.1
仍有爭議: Scientists are not sure if all the teeth called Richardoestesia really belong to the same dinosaur. Many may come from different species that have not been named yet.1