恐龍卡第 1555 張，共 2 027 張

Riojasaurus

名字的意思： “lizard from La Rioja”1

吃：植物長脖子恐龍三疊紀晚期

Riojasaurus was a huge, plant-eating dinosaur with a long neck and a heavy body. It lived during the Late Triassic period in what is now Argentina. It probably walked slowly on all four legs, munching on leaves with its leaf-shaped teeth.1

生存年代

227 到 206 百萬年前4

三疊紀晚期

化石發現地

La Rioja Province, Argentina (Los Colorados Formation)1 2

長度

6.6 到 10 m (22 到 33 ft)1

體重

800 kg 到 3 公噸 (1,800 到 6,600 lb)1

高度

5 m (16 ft)3

最高速度

時速約 26 公里（16 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 2 台汽車一樣重

跟 2 台汽車排成一排一樣長跟 56 根香蕉頭尾相接一樣長跟 150 隻狗一樣重跟 600 顆西瓜一樣重跟 4 整班小學生一樣重跟 7 隻北極熊一樣重高到能從 2 樓的窗戶往裡看能在 14 秒內跑完 100 公尺（最快的人類要 9.6 秒）

Riojasaurus 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)

Riojasaurus 時速約 26 公里 (16 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

Riojasaurus had very dense and massive leg bones, making it heavy and sturdy for an early sauropodomorph.1

Unlike most early relatives, Riojasaurus had four sacral vertebrae in its hip area instead of three, which helped support its weight.1

Its neck bones were longer than those of other sauropodomorphs found in the same formation, making its neck especially long.1

The first Riojasaurus skeleton found had no skull. A well-preserved skull was later discovered in 1987 and described in 1995.1

Some scientists think Riojasaurus may have been active at short intervals throughout the day and night, based on the shape of its eye bones (scleral rings).1

Riojasaurus is the only known riojasaurid dinosaur from South America, and it may be closely related to Melanorosaurus from southern Africa.1

Its front and hind limbs were nearly the same length, which is a clue that it walked on all fours and could not rear up on its back legs.1

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

?How big was Riojasaurus?

Riojasaurus was about 6.6 metres (21.7 feet) long and weighed around 800 kilograms (1,764 pounds). Some large individuals may have reached 10 metres (32.8 feet) long and weighed 3 metric tons (3.3 short tons).1

?What did Riojasaurus eat?

Riojasaurus was a herbivore that ate plants. Its leaf-shaped, serrated teeth were used for grazing on soft vegetation like gymnosperms, and it may have swallowed stones (gastroliths) to help grind food in its stomach.1 3

?Could Riojasaurus walk on two legs?

No, Riojasaurus probably walked on all four legs. Its front and hind limbs were nearly the same length, and its leg bones were dense and massive, suggesting it moved slowly on all fours and could not rear up on its back legs.1

?When did Riojasaurus live?

Riojasaurus lived during the Late Triassic Period, about 225 to 213 million years ago. Its fossils have been found in the Los Colorados Formation in Argentina.1

?Is Riojasaurus a dinosaur?

Yes, Riojasaurus is a dinosaur. It is a herbivorous sauropodomorph dinosaur from the Late Triassic of Argentina.1

?Did Riojasaurus have feathers?

No, there is no evidence that Riojasaurus had feathers. Its fossils show only scales and bones, and it is not known to have any feather-like structures.1

給恐龍專家

學名: Riojasaurus
命名者: Bonaparte 19694
類群: 長脖子恐龍
科 / 演化支: Riojasauridae4
分類: Sauropodomorpha4
岩石的年代: 227 到 206 百萬年 (Norian)4
岩層: Los Colorados4
國家: 阿根廷4
化石紀錄: The Paleobiology Database 收錄 2 筆4
又名: Strenusaurus （舊名稱現在也算作同一種動物）4
發現: Riojasaurus was named by Argentine paleontologist José Bonaparte in 1969. The first skeleton (holotype PVL 3808) was found in 1966 in the Los Colorados Formation of La Rioja, Argentina. Later, many more skeletons and a skull were discovered.1 4
仍有爭議: Scientists disagree on whether Riojasaurus was completely quadrupedal or could sometimes walk on two legs. The hand and shoulder bones suggest it might have been able to move in different ways.1