恐龍卡第 1492 張，共 2 027 張

Psephoderma

名字的意思： “pebbly skin”1

吃：肉海生爬蟲類三疊紀中期到三疊紀晚期嚴格來說不是恐龍

Psephoderma was a marine reptile that lived in the Late Triassic, about 210 million years ago. It had a flat skull and a shell made of two parts, like a turtle, and used its long snout to dig up shellfish from the seafloor.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

243 到 201 百萬年前4

三疊紀中期到三疊紀晚期

化石發現地

Italy, Austria, Israel, and England2 1

長度

1.8 m (5.9 ft)1 3

最高速度

時速約 11 公里（7 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 4 隻家貓從鼻子接到尾巴一樣長跟 10 根香蕉頭尾相接一樣長能在 16 秒內游完一座大泳池（50 公尺）

Psephoderma 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)

Psephoderma 時速約 11 公里 (7 mph)

騎腳踏車的小朋友 時速約 12 公里 (7 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

Psephoderma had a long tail, up to about 80 cm (31 inches), covered in bony scutes.1

Its shell was split into two pieces: one over the ribs and another over the pelvis.1

The largest known Psephoderma fossil is 180 cm (5.9 feet) long.3

Its skull had a narrow, straight snout with grooves that led to the nostrils.1

Psephoderma had no teeth at the front of its mouth, only four large crushing teeth on each side of the palate.1

It lived in shallow, oxygen-rich waters near tidal channels, where it fed on shellfish like Modiolus and Isognomon.3

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

?Was Psephoderma a dinosaur?

No, Psephoderma was not a dinosaur. It was a marine reptile called a placodont, which is a type of sauropterygian.1

?How big was Psephoderma?

Psephoderma grew up to 180 centimetres (5.9 feet) long, which is about as long as a bathtub.1

?What did Psephoderma eat?

Psephoderma ate shellfish like Modiolus and Isognomon. It used its long snout to dig them up and crushed them with its large, flat teeth.3

?Could Psephoderma swim?

Yes, Psephoderma could swim. Its shell was streamlined for swimming, and it used its paddle-like limbs to move through the water.3

給恐龍專家

學名: Psephoderma
命名者: von Meyer 18584
類群: 海生爬蟲類
科 / 演化支: Placochelyida4
分類: Placodontia > Sauropterygia4
岩石的年代: 243 到 201 百萬年 ()4
岩層: Calcare di Zu, Kössener Schichten, Zorzino Limestone4
國家: 義大利, 奧地利, 以色列, 英國4
化石紀錄: The Paleobiology Database 收錄 10 筆4
又名: Placochelyanus （舊名稱現在也算作同一種動物）4
發現: Psephoderma was named by German paleontologist Hermann von Meyer in 1858. Fossils have been found in the Alps and England.1 2
仍有爭議: Scientists are not sure if Psephoderma used its shell mainly for defense or for swimming, but some think it was shaped to help it glide through water.3