恐龍卡第 1137 張，共 2 027 張

Marambionectes

名字的意思： “Marambio Island swimmer”1

吃：肉蛇頸龍類白堊紀晚期嚴格來說不是恐龍

Marambionectes was a long-necked marine reptile that swam in the seas near Antarctica about 70 million years ago. It was not a dinosaur, but a fierce hunter that used its flippers to glide through the water.1 3

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3

白堊紀晚期

化石發現地

Antarctica, on Marambio (Seymour) Island in the López de Bertodano Formation1 3

最高速度

時速約 27 公里（17 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)

Marambionectes 時速約 27 公里 (17 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

Marambionectes had 48 neck vertebrae, and the 5th to 29th of these had special side keels, a feature not seen in other elasmosaurids.2

Its lower jaw had three tooth sockets at the front and a wide groove, which helped scientists link it to a group called aristonectines.2

The fossil skeleton was found in 2018 and includes parts of the skull, many vertebrae, ribs, and limb bones, all from an adult animal.1

Scientists think Marambionectes was closely related to the aristonectines, a group of elasmosaurids with short necks and big heads.1 2

The name honors Omar J. Molina, an Argentinian fossil preparator who worked in Antarctica.1

Marambionectes 的 AI 繪圖 — 這是電腦根據科學家目前的知識，用 AI 畫出 Marambionectes 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。

迷思破解王

迷思： Some people think all plesiosaurs were dinosaurs.

真相： Plesiosaurs like Marambionectes were marine reptiles, not dinosaurs. Dinosaurs lived on land and had different body features.1

給恐龍專家

學名: Marambionectes
命名者: O’Gorman et al. 20243
類群: 蛇頸龍類
科 / 演化支: Elasmosauridae3
分類: Plesiosauria > Elasmosauridae > Sauropterygia3
岩石的年代: 72 到 66 百萬年 (Maastrichtian)3
岩層: López de Bertodano3
國家: 南極洲3
化石紀錄: The Paleobiology Database 收錄 1 筆3
發現: The fossil was found in 2018 on Marambio Island, Antarctica, and was named by O'Gorman and colleagues in 2024.1 3
仍有爭議: Scientists are still debating exactly how Marambionectes is related to other elasmosaurids, especially whether it belongs inside or just outside the aristonectine group.1 2