Mesosaurus - Mesosaurus (English spelling)

A fossil reptile that lived in South and South America from about 299 to 270.6 million years ago during the early Permian period of the Paleozoic Era. It was about 60 centimeters long. It was carnivorous, with five fingers on each of its front and back legs, which were connected by webbed feet. Its long jaws were equipped with sharp rows of teeth, which were useful for catching small fish and shrimp. It had a long body behind a relatively long neck, and its tail was long and flat, rising high above and below. Its tail was also easily bent, and it appears to have had fins on the top and bottom along its entire length, resembling the tail of a swimming animal. Its shape was adapted to life in freshwater rivers and swamps, and its form, habits, and the distribution of fossils are considered one piece of evidence that the two continents were connected at that time.

[Ikuo Obata]

"The Torn Continent" by Ikuo Obata and Hide Kato (Kaiseisha Bunko)

Source: Shogakukan Encyclopedia Nipponica About Encyclopedia Nipponica Information | Legend

古生代ペルム紀（二畳紀）前期の、約2億9900万年～2億7060万年前に南アフリカと南アメリカにいた化石爬虫類(はちゅうるい)。全長約60センチメートル。肉食で、前・後肢にそれぞれ5本の指をもち、それらは水かきでつながっていた。長いあごには鋭い歯列を備え、小魚や小さなエビなどをとらえるのに便利であった。比較的長い頸(くび)の後ろに長い胴をもち、尾も長く平たく、上下に高くなっていた。また尾は屈曲しやすく、全長にわたり上下にひれがついていたらしく、泳ぐ動物の尾に似る。淡水の川や沼の生活に適応した形を示しており、その形態や習性および化石の産状分布から、当時両大陸がつながっていた証拠の一つに数えられている。

［小畠郁生］

『小畠郁生・加藤秀著『ひきさかれた大陸』（偕成社文庫）』

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