What types of ancient plants and animals are known to you?

Ginkgo bilobate.
In the wild, this plant grows only in eastern China. However, 200 million years ago, it was distributed all over the planet, especially in the Northern Hemisphere, in areas with a temperate climate and high humidity. In Siberia, the Jurassic and Early Cretaceous period there were so many plants of the Ginkgo class that their remains are found in most sediments of those periods. According to researchers, in the autumn of that time, the earth was literally covered with ginkgo leaves, like a carpet.
A small deer, or canchil, is not only the smallest (its height at the withers is not more than 25 centimeters, and its maximum weight is about 2.5 kilograms), but it is also the oldest artiodactyl species on Earth. These animals existed even 50 million years ago, just when the units of ancient ungulates began to form. Since that time, the canchil has not changed much and more than any other species resembles its ancient ancestors.
Mississippi Carapace.
Similar to an alligator fish, the Mississippi carapace is one of the oldest fish living on Earth today. In the Mesozoic era, its ancestors inhabited many water bodies. Today, the Mississippi carapace lives in the valley of the lower Mississippi River, as well as in some freshwater lakes in the United States.
Shield
These small freshwater crustaceans are considered the most ancient creatures living today on Earth. Representatives of this species have not changed much since the Triassic period. At that time, dinosaurs had just appeared. Today, these animals live on almost every continent except Antarctica. However, shield species of the Triops cancriformis species are most common in Eurasia.
The metasequoia is glyptostroboid.
These conifers were widespread throughout the Northern Hemisphere from Cretaceous to Neogene. However, today in the wild, metasequoia can be seen only in the central part of China, in the provinces of Hubei and Sichuan.