What's the difference between a dragon turtle and a snake turtle in ancient legends?

The snake turtle is a real animal, the dragon turtle is a legendary auspicious beast, and Xuanwu is among the four beasts.

Snake turtle, also known as snake-necked turtle, is a family of ancient turtles. Its shell is round or heart-shaped. Its shell is very thick, and there is no middle throat shield or lower edge shield in its abdomen. It lived from the late Jurassic to the early Cretaceous. Mainly distributed in Europe, Asia and China and Sichuan. Snake-necked turtles and Tianfu turtles all belong to this category.

Dragon turtle, an auspicious beast, is lucky and turns into three evil spirits. Dragon turtle can promote wealth when it is placed in a financial position, and it is most effective when it is placed in a three-evil position or a place with heavy water vapor. There is a saying in Feng Shui: "Get rich quickly, and three evils compete." The position of feng shui with heavy moisture is dominated by right and wrong, and the dragon turtle can change its mouth shape and strengthen its popularity. Dragon turtle is a symbol of patience, bearing, longevity and authority. Among many auspicious things, this beast is the most auspicious one.