👉 An asterospondylous is a type of vertebrate in the class Chordata, which includes birds, fish, and mammals. It refers to an animal with a long, slender tail that is attached to the sides of its body by a series of ligaments and tendons. This tail is known as a "tailbone" or "pelvis," and it provides support for the animal's overall structure and helps to prevent it from moving too much in one direction. The term "