Subclass Pantotheria refers to a group of extinct mammals that lived during the Mesozoic era. There are various synonyms for this term, which may be used interchangeably in scientific literature. Some of the common synonyms include Eupantotheria, Paratheria, and Triconodonta. These terms refer to the same group of mammals but may be used by different researchers based on their preferred nomenclature. The Pantotheria subclass is known for its small size and diverse diet, which included insects, plants, and small mammals. The fossils of these animals have been found in various parts of the world, providing researchers with insights into the evolution of mammals.