Didelphoidea

Didelphoidea is an infraorder of mammals that comprises the opossums and their relatives. This group is part of the order Marsupialia and is native to the Americas. The name Didelphoidea comes from the scientific name of the mouse opossum, Didelphimorphia.

The infraorder Didelphoidea includes several families of opossums, such as the Didelphidae, which are the most diverse and widespread group within Didelphoidea. Other families in the infraorder include the Didelphimorphia and the Gracilininae. These groups are primarily found in the Americas, with some species present in Central America and a few in Mexico.

Members of the infraorder Didelphoidea are relatively small mammals, with body lengths ranging from about 20 to 100 centimeters, and weighing between 0.05 and 10 kilograms. Most opossums have a prehensile tail, which they use for climbing and grasping onto branches. The reproductive habits of opossums are also distinct, as females are able to conceive while still nursing their young from a previous pregnancy. This means that females can be pregnant and lactating at the same time, a process known as "embryonic diapause."

Throughout their geographical range, members of the infraorder Didelphoidea are commonly found in a variety of different habitats, including forests, grasslands, and deserts. Their diet consists mainly of invertebrates, fruits, and other small animals. Despite their widespread distribution and small size, opossums are not well-studied, and often remain unknown or misunderstood by many people.