There are some species of spiders that eat their mother. After the babies grow big enough to look after themselves, the mother dies and the young will eat the carcus of their mother. There are also Brazilian amphibian that almost resembles a worm that will eat their mother's skin that she has shed.
While there may be no mammals, there are insects that do. Also, there are spiders where the mother is eaten to provide for the recently hatched eggs at birth.
