Donkey
Donkeys can interbreed with other members of the family Equidae, and are commonly interbred with horses. The hybrid between a jack and a mare is a mule, valued as a working and riding animal in many countries. Some large donkey breeds such as the Asino di Martina Franca, the Baudet de Poitou and the Mammoth Jack are raised only for mule production. The hybrid between a stallion and a jenny is a hinny, and is less common. Like other inter-species hybrids, mules and hinnies are usually sterile. Donkeys can also breed with zebras in which the offspring is called a zonkey (among other names).
Canadia (annelid)
There has been some debate as to the placement of "Canadia" within the Annelida phylum. Although it is commonly accepted to be within Annelida, it is uncertain how it relates to modern annelids. Most paleontologists agree that it belongs to the class Polychaeta due in part to the presence of Parapodium. It has been proposed to be a member of the order Phyllodocida along with "Wiwaxia", another organism from the Burgess Shale. Both were placed in a new superfamily called Canadiacea, and were thought to be of closer relationship to each other than to modern annelids. However, "Wiwaxia" is no longer believed to have been an annelid and there is currently dispute as to whether or not "Canadia" should be classified as belonging to anything more derived than Polychaeta.