Horse outward similarity is an unreliable measure of relatedness. Besides the horse, there are six other species of genus "Equus" in the Equidae family. These are the ass or donkey, "Equus asinus"; the mountain zebra, "Equus zebra"; plains zebra, "Equus quagga"; Grévy's zebra, "Equus grevyi"; the kiang, "Equus kiang"; and the onager, "Equus hemionus". Horses can crossbreed with other members of their genus. The most common hybrid is the mule, a cross between a "jack" (male donkey) and a mare. A related hybrid, a hinny, is a cross between a stallion and a jenny (female donkey). Other hybrids include the zorse,
Equus (comics) completely disappeared from the face of the Earth (including his wife, Lois Lane), is traced to an unspecified country in the Middle East. Investigating, Superman intervenes in a civil war by using his speed to snatch all the guns from a group of men fighting one another. The fighting continues however, and in his continued quest to put an end to it, Superman confronts Equus, a large, monstrous, cybernetically enhanced humanoid creature whose claws are capable of piercing Superman's skin. General Nox, the leader of the rebels, puts an end to the fight between the two beings, telling Superman that