A good gauge of a male lion’s age is the darkness of his mane. The darker the mane, the older the lion.
In 2017 the Cat Classification Task Force reduced the number of valid lion subspecies to two: the Northern Lion & the Southern Lion.
When lions breed with tigers the resulting hybrids are known as ligers and tigons. There are also lion and leopard hybrids known as leopons and lion and jaguar hybrids known as jaglions.