Despite its common name, the king brown snake is not a true brown snake but one of the black snake family. A bite from this snake would therefore be treated with black snake antivenom. As with many Australian snakes the colour is variable. Most specimens are mid-brown, some with a coppery tinge, others being quite dark. Often each individual scale has a dark area and a light area giving the snake a subtle pattern. King browns are robust snakes with a wide head and large specimens will reach a length over 2.5m.
A widespread species inhabiting all of Australia except the east and south coastal areas. As its alternative name suggests, it inhabits mulga country but is certainly not restricted to this habitat. Almost any type of environment is used except for rainforests, including grasslands, heath, true desert and open woodland.
The king brown snake has specialized in eating other reptiles. Lizards and snakes, including other king browns are preferred but occasionally birds, mammals and frogs are also consumed.
Female king browns produce a clutch of around 8-20 eggs, which may be laid in a disused burrow or beneath a log or rock. There is no maternal care for the eggs once they have been laid. Incubation lasts for about 2-3 months after which time the baby snakes go in search of their first lizard meal.