A Brumby or broom-tail
The name of this type of horse is called a 'Brumby'.
Brumbies
Simple : They are all mustangs. (a mustang : A name given to all wild horses but is actually a breed of its own)
The wild but rare Equus horse can be found in the grassland of Australia.
Wild horse (Mustang) groups are called bands in the US, or sometimes a herd of mustangs. In Australia they would be called a herd or mob of brumbies and the same would go for New Zealand or kaimanawa wild horses.
I don't approve of the name 'feral' but another name is Brumby, the wild horses of Australia.
The only true wild horse is the Przewalski's horse.
Wild Horse
Prewalski's horse.
MONGOLIA also known as the Asian Wild Horse or Mongolian Wild Horse, or Takhi
Wild horses are called different things all over the world. In America they are sometimes called mustangs. In Australia they are called a brumby. Another name is cayuse.