The nominal race of Slaty-headed Parakeet (above) is native to the western foothills of the Himalayas (India, Pakistan, Afghanistan south Tibet).
It is one of the Ring-necked species of parakeets and one of the few parrots to undertake seasonal migration (lower down mountain in winter, higher in summer).
The subspecies or related species Finsch's Slaty-headed (below), also called Finsch's or Grey-headed Parakeet (Psittacula himalayana finschi or P. finschi), inhabits southeast Asia.
Both have the slate-grey head after which they are named and the male has a narrow black border with a blue-green nape. The long tail has blue feathers with yellow tips (more violet-blue in the smaller Finsch's subspecies which is also a slightly lighter, yellower green body/wings) and both male and female have a red upper beak fading to orange and an orange lower beak.
Finsch's Slaty-headed or the Grey-headed Parakeet (Psittacula himalayana finschi or Psittacula finschi)
Superficially similar to the Slaty-headed Parakeet, the Emerald-collared Parakeet, also known as Layard's Parakeet, is native to Sri Lanka.
Both male and female have a slate-grey head with a thin black border widening to a black chinstrap and an emerald green nape. The long blue tail is tipped with yellow.
The back and wings are grey with green. The male (above left) has a red upper beak and brown lower beak and the female (above right) has an all black beak.