Adult Male:
The entire head is grey, excluding the feathers below the lower mandible, chin, and throat, which are pale black. A vibrant, light green collar is present at the nape of the neck. The dorsal surface is a slightly yellowish green. The wings are green, with a red marking near the wing joint. The primary feathers are pale black with a hint of green along the outer vane and a yellow edge on the inner vane. The central tail feathers are long and blue, with yellow tips. The outer tail feathers are green on the outer vane and yellow on the inner vane. The ventral surface is yellow-green.
Adult Female:
Similar to the male, but lacks the red marking on the wings.
Juvenile:
Resembles the female, but the head exhibits less grey and more green coloration. The eyes are white or pale yellow. The upper mandible is bright red, while the lower mandible is yellow. The legs are dull green.
Measurements:
- Wing: 138 – 157 mm
- Tail: 185 – 299 mm
- Tarsus (Leg): 13 – 14 mm
- Bill: 21 – 22 mm
Distribution:
The Grey-headed Parakeet is found in Assam, Burma (Myanmar), Thailand, and Indochina.
Vietnam: This species is present in Bắc Thái, Hòa Bình, Lai Châu, Quảng Trị, and Thừa Thiên provinces.