Update 
Hello & welcome to my obsession 
The Big Nine
Lovebirds come in 9 species and are broken into three groups: The white-eye ring group, the intermediate group, and the sexually dimorphic group. Within these groups are many different colors and types of lovebirds.
The white-eye ring group consists of Masked lovebirds, Fischer's lovebirds, Black-Cheeked lovebirds, and Nyasa lovebirds.
The Masked lovebirds (Agapornis personata personata) have a blackish brown head, the chest and lower neck are yellow and the beak is red. They have a green body with a bluish rump and they are about 6- 6 1/4 inches (15-15.7cm).
Mask
Fischer's Lovebirds (Agapornis personata fischeri) have an orange forehead, cheeks and throat, with a red beak, green body, and blue rump. The beak is red and they are 4 inches (10cm) long.
Fischer's
Black Cheeked lovebirds (Agapornis personata nigrigens) have an overall colour of green, with brown/black cheeks and forehead. The back of the head is yellow/green, and the throat is orange. They have a red beak and these birds are 4 1/2 inches (11cm).
Black Cheek
Nyasa lovebirds (Agapornis personata lilianae) are mainly green birds with a red beak, red forehead, and an orange/red throat and cheeks. The beak is red and these birds are 4 1/4 inches (11cm).
Nyasa
The Peach-Faced lovebirds (Agapornis roseicollis roseicollis) are the only type of lovebirds in the intermediate group. They have a green body with a vivid red face and throat. They have blue rumps and a green tail. For the hobbyist, the peach face lovebird sports over 75 mutations. They are 6-7 inches (16-18cm) long.
Peach-Face
The last group, the Sexually dimorphic group (meaning that the adult sexes can easily be distinguished by appearance) includes Abyssinian, Madagascar, Red-Face, and Swindern's Black-Collared lovebirds (although in this group, the Swindern’s sexes are very similar).
The Abyssinian lovebird (Agapornis taranta taranta) is mostly green, with the males having a red brow. The eye ring in males is redder, while the female has a green eye ring. The beak is red and they are 6- 6 1/2 inches (15-16.5cm) long.
Abyssinian
In the Madagascar lovebirds (Agapornis cana cana), the male has a gray upper body and head while the female has a lighter green. The rest of the body of both sexes is varying shades of green with black feather tips and a hazy yellowish color on the chest. The beak is grey and they are medium sized lovebirds at 5 1/2 inches (14cm).
Madagascar
The Red-Face lovebird (Agapornis pullaria pullaria ) is green with some yellow on the under parts. The forehead is red in males, but the females have a lighter orangish red. The rump is bright blue and the beak is red.
Red-Face
Swindern’s Black-collared Lovebirds (Agapornis swinderniana swinderniana) are without a doubt the most rare lovebirds of all. They have a green body with an unmistakable black collar around the back of the neck.
Swindern's
The Abyssinian lovebird (Agapornis taranta taranta) is mostly green, with the males having a red brow. The eye ring in males is redder, while the female has a green eye ring. The beak is red and they are 6- 6 1/2 inches (15-16.5cm) long.
Abyssinian
In the Madagascar lovebirds (Agapornis cana cana), the male has a gray upper body and head while the female has a lighter green. The rest of the body of both sexes is varying shades of green with black feather tips and a hazy yellowish color on the chest. The beak is grey and they are medium sized lovebirds at 5 1/2 inches (14cm).
Madagascar
The Red-Face lovebird (Agapornis pullaria pullaria ) is green with some yellow on the under parts. The forehead is red in males, but the females have a lighter orangish red. The rump is bright blue and the beak is red.
Red-Face
Swindern’s Black-collared Lovebirds (Agapornis swinderniana swinderniana) are without a doubt the most rare lovebirds of all. They have a green body with an unmistakable black collar around the back of the neck.
Swindern's
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