The Genus Poicephalus are small to medium sized, stocky birds with short, squarish tails and proportionately substantial bills.
www.wingscc.com/aps/poicep.htm
The Red Bellied is similar in shape and a slightly larger bird than the Senegal and the Brown headed but here the sexes are sexually dimorphic. A green/grey colored bird with green under parts except for the cock bird which has as its name suggests "a deep orange belly".
www.wingscc.com/aps/redbell.htm
The Brown Headed is another green bird with a brownish grey head similar to a Senegal but does not have the colored belly. It has yellow under the wings at the front which unfortunately can only be seen properly when in flight. The iris is a greyish yellow, not a bright yellow as the Senegal. This species is also split into 3 sub species.
www.wingscc.com/aps/brown.htm
Jardines are larger than the other Poicephalus species except the Cape parrot. Resembling a small amazon parrot than the Senegal, Brown Headed Red bellied or Meyers, they originate in a band across Central Africa from Liberia across to Tanzania. They are split up into 3 clearly identifiable subspecies.
www.wingscc.com/aps/jardine.htm
This is the largest bird in the Poicephalus group, similar to the nominate Jardine in build, stature and coloring except for the head which is silver with greenish to yellowish flecking, sometimes with a reddish frontal band. It is larger than the Jardine and is easily identifiable by its massive beak. There are three accepted subspecies.
www.wingscc.com/aps/cape.htm
Imported in large numbers, is maybe only second to the Senegal for numbers held by breeders. Similar again in shape and size to the Senegal, Brown headed and Red Bellied. Also has red iris like the Red bellied. It is a brownish grey bird with yellow patches on the bend of the wings and thighs and dependent on subspecies also on the head. Has either a green wash or blue wash to its belly. It comes from Central and Eastern Africa, an extremely large land mass and is possibly split up into six subspecies.
www.wingscc.com/aps/meyers.htm
Similar in color and shape to the Brown headed but larger. Somewhere in between the size of that and the Jardine but also differs by the fact it has red iris.
www.wingscc.com/aps/niam.htm
Similar in shape to the Jardine but of a paler green. Also there is no red or orange/ red markings on the body or head, instead as its name suggests it has a large area of yellow around the face extending into the crown and around the eyes.
www.wingscc.com/aps/yellow.htm