Jameson's mamba is a large quick, and highly venomous snake native to equatorial Africa. Adults are usually dull green across the back, blending to pale green towards the underbelly with scales generally edged with black. The ventral side, neck, and throat are typically cream or yellowish in color. Populations that are typically found in the eastern part of the range, feature a black tail, while central and western examples typically have a pale green or yellow tail.
Jameson's mambas occur mostly in Central Africa and West Africa, and in some parts of East Africa. In Central Africa, they can be found from Angola northwards to the Democratic Republic of Congo, Republic of Congo, Central African Republic, and as far north as the Imatong Mountains of South Sudan. In West Africa, they range from Ghana eastwards to Togo, Nigeria, Cameroon, Equatorial Guinea, and Gabon. In East Africa, they can be found in Uganda, Kenya, Rwanda, Burundi, and Tanzania. These snakes inhabit rainforests, woodland, and forest-savanna. Jameson's mambas are adaptable creatures and may occur in areas where there has been extensive deforestation and human development. They are often found around buildings, town parks, farmlands, and plantations.
Jameson's mambas are highly arboreal and agile snakes that come down to the ground only to bask or move to another tree. They are solitary and interact with each other only during the mating season. Jameson's mambas are active diurnal hunters and chase prey, similar to other mamba species. When prey is caught, mambas will strike until the prey dies. When these snakes feel threatened they will flatten their neck in mimicry of a cobra, and their body shape and length give an ability to strike at significant range. Jameson's mambas are not typically aggressive in nature and will almost always attempt to escape.
Jameson's mambas are carnivores and since they spend most of their time in trees birds make up a large portion of their diet. Other prey items include small mammals such as mice, rats, and bats, and small lizards.
Jameson's mambas are oviparous and lay up to 17 eggs. During the breeding season, males fight each other and locate females by following their scent trails.