The African darter differs from most other waterbirds in that its feathers do not contain any oil and do not, therefore, repel water. This means that the darter is less buoyant and it is able to dive more easily. It does mean, though, that the feathers can become waterlogged during diving and in order to enable the bird to fly and also to assist in restoring the feathers insulating properties, the feathers must be dried. For this reason the African darter is often seen perched on a convenient rock or tree with its wings spread wide to the sun and the wind.

The darter is sometimes referred to as the Snakebird, a name derived from the fact that it swims very low in the water, with just its long, snake-like neck and narrow head protruding above the surface as it moves forward with snake-like movements.

Fairly common resident in all but the driest areas of Southern Africa, darters are found on almost any inland body of water of any size and preferring quiet dams and slow-flowing rivers. The African darter is fairly large, with a length of approximately 80 cm. It is slender, mostly very dark in colour, with a long neck and a fairly long tail. Eyes are golden yellow. The yellowish-brown bill is straight and pointed, without the hook that is common to the cormorants. The front of the neck is light chestnut. The sexes are similar.

African darters feed mainly on fish, but also on frogs and arthropods. Fish are usually speared with the sharp beak as the birds swim underwater.

The darters are usually silent, although they may croak harshly while roosting. The nest is a platform of sticks that is about a half a metre in diameter. It is a colonial nester, often sharing a site with cormorants and herons. The nest is built in a tree or bush, most commonly over water. The female lays 3 to 5 greenish or bluish eggs that hatch after an incubation period of approximately 25 days.

The scientific binomial of the African darter is Anhinga rufa; Anhinga being a South American native tribal name for the darter and rufa or rufus being the Latin for red.