The mole snake is a large strong solid animal with an average length between 1‑1.5 metres. The Cape Peninsula specimens however tend to grow much larger than populations from other areas and readily exceed 1.5m and may reach up to 2 metres in length.
Mole snakes on the Cape peninsula tend to be ebony, glossy black, or light to dark olive brown. Other colour phases seen elsewhere in South Africa include brick-read, cream, various shades of brown, and greys.
The head is small with a pointed snout. Unlike the Cape Cobra, for which this snake is often mistaken, the head doesn’t bulge at the sides to make the head distinct from the rest of the body – the neck isn’t noticeably thinner than the back of the head.
The mole snake is common throughout most of southern Africa. They are often encountered in sandy areas inhabited by moles. Mole snakes spend the vast majority of their time underground. Their muscular build and pointed snout make them adept at pushing themselves through sandy burrows after their prey which consists primarily of golden moles and mole/dune rats. Apart from moles, their diet also includes other species of rodent, nestling birds (especially ground-dwelling species), and eggs (on the peninsula sea-bird eggs are regularly consumed).
There is often confusion when it comes to juvenile mole snakes. Most people tend assume that any small brown snake found in their garden is simply a young mole snake, these however are often the common slug‑eater; a harmless and inoffensive species which plays a useful role in the suburban garden by preying on snails and slugs. In fact juvenile mole snakes aren’t coloured like their parents; they are various shades of brown or red-brown, or dark cream and are patterned with darker blotches or spots in pairs (which are always slightly diagonal to each other), these may be joined in some individuals, forming a zig‑zag along their upper (dorsal) surface.
There are also many smaller spots or mottling, infused around the larger patterning and among these smaller spots are white flecks. Their bellies at this stage of their lives are cream to yellow; on the peninsula their bellies usually have darker lines between the yellow/cream belly scales. Another feature of juvenile mole snakes a red/red-orange coloured eye, this is lost with age. The young are often mistaken for spotted skaapstekers (which are not considered dangerous to humans).
Mole snakes give live birth to an average of 20-50 young, with a maximum of over 90 young having been recorded. These are born from March to April.
Despite being non-venomous, mole snakes are foul tempered snakes which will hiss loudly and strike (often with their mouths agape) at any aggressor. This alarming display of displeasure often results in them being mistaken for a venomous species such as the Cape cobra.
Ecologically; mole snakes play an important part in rodent population control, and themselves serve as part of the food chain for larger species. Their role in rodent control has made them economically important in agriculture, and for this reason they were one of the first species to be protected in the Cape.