ASI Newsletter - November 2018 

Colour Variation in Snakes

The colour of certain snake species can vary extensively and often causes considerable confusion when it comes to identification. These variations can be regional: for example, Spotted Bush Snakes from Limpopo will be green in the front half with a coppery brown tail compared to the full bright green coloured animals from KwaZulu-Natal. In the western parts of the Eastern Cape, the Spotted Bush Snakes might have none or very few spots. All these different variations can confuse people trying to identify snakes and often arguments follow a pattern of “It can’t be that, I’ve seen that species before and it didn’t look like that”. However, with the use of distribution maps, characteristic features and an open mind to colour variation, identification of snakes shouldn’t be too tricky. Below, we discuss six common species which often cause confusion and the colour variations they can occur in. Additionally, we’ll briefly look at some exceptions that occasionally occur in other species.  

Cape Cobra (Naja nivea)

Probably one of the most variable coloured cobras in Africa. They can occur in all shades of yellow to brown, from light tan to lemon yellow, to yellow with brown spots, to brown with yellow spots, all the way to almost black. In some areas the Cape Cobras will be the same colour, for example, Cape Cobras in the Kalahari are generally lemon to golden yellow, whereas Cape Cobras around Grahamstown are usually dirty yellow with brown and black speckles. In other areas such as Cape Town, you can find almost any colour variety.

Common Slug-eater (Duberria lutrix)

The Common Slug-eater is another species that occurs in a wide variety of colours. Generally, Slug-eaters are red or tan in colour, but they can also be almost black or a mix of shades of red, black and tan, or pale tan with a line of spots down the back, or a two tone of any of the above colours. Around Port Elizabeth the Slug-eaters are usually shades of red, but just outside the city on the Elandsberg Mountains they are tan. In the Transkei they are usually almost black and individuals from Swaziland can also be very dark. In the Durban area, although not common, they are usually tan coloured. They have clean white bellies, often edged with light blue, with a series of faint dark dots bordering the length of the snake’s belly. 

Mole Snake (Pseudaspis cana)

Mole Snakes are well known to change colour as they age. Juvenile Mole Snakes are light brown with a series of patterns and zigzags down the back. As they age, they change colour into plain shades of brown, red, tan, yellow and black. Mole Snakes generally stick to colour variation within distribution. Along the coast from around St Francis in the Eastern Cape, past Cape Town up to Port Nolloth and inland into the Kalahari, they are usually pitch black. Inland in the Northern Cape into the Free State they are slate grey to olive grey. In the grasslands of KZN, Mpumalanga and Gauteng and into the bush of the North-west and Limpopo they are usually tan to yellowish brown in colour. Around Port Elizabeth and into the Transkei they are often reddish in colour, and sometimes retain faint juvenile patterns.

Puff Adder (Bitis arietans)

Puff Adders are generally standard in pattern, having chevrons on the first half of the body changing into lines and blotches near the tail. However, colour can vary from yellow and black, brown and black, and grey and black – all with white lines and spots. Juveniles and specimens from central Africa can also have some orange and even red. There are individuals that are occasionally found that are brownish green with a single white stripe down the centre of the back.

Red-lipped Herald (Crotaphopeltis hotamboeia)

The common name Red-lipped Herald is a bit misleading as this species’ upper ‘red lip’ can range in colour from white, yellow, or orange to red. The snake’s body colour can also be a variety of colours from grey to almost black, and then olive to brown, sometimes with white specks. Lip colour can vary even in the same locality and white lipped varieties sometimes confuse people who are used to the bright red lips.

Rinkhals (Hemachatus haemachatus)

Rinkhals are well known as grey to almost black snakes with two or three white bars on the throat. However, individuals from Clarens, the Natal Midlands and much of the Eastern and Western Cape will be black with yellow bands or even somewhat orange bands. Individuals from Mpumalanga and some areas of Gauteng can also be grey or brown, often with black specs. Occasionally, individuals from Grahamstown and Bloemfontein have been found to be pitch black without any white bars on the throat and resemble the Black Spitting Cobras (Naja nigricincta woodi). Black Spitting Cobras occur in Namaqualand and don’t have keeled scales like the Rinkhals.

Plain forms and melanistic snakes 

Occasionally there are other variations that occur in snakes, but these are not common. There are a few species that occur in a plain form (without the patterns) or in the standard colours we see typically. The Cross-marked Grass Snake (Psammophis crucifer), Rhombic Egg-eater (Dasypeltis scabra) and Karoo Sand Snake (Psammophis notostictus) are well known for having a plain form. This often throws people off and confuses them. Additionally, some snakes have a melanistic form (darkening of pigment making them appear black). It has been recorded in the Western Natal Green Snake (Philothamnus occidentalis) and Green Water Snake (Philothamnus hoplogaster) as well as the Spotted Skaapsteker (Psammophylax rhombeatus). Melanistic Western Natal Green Snakes are common around the Garden Route in the Western Cape.

Colour variations can be tricky, and it is best to read as many books on the subject as possible. Most snake books discuss colour of each species and if you intend to get better at snake identification, it’s a good idea to read up each species.

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