Causus maculatus is venomous

Venomous snake

"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...

 viper

Viperidae

The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...

 species

Species

In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 found mainly in West-

West Africa

West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...

 and Central Africa

Central Africa

Central Africa is a core region of the African continent which includes Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, and Rwanda....

. No subspecies are currently recognized. Common names include forest rhombic night adder, West African night adder and spotted night adder.

Description

These snakes are small and stout, with an average length of 30-60 cm. Grows to a maximum size of about 70 cm, or perhaps slightly larger.

The snout is obtuse with a rounded rostral scale. A single loreal is present. The circumorbital ring consists of 2-3 preoculars, 1-2 postoculars and 1-2 suboculars. There are 6 supralabials and 9-10 sublabials. Four sublabials are in contact with the sublinguals. There are 2-3 temporal scales

Temporal scales

In reptiles, the temporal scales are those scales on the side of the head between the parietal scales and the supralabial scales, and behind the postocular scales.There are two types of temporal scales:...

.

At midbody there are 17-19 rows of dorsal scales

Dorsal scales

In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales.When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17...

. The ventral scales

Ventral scales

In snakes, the ventral scales are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that contacts the paraventral row of dorsal scales on either side...

 number 118-137 in females and 124-144 in males. The subcaudal scales

Subcaudal scales

In snakes, the subcaudal scales are the enlarged plates on the underside of the tail. These scales may be either single or divided and are preceded by the anal scale....

 number 14-23 in females and 15-26 in males. Within the range of this species, the ventral scale counts increase from south to north and from east to west. This diagnostic information is apparently according to Hughes (1977).

Spawls and Branch (1995) give a slightly different description of the body scalation: midbody there are 17-22 rows of dorsal scales, which have been described as soft and feebly keeled. The ventral scales number 124-151 in females and 118-154 in males, with the highest numbers found in specimens from Uganda

Uganda

Uganda , officially the Republic of Uganda, is a landlocked country in East Africa. Uganda is also known as the "Pearl of Africa". It is bordered on the east by Kenya, on the north by South Sudan, on the west by the Democratic Republic of the Congo, on the southwest by Rwanda, and on the south by...

 and Ethiopia

Ethiopia

Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...

.

The color pattern usually consists of a brown ground color, sometimes grayish, olive or light green, with a series of dark brown or blackish patches down the back (this pattern is less distinct on the first quarter of the body). The flanks are sprinkled with black scales. There is much variation in the dorsal pattern; some specimens, especially those from more arid regions, may have no pattern at all, making them hard to identify. Those from DR Congo

Democratic Republic of the Congo

The Democratic Republic of the Congo is a state located in Central Africa. It is the second largest country in Africa by area and the eleventh largest in the world...

 are often a uniform brown. The belly may be white, cream or pinkish-gray. The ventral scales may be uniform in color, but sometimes each scale grades from light to dark, giving the belly a finely barred appearance. The head usually has a distinct V-shaped mark. This mark may be solid black in juveniles, but in adults it becomes brown with a black outline. Sometimes, a short dark line is present extending backwards from the posterior of the eye.

Geographic range

Mauritania

Mauritania

Mauritania is a country in the Maghreb and West Africa. It is bordered by the Atlantic Ocean in the west, by Western Sahara in the north, by Algeria in the northeast, by Mali in the east and southeast, and by Senegal in the southwest...

 and Senegal

Senegal

Senegal , officially the Republic of Senegal , is a country in western Africa. It owes its name to the Sénégal River that borders it to the east and north...

 east to western Ethiopia

Ethiopia

Ethiopia , officially known as the Federal Democratic Republic of Ethiopia, is a country located in the Horn of Africa. It is the second-most populous nation in Africa, with over 82 million inhabitants, and the tenth-largest by area, occupying 1,100,000 km2...

, south to DR Congo

Democratic Republic of the Congo

The Democratic Republic of the Congo is a state located in Central Africa. It is the second largest country in Africa by area and the eleventh largest in the world...

 and northern Angola

Angola

Angola, officially the Republic of Angola , is a country in south-central Africa bordered by Namibia on the south, the Democratic Republic of the Congo on the north, and Zambia on the east; its west coast is on the Atlantic Ocean with Luanda as its capital city...

. The type locality is listed as "Liberia, Western Africa."

Mallow et al. (2003) mostly quote Spawls and Branch (1995), giving the range as West-

West Africa

West Africa or Western Africa is the westernmost region of the African continent. Geopolitically, the UN definition of Western Africa includes the following 16 countries and an area of approximately 5 million square km:-Flags of West Africa:...

 and Central Africa

Central Africa

Central Africa is a core region of the African continent which includes Burundi, the Central African Republic, Chad, the Democratic Republic of the Congo, and Rwanda....

, from Senegal east to Chad

Chad

Chad , officially known as the Republic of Chad, is a landlocked country in Central Africa. It is bordered by Libya to the north, Sudan to the east, the Central African Republic to the south, Cameroon and Nigeria to the southwest, and Niger to the west...

, southeast to DR Congo

Democratic Republic of the Congo

The Democratic Republic of the Congo is a state located in Central Africa. It is the second largest country in Africa by area and the eleventh largest in the world...

 and northeast into southeastern Sudan

Sudan

Sudan , officially the Republic of the Sudan , is a country in North Africa, sometimes considered part of the Middle East politically. It is bordered by Egypt to the north, the Red Sea to the northeast, Eritrea and Ethiopia to the east, South Sudan to the south, the Central African Republic to the...

. Also found in the river gorges and low country of southwestern Ethiopia, southwest to northern Angola and DR Congo.

Habitat

Found in an amazingly wide range of habitats, including forests, savannah and even semi-desert. It may be quite common in parts of its range.

Behavior

Terrestrial, but is known to climb into low bushes in pursuit of frogs. They are relatively slow moving, but can strike quickly, tending to lash rather than to stab. Despite its name, this species is known to be active at any time of the day, evening or night, and has sometimes been seen sunning itself. They are most active during the rainy season (March-October) when their prey is available, virtually disappearing during the dry season.

Reproduction

Oviparous. Lays 6-20 eggs in February-April, with the hatchlings appearing in May-July.

Venom

Bites result in mild symptoms that include pain, moderate swelling, local lymphadentitis and mild fever. Blistering has not been reported while necrosis is rare and usually secondary. The symptoms disappear after two to three days and normally without any complications. No existing antivenins are known to counteract this venom.

Taxonomy

This species was previously considered to be a subspecies of C. rhombeatus

Causus rhombeatus

Causus rhombeatus is a venomous viper species found in subsaharan Africa. No subspecies are currently recognized.-Description:With an average length of 60 cm, this is the largest member of the genus Causus. The longest individual ever recorded was a 93 cm male collected in eastern Zimbabwe.The head...

.

External links

• Causus maculatus image at Adam D. Leaché's homepage. Accessed 6 June 2007.
• Causus maculatus image at Herpetology of Africa. Accessed 6 June 2007.