Walterinnesia aegyptia
Encyclopedia
Walterinnesia aegyptia is a genus
of venomous
elapid snake
, also known as the Desert Black Snake or Desert Cobra. It was long considered to be the only species within the genus
Walterinnesia. However, it was recently found that the eastern populations actually represent a different species, W. morgani. W. aegyptia is entirely black
in color, and has highly shiny scales
. W. morgani differs in having a juvenile pattern of reddish crossbars on the back, and lower average ventral and subcaudal scale counts.
. Walterinnesia aegyptia is found in the countries of Egypt
, Lebanon
, Jordan
, Israel
, and northwestern Saudi Arabia
. It may also be found in areas of Syria
that border Lebanon.
). They can also be found in semi-desert scrublands and rocky terrain, extending into the foothills of vegetated Mediterranean terrain. They are also often found near human habitation in irrigated agricultural settlements.
.
's (naja naja) subcutaneous is 0.45 mg/kg, while the Cape cobra
's (naja nivea) subcutaneous is 0.72 mg/kg. This makes the W. aegyptia (or Desert Black Snake) a more venomous snake than both.
A survey of the literature revealed only a few clinical cases reported. Most of the information concerning W. aegyptia was collected from laboratory and animal studies.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of 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...
elapid snake
Snake
Snakes are elongate, legless, carnivorous reptiles of the suborder Serpentes that can be distinguished from legless lizards by their lack of eyelids and external ears. Like all squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales...
, also known as the Desert Black Snake or Desert Cobra. It was long considered to be the only species within the genus
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Walterinnesia. However, it was recently found that the eastern populations actually represent a different species, W. morgani. W. aegyptia is entirely black
Black
Black is the color of objects that do not emit or reflect light in any part of the visible spectrum; they absorb all such frequencies of light...
in color, and has highly shiny scales
Scale (zoology)
In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...
. W. morgani differs in having a juvenile pattern of reddish crossbars on the back, and lower average ventral and subcaudal scale counts.
Physical description
These snakes are medium in length, with a medium, cylindrical body and a short tail. Their average length is 0.5 metres (1.6 ft), but they can grow to lengths of 1.3 metres (4.3 ft). Their head is moderately small, broad, flattened and slightly distinct from the neck. The snout is broad, sharply edged with a distinct canthus rostralis. The eyes are small in size with round pupils. Dorsal scales are smooth anteriorly and weakly keeled on the posterior part of the body and tail. They are very glossy throughout. Dorsal scale count 27 (24 to 29) - 23 (21 - 25) - 17.Geographical range and habitat
They are native to the Middle EastMiddle East
The Middle East is a region that encompasses Western Asia and Northern Africa. It is often used as a synonym for Near East, in opposition to Far East...
. Walterinnesia aegyptia is found in the countries of Egypt
Egypt
Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...
, Lebanon
Lebanon
Lebanon , officially the Republic of LebanonRepublic of Lebanon is the most common term used by Lebanese government agencies. The term Lebanese Republic, a literal translation of the official Arabic and French names that is not used in today's world. Arabic is the most common language spoken among...
, Jordan
Jordan
Jordan , officially the Hashemite Kingdom of Jordan , Al-Mamlaka al-Urduniyya al-Hashemiyya) is a kingdom on the East Bank of the River Jordan. The country borders Saudi Arabia to the east and south-east, Iraq to the north-east, Syria to the north and the West Bank and Israel to the west, sharing...
, Israel
Israel
The State of Israel is a parliamentary republic located in the Middle East, along the eastern shore of the Mediterranean Sea...
, and northwestern Saudi Arabia
Saudi Arabia
The Kingdom of Saudi Arabia , commonly known in British English as Saudi Arabia and in Arabic as as-Sa‘ūdiyyah , is the largest state in Western Asia by land area, constituting the bulk of the Arabian Peninsula, and the second-largest in the Arab World...
. It may also be found in areas of Syria
Syria
Syria , officially the Syrian Arab Republic , is a country in Western Asia, bordering Lebanon and the Mediterranean Sea to the West, Turkey to the north, Iraq to the east, Jordan to the south, and Israel to the southwest....
that border Lebanon.
Habitat
This species occurs in the desert (excluding completely sand deserts such as the ad-Dahna DesertAd-Dahna Desert
ad-Dahna Desert is the central division of the Arabian Desert. It is a corridor of sandy terrain forming a bow-like shape that connects an-Nafud desert in the north to Rub' al-Khali desert in the south. Its length is more than 1000 km siding Twaik Mountains from the east and does not exceed...
). They can also be found in semi-desert scrublands and rocky terrain, extending into the foothills of vegetated Mediterranean terrain. They are also often found near human habitation in irrigated agricultural settlements.
Behaviour and diet
The Desert black snake are nocturnal and are strictly terrestrial snakes. They are most active around midnight. It actively pursue's and forages for their prey and rather than envenomate its prey with an open mouth, they'll usually bite its prey sideways at short distances and often use constriction and suffocation techniques in addition to their venom to kill their prey. There are reports of this snake being aggressive when molested, but like most snakes, it will usually try to escape rather than immediately bite or face their threat. Venom is not injected immediately when it bites but released seconds later with chewing movement.Diet
This species feeds mainly on lizards, skinks, geckos, agamids, other snakes, toads and occasionally mice and birds. It will also readily eat carrionCarrion
Carrion refers to the carcass of a dead animal. Carrion is an important food source for large carnivores and omnivores in most ecosystems. Examples of carrion-eaters include vultures, hawks, eagles, hyenas, Virginia Opossum, Tasmanian Devils, coyotes, Komodo dragons, and burying beetles...
.
Venom
This species is highly venomous. The subcutaneous for the venom of W. aegyptia is 0.4 mg/kg. For comparison, the Indian cobraIndian Cobra
Indian Cobra or Spectacled Cobra is a species of the genus Naja found in the Indian subcontinent and a member of the "big four", the four species which inflict the most snakebites in India. This snake is revered in Indian mythology and culture, and is often seen with snake charmers...
's (naja naja) subcutaneous is 0.45 mg/kg, while the Cape cobra
Cape Cobra
The Cape Cobra or yellow cobra is a moderately sized, highly venomous cobra inhabiting a wide variety of biomes across Southern Africa...
's (naja nivea) subcutaneous is 0.72 mg/kg. This makes the W. aegyptia (or Desert Black Snake) a more venomous snake than both.
A survey of the literature revealed only a few clinical cases reported. Most of the information concerning W. aegyptia was collected from laboratory and animal studies.