Causus defilippii

Common names: snouted night adder.^[2][3]

Causus defilippii is a venomous viper species found in East Africa. No subspecies are currently recognized.^[4]

Additional recommended knowledge

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Daily Visual Balance Check

Description

The average length is 20-35 cm, rarely exceeding 50 cm.^[2]

The head is short and wide and the snout is prominent, pointed and upturned. The rostral is large. The eyes are medium sized. The circumorbital ring consists of 1-2 preocular scales, 1-2 postoculars and 1-2 suboculars that separate the eye from the supralabials. There are a total of 6-7 supralabials and 7-10 sublabials. The first 3-4 sublabials are in contact with the chin shields. The posterior chin shields are very small and indistinguishable from other posterior scales. The temporal scales number 2+3, sometimes 2+4 and rarely 1+2.^[2]

Midbody there are 16-18 rows of weakly keeled dorsal scales that have a velvety appearance. There are 108-128 ventral scales: rarely more that 117 in males or less than 118 in females. The anal scale is single. The subcaudals number 10-19: seldom less than 14 in males or more than 15 in females.^[2]

The color pattern consists of a light brown, pinkish brown to gray or grayish green ground color, overlaid with a series of 20-30 crescent-shaped dark markings that run down the back. However, these marking may be indistinct. The head has a characteristic V-shaped marking with the apex on the frontal plate. There is also an oblique dark streak present behind the eye. The belly is yellowish while, uniformly colored or with scattered small grayish brown spots. Juvenile specimens are commonly a glossy black or gray.^[2]

Geographic range

Found in coastal Kenya and Tanzania through eastern Africa (Malawi, Zambia, Zimbabwe, Mozambique) to South Africa (Northern, Mpumalanga and KwaZulu-Natal Provinces) as far south as Durban, and on Zanzibar Island. The type locality was originally listed as "Buenos Ayres"; obviously a mistake. Africa, according to Broadley (1971), Puku.^[1]

Habitat

Occurs in moist and dry savanna, coastal thickets and forests from sea level to around 1800 m altitude.^[5] They favor moist surroundings, but have also been found in dry areas on rocky hillsides and escarpments.^[2]

Behavior

Generally nocturnal, but not entirely. They are mostly terrestrial, but sometimes climb into low vegetation in pursuit of frogs and are also good swimmers. When not basking, they remain hidden in ground cover, brush piles and in holes. If disturbed, they inflate themselves and hiss.^[2] They are slow-moving for the most part, but can strike quickly.^[5] In captivity, however, they soon become tame and unwilling to strike.^[2]

Venom

Little is known about the venom, but the symptoms described in the few existing cases histories include rapid swelling, fever, sometimes intense pain and occasionally lymphadenopathy. The swelling usually subsided after 2-3 days and there have not been any reports of necrosis. Currently, there is no antivenin that provides protection against bites from this species.^[5]

See also

• Causinae by common name
• Causinae by taxonomic synonyms
• Snakebite

References