Anchieta's cobra

Anchieta's cobra
Anchieta's cobra
Scientific classification
Kingdom: Animalia Phylum: Chordata Subphylum: Vertebrata Class: Reptilia Order: Squamata Suborder: Serpentes Family: Elapidae Subfamily: Elapinae Genus: Naja Laurenti, 1768 Species: N. anchietae
Binomial name
Naja anchietae Bocage, 1879
Synonyms
Naja anchietae Bocage, 1879 Naja haje Boettger, 1887 Naia anchietae Boulenger, 1896 Naja haje anchietae Mertens, 1937 Naja haje anchietae Bogert, 1943 Naja haje anchietae Auerbach, 1987 Naja haje anchietae Spawls & Branch, 1995 Naja annulifera anchietae Broadley, 1995 Naja anchietae Broadley & Wüster, 2004 Naja (Uraeus) anchietae Wallach et al, 2009

The Anchieta's cobra (Naja anchietae), also called the Angolan cobra is a species of cobra in the Elapidae family; it is native to the southern regions of Africa.

Etymology

The Anchieta's cobra was first described by Portuguese zoologist José Vicente Barbosa du Bocage in 1879. The generic name Naja is a Latinisation of the Sanskrit word nāgá (नाग) meaning "cobra". The specific epithet anchietae refers to José de Anchieta, a Portuguese explorer of Africa.

Description

The Anchieta's cobra is a medium to large, slightly depressed, tapered and moderately slender bodied snake with a medium length tail. The body of the snake is compressed dorsoventrally and subcylindrical posteriorly. This cobra species can easily be identified by its relatively large and quite impressive hood, which it expands when threatened. The head of this species is broad, flattened and slightly distinct from the neck. The canthus is distinct. The snout is rounded. The eyes are medium in size with round pupils. Dorsal scales are smooth, shiny, without pits and oblique. Adults average around 1.0 m (3.28 ft) but it is not uncommon to find specimens between 1.2 m (3.94 ft) and 1.8 m (5.91 ft) in length. Maximum size attained by this species is just a bit over 2.0 m (6.56 ft), but these are rare cases. The longest recorded male was 2.31 m (7.58 ft) long and was caught in Windhoek, Namibia. The longest recorded female was slightly shorter at 2.18 m (7.15 ft) and was found 25 km (15.53 mi) south of Shakawe, Botswana.

Juveniles are yellow above and below, dorsally with dark scale margins forming irregular transverse lines and a broad black band encircling the neck. Adults gradually darken to light or dark brown, the dark band on the neck fades out. The venter is usually yellow, heavily blotched with dark brown, and the throat band, covering ventrals 12-23, becomes purple-brown. A banded phase sometimes occurs in the southern part of the species' range, black with six to eight yellow bands on the body and one to three on the tail. The light bands are usually as wide or wider than the dark ones. This banded phase has been noted in 13% of males and 22% of females.

Scalation

Midbody scales are in 17 rows with 179-200 ventrals. There are 51-56 paired subcaudals and the anal shield is entire. There are 7 (sometimes 8) upper labials that do not enter the eye and 8 or 9 (rarely 10) lower labials, as well as 1 preocular and 2 postoculars. Temporals are variable, 1+2 or 1+3.

Distribution and habitat

Geographical distribution

This species is mainly limited to southeastern Africa and it can be found in southern Angola, northern Namibia, northern Botswana, western Zambia and parts of northwestern Zimbabwe. Previous reports also included Mozambique, Malawi, Swaziland and southern Democratic Republic of the Congo.

Habitat

The Anchieta's cobras preferred habitat is mesic savanna grasslands, semi deserts, rocky areas but is also often found nearby or in humans settlements, where they sometimes seek shelter under houses. It is especially found in wooded areas along rivers and wetlands. This cobra is never found in forest or desert regions. This species is usually found at low altitudes, but it has been observed at elevations of 2000 m (6561.68 ft) above sea level.

Behaviour and ecology

Behaviour

This is a terrestrial and nocturnal species, foraging for food from dusk onwards, often venturing into poultry runs. During the day it is often seen basking near its preferred retreat, usually an abandoned termite mound, a hole in a rock, hollow tree or under dense vegetation. Although primarily ground dwelling it can also be found in small shrubs. The Anchieta's cobra is more aggressive than closely related species such as the Snouted cobra, but otherwise similar in habits. Although this species will posture in a hostile way when provoked, it will flee when given the opportunity. It has been known to feign death, but it is not as inclined to display this behaviour as is the Rinkhals (Hemachatus haemachatus). This is not a spitting cobra.

Diet

This cobra is a feeding generalist, preying on amphibians such as toads and frogs, other reptiles including lizards and other snakes, birds (including poultry), birds eggs, and mammals such as rats and mice.

Predators

The Anchieta's cobra is preyed upon by birds of prey (particularly secretary birds and snake eagles), mammalian carnivores (e.g. mongooses) and other snakes.

Reproduction

Like other cobras it is oviparous, laying between 47 and 60 eggs in early summer. Hatchlings average between 22 cm (8.66 in) and 34 cm (13.39 in) in length and are completely independent at birth.

Venom

Venom of this species is primarily neurotoxic and cardiotoxic. As a relatively large species, it can inject relatively large quantities of venom in a single bite. It has been known to have caused human fatalities.