Naja ashei

Naja ashei
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Sauropsida
Order: Squamata
Suborder: Serpentes
Family: Elapidae
Genus: Naja
Species: N. ashei
Binomial name
Naja ashei
Wüster and Broadley, 2007

Naja ashei (Ashe's Spitting Cobra or Giant Spitting Cobra) is an African snake. It is the world's largest species of spitting cobra[1] It is found in the dry lowlands of northern and eastern Kenya and similar habitats in northeastern Uganda, southern Ethiopia and southern Somalia.[2]

Its differences to other spitting cobras were realized in the 1960s, but the species was initially regarded by most merely as a brown-colored form of the Black-necked Spitting Cobra (N. nigricollis). Thus, N. ashei was only classified as a distinct species in 2007, by Wolfgang Wüster (Bangor University Wales) and Donald Broadley (Biodiversity Foundation for Africa). Royjan Taylor (Director of the Bio-Ken Snake Farm in Watamu, Kenya) was instrumental in providing specimens, among them the holotype. The specific epithet honors the late James Ashe[1], who founded the Bio-Ken Snake Farm and was one of the first experts to suggest that Naja ashei was a new species.[2]

The Giant Spitting Cobra is most closely related to the Mozambique Spitting Cobra (N. mossambica) and together with this species forms a sister taxon to N. nigricollis.[2]

Contents

Description

Naja ashei is a very large cobra that averages 1.3 metres (4.3 ft) to 2 metres (6.6 ft) in length, and the largest individual spitting cobras measured to date; 2.743 metres (9.00 ft) and 2.819 metres (9.25 ft), in length, probably belong to this species. Some N. nigricollis may also reach such sizes, but this is very exceptional, whereas on the Kenyan coast, N. ashei of more than 2 metres (6.6 ft) are not uncommon.[2]

Very heavily built with big heads, their color varies in different shades of brown from light grey through pale mustard to dark brown. The snake is pale in color along the belly, sometimes with slight speckling or blotches, and has a dark brown throat band. It has 17 to 25 mid-body scale rows, 176 to 219 ventrals, 51 to 69 sub-caudals with an entire anal scale across the vent.[2]

Toxicity

Venom from this snake is very similar to other spitting cobras including N. nigricollis and the Red Spitting Cobra (N. pallida) – both found in the same areas – but is produced in very large quantities by the new species. A single specimen milked at Bio-Ken Snake Farm in 2004 produced a wet venom yield of 6.2ml, weighing 7.1 g, and containing nearly 3 g of toxins.[2]

In absence of dedicated research, recommended treatment of bites is, as for all true cobras, with the appropriate antivenom (SAVP polyvalent from South African Vaccine Producers). The dosage may need to be higher than for the average N. nigricollis bite. First aid treatment for venom in the eyes is immediate irrigation with water or any bland liquid - failure to do so may result in permanent blindness. Whether bitten or spat at, the patient should be seen as soon as possible by a physician. There is no data suggesting that the new species' toxins differ clinically from those of other spitting cobras, except perhaps by the effects of greater dosages on average. Spitting cobra venom has rather low systemic toxicity - meaning that with appropriate treatment, survival of bitten persons is very likely - but a strong necrotizing effect - meaning it kills tissue around the wound[2]. This is the reason why if a successful spitting is not treated immediately, blindness (due to destruction of the cornea) is likely; even in patients treated with antivenom, amputations may become necessary if they receive a full dose of a large spitting cobra's venom. For details, see snake venom.

Footnotes

  1. ^ a b Reuters/ABC News Online: Record-size spitting cobra discovered. 2007-DEC-08. Retrieved 2008-FEB-04.
  2. ^ a b c d e f g Wüster & Broadley (2007)

References

External links