| Common vine snake | |
|---|---|
 | |
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Suborder: | Serpentes |
| Family: | Colubridae |
| Subfamily: | Ahaetuliinae |
| Genus: | Ahaetulla |
| Species: | A. nasuta |
| Binomial name | |
| Ahaetulla nasuta (Lacépède, 1789) | |
| Synonyms | |
Dryophis nasuta | |
Ahaetulla nasuta, also known as Sri Lankan green vine snake and long-nosed whip snake, is a venomous, slender green tree snake endemic to Sri Lanka.
The genus name Ahaetulla comes from the Sri Lankan Sinhalese words ahaetulla/ahata gulla/as gulla, meaning “eye plucker” or “eye picker”, because of the belief that they pluck out the eyes of humans, as first reported by the Portuguese traveler João Ribeiro in 1685. [1] The species name nasuta is Latin for "of the nose", in reference to its elongated snout. [2] [3]
The Sinhala name "Aheatulla" or "eye-plucker" forms the taxonic genus name. In Tamil, it is known as pachai paambu. In Kannada, it is known as Hasiru Haavu.
In Western internet culture, the vine snake has occasionally been humorously nicknamed as the “judgmental shoelace”, due to their long, slender bodies and the horizontal shape of their pupils resembling a person narrowing their eyes in a captious expression.
Due to longstanding confusion over the taxonomy of A. nasuta, the species was once thought to have a large range from Sri Lanka to peninsular India, including the Western Ghats, along with a disjunct population in Southeast Asia. Recent phylogenetic studies have since found the species to be paraphyletic, and in need of taxonomic revision.
A 2017 study reclassified the former subspecies Ahaetulla nasuta anomala as a distinct species, Ahaetulla anomala , [4] although a 2020 study later found A. anomala to be possibly conspecific with Ahaetulla oxyrhyncha . [5]
The cladogram below from a 2019 study shows Ahaetulla nasuta as paraphyletic: [6]
| Ahaetuliinae |
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
A 2020 phylogenetic study reaffirmed the paraphyletic nature of A. nasuta, and found it to actually comprise a species complex, with the "true" A. nasuta (from which the species was originally described) being restricted to the wet zone of Sri Lanka (including the Sri Lanka lowland and montane rainforests). Four populations from the Western Ghats of India that were formerly grouped with A. nasuta were split into the species A. borealis , A. farnsworthi , A. isabellina , and A. malabarica . The large-bodied form from lowland peninsular India (and possibly the dry zone of the northern portion of Sri Lanka), which was also formerly grouped with A. nasuta, was found to actually be A. oxyrhyncha , and is actually more closely allied with A. pulverulenta and A. sahyadrensis than A. nasuta. Finally, the disjunct population in Southeast Asia was assigned to an as-of-yet undescribed species, tentatively referred to as Ahaetulla cf. fusca, and is a sister species to Ahaetulla laudankia . [5]
It is found in low bushes, shrubs and trees in lowland forest terrain at elevations up to about 1000 metres, particularly near streams and often found near human settlements. [7]
Common vine snakes are diurnal, arboreal, and mildly venomous. They normally feed on frogs and lizards using their binocular vision to hunt. They are slow moving, relying on camouflaging themselves as vines in foliage. They expand their bodies when disturbed to show a black and white scale marking. Also, they may open their mouths in a threat display and point their heads in the direction of the perceived threat. They are the only species of snake with horizontal pupils, compared to the normal vertical slit pupils found in many species of viper. [8]
The following description with diagnostic characters is from Boulenger (1890): [9]
Snout pointed, terminating in a dermal appendage, which is shorter than the eye and formed entirely by the rostral; the length of the snout, without the appendage, about twice the diameter of the eye or rather more. No loreal; internasals and prefrontals in contact with the labials; frontal as long as its distance from the rostral or a little longer, as long as the parietals or a little longer; two preoculars and a small subocular (or one preocular and two suboculars), upper preocular in contact with the frontal; two postoculars; temporals 1+2 or 2+2; upper labials 8, fifth entering the eye; 4 lower labials in contact with the anterior chin-shields, which are shorter than the posterior. Scales in 15 rows. Ventrals 172–188; anal divided; subcaudals 140–166. Bright green or pale brownish, the interstitial skin between the scales black and white on the anterior part of the body, which appears striped when distended; a yellow line along each side of the lower surface. Total length 5 feet: tail 2.
They feed on lizards and other invertebrates. [2] The species is ovoviviparous, giving birth to young that grow within the body of the mother, enclosed within the egg membrane. They may be capable of delayed fertilization; (parthenogenesis is rare but not unknown in snakes) as a female in the London zoo kept in isolation from August, 1885 gave birth in August, 1888. [10]
The components of its venom are unknown.
Bites from this species produce a moderate reaction in humans, causing localized pain, swelling, bruising, and numbness that typically resolves within 72 hours. Any bite near the vital organs should be considered a medical emergency. [11] [12]
Ahaetulla dispar, the Gunther's vine snake, is a species of tree snake endemic to the Western Ghats. It is primarily restricted to the Shola forests of the Southern Western Ghats where it is found often on high-elevation montane grasslands and the low shrub belts.
Günther's whipsnake, Burmese vine snake or river vine snake is a species of fish-eating vine snake found in Southeast Asia.
Ahaetulla prasina is an arboreal, moderately venomous species of opisthoglyphous vine snake in the family Colubridae, found in Southern and Southeast Asia. Its common names include the Asian vine snake, Boie's whip snake, Gunther's whip snake, and the Oriental whip snake.
Brown-speckled whipsnake or brown vine snake is a species of colubrid vine snake endemic to Sri Lanka.
Dendrelaphis pictus, commonly known as either the common bronzeback, painted bronzeback, or Indonesian bronzeback, is a species of colubrid snake found in Southeast Asia.
Ahaetulla, commonly referred to as Asian vine snakes or Asian whip snakes, is a genus of colubrid snakes distributed throughout tropical Asia. They are considered by some scientists to be mildly venomous and are what is commonly termed as 'rear-fanged' or more appropriately, opisthoglyphous, meaning their enlarged teeth or fangs, intended to aid in venom delivery, are located in the back of the upper jaw, instead of in the front as they are in vipers or cobras. As colubrids, Ahaetulla do not possess a true venom gland or a sophisticated venom delivery system. The Duvernoy's gland of this genus, homologous to the venom gland of true venomous snakes, produces a secretion which, though not well studied, is considered not to be medically significant to humans.
Dryophiops philippina, also known as the keel-bellied whipsnake or Philippine whipsnake, a species of rear-fanged colubrid snake that is endemic to the Philippines. One similar species, Dryophiops rubescens exists in Thailand and Malaysia.
Ahaetulla mycterizans, the Malayan green whipsnake or Malayan vine snake, is a slender arboreal colubrid vine snake found in Southeast Asia.
The speckle-headed whipsnake is a species of colubrid vine snake found in Southeast Asia.
Dryophiops is a genus of whip snakes of the family Colubridae, containing two species. They are arboreal tree snakes, found in forests in Southeast Asia.
The variable colored vine snake is a species of opisthoglyphous colubrid vine snake found in Bangladesh and India. It is the first reported sexually dichromatic snake from the Indian Subcontinent, and until 2017 was formerly regarded as a subspecies of the green vine snake, Ahaetulla nasuta.
Dryophiops rubescens, commonly known as the red whip snake, is a species of snake in the colubrid family from Southeast Asia.
Proahaetulla is a monotypic genus of vine snake in the family Colubridae. It contains only one species, the keeled vine snake, which is endemic to the Western Ghats of India. Its natural habitat is montane rainforests of southern Western Ghats.
The northern Western Ghats vine snake is a species of tree snake endemic to the northern Western Ghats of India.
Farnsworth's vine snake is a species of tree snake endemic to the central Western Ghats of India.
The Malabar vine snake, is a species of tree snake endemic to the southern portion of the central Western Ghats of India.
Ahaetulla isabellina, also known as Wall's vine snake, is a species of tree snake endemic to the southern Western Ghats of India.
The Indian vine snake or long-nosed vine snake is a species of diurnal, mildly venomous, arboreal snake distributed in the lowlands of peninsular India.Often mistakenly believed to peck out peoples' eyes, this misconception has led to widespread wanton killing of this species.
Ahaetulla sahyadrensis is a species of tree snake endemic to the Western Ghats of India. It is also reported from Bangladesh.
Dendrelaphis striatus, commonly known as the banded bronzeback or striated bronzeback treesnake, is a species of snake of the family Colubridae found in Southeast Asia.
