Ahaetulla nasuta - Misplaced Pages

(Redirected from Long-nosed whip snake) Species of venomous, snake

Common vine snake

Conservation status
Least Concern (IUCN 3.1)
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 Dryophis rhodonotus

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.

Etymology

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. The species name nasuta is Latin for "of the nose", in reference to its elongated snout.

Vernacular names

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.

Sinhala: ඇහැටුල්ලා (Pronounced: Aheatulla)
Tamil: பச்சை பாம்பு
Kannada: ಹಸಿರು ಹಾವು
Marathi: हरणटोळ (Pronounced: harantol)
West Bengal: লাউডগা ( Pronounced:Laudoga)

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.

Distribution and Taxonomy

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, although a 2020 study later found A. anomala to be possibly conspecific with Ahaetulla oxyrhyncha.

The cladogram below from a 2019 study shows Ahaetulla nasuta as paraphyletic:

Ahaetuliinae

sharp‑nosed snakes

Ahaetulla

	Ahaetulla prasina (paraphyletic)

	Ahaetulla fasciolata

Ahaetulla prasina (paraphyletic)

	Ahaetulla prasina (paraphyletic)

	Ahaetulla mycterizans

Ahaetulla prasina (paraphyletic)

	Ahaetulla anomala

	Ahaetulla pulverulenta

Ahaetulla nasuta (paraphyletic)

Ahaetulla fronticincta

Proahaetulla antiqua

Dryophiops

broad‑nosed snakes

	Dendrelaphis

	Chrysopelea

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.

Habitat

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.

Description

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.

Taxonomic description

The following description with diagnostic characters is from Boulenger (1890):

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.

Behavior

They feed on lizards and other invertebrates. 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.

Venom and its effects

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.

References

Figueroa, A.; McKelvy, A. D.; Grismer, L. L.; Bell, C. D.; Lailvaux, S. P. (2016). "A species-level phylogeny of extant snakes with description of a new colubrid subfamily and genus". PLOS ONE. 11 (9): e0161070. Bibcode:2016PLoSO..1161070F. doi:10.1371/journal.pone.0161070. PMC 5014348. PMID 27603205.
^ Reptile Database (2016). Ahaetulla nasuta. Retrieved 16 May 2024.
Snakes of Sri Lanka Archived May 19, 2005, at the Wayback Machine
Mohapatra, Pratyush; K Dutta, Sushil; Kar, Niladri Bhusan; Das, Abhijit; Murthy, BHCK; Deepak, V (2017-05-01). "Ahaetulla nasuta anomala (Annandale, 1906) (Squamata: Colubridae), resurrected as a valid species with marked sexual dichromatism". Zootaxa. 4263 (2): 318–332. doi:10.11646/zootaxa.4263.2.6. PMID 28609871. S2CID 41105263.
^ Mallik, Ashok Kumar; Srikanthan, Achyuthan N.; Pal, Saunak P.; D'souza, Princia Margaret; Shanker, Kartik; Ganesh, Sumaithangi Rajagopalan (2020-11-06). "Disentangling vines: a study of morphological crypsis and genetic divergence in vine snakes (Squamata: Colubridae: Ahaetulla) with the description of five new species from Peninsular India". Zootaxa. 4874 (1): zootaxa.4874.1.1. doi:10.11646/zootaxa.4874.1.1. ISSN 1175-5334. PMID 33311335. S2CID 228823754.
Mallik, Ashok Kumar; Achyuthan, N. Srikanthan; Ganesh, Sumaithangi R.; Pal, Saunak P.; Vijayakumar, S. P.; Shanker, Kartik (27 July 2019). "Discovery of a deeply divergent new lineage of vine snake (Colubridae: Ahaetuliinae: Proahaetulla gen. nov.) from the southern Western Ghats of Peninsular India with a revised key for Ahaetuliinae". PLOS ONE. 14 (7): e0218851. Bibcode:2019PLoSO..1418851M. doi:10.1371/journal.pone.0218851. ISSN 1932-6203. PMC 6636718. PMID 31314800.
"WCH Clinical Toxinology Resources".
Brischoux, F.; Pizzatto, L.; Shine, R. (2010). "Insights into the adaptive significance of vertical pupil shape in snakes". Journal of Evolutionary Biology. 23 (9): 1878–1885. doi:10.1111/j.1420-9101.2010.02046.x. ISSN 1420-9101. PMID 20629855. S2CID 23349083.
Boulenger, George A. 1890 The Fauna of British India, Including Ceylon and Burma. Reptilia and Batrachia. Taylor & Francis, London, xviii, 541 pp.
Wall, Frank 1905. A popular treatise on the common Indian snakes. Part 1. J. Bombay Nat. Hist. Soc. 16:533-554.
Snakes of Sri Lanka Archived May 19, 2005, at the Wayback Machine
“Ahaetulla nasuta” at WCH Clinical Toxinology Resources. Accessed on 9.1.2014 at http://www.toxinology.com/fusebox.cfm?fuseaction=main.snakes.display&id=SN0004