The variable colored vine snake (Ahaetulla anomala) is a species of opisthoglyphous (rear-fanged venomous) snake in the family Colubridae. 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.[2]
| Ahaetulla anomala | |
|---|---|
| |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Reptilia |
| Order: | Squamata |
| Suborder: | Serpentes |
| Family: | Colubridae |
| Genus: | Ahaetulla |
| Species: | A. anomala
|
| Binomial name | |
| Ahaetulla anomala (Annandale, 1906)
| |
Description edit
This species is sexually dichromatic. Males are green and resemble the long-nosed whip snake (Ahaetulla nasuta), while females are brown in color and physically resemble the brown-speckled whipsnake (Ahaetulla pulverulenta).
Distribution edit
It is limited to India (Odisha, West Bengal, Jharkhand, Bihar) and Bangladesh.
Characteristics edit
Ahaetulla anomala shows color polymorphism and has a gradient of green and brown colour. Sexual dichromatism is rare among snakes and is mostly only documented in some groups such as vipers (Bothrops), Comoran snakes (Lycodryas), and Malagasy leaf-nosed snakes (Langaha madagascariensis).
History edit
This snake was first described by Thomas Nelson Annandale (the first director of the Zoological Survey of India) in 1906.
For more than 100 years, its sexually dimorphic coloring led to confusion of females with the brown vine snake and the males with the long-nosed whip snake. To resolve this confusion, a team of biologists conducted a molecular and morphological study of the snake, ultimately finding it to be a distinct species.
A 2020 study found A. anomala to be possibly conspecific with A. oxyrhyncha.[3]
References edit
- ^ Mohapatra, P.; Khan, M.M.H. (2021). "Ahaetulla anomala". IUCN Red List of Threatened Species. 2021: e.T115604283A115604285. doi:10.2305/IUCN.UK.2021-3.RLTS.T115604283A115604285.en. Retrieved 23 April 2023.
- ^ 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.