mucosa , Dhaman, Indian Ratsnake
Ptyas is a genus that belongs to family colubridae of snakes. This is one of several genuses of colubrid genera which are collectively known as "rat snakes". The family Colubridae is the largest family of snake species which includes about two-third of all known living snake species.
Eight species are cited in this group till so far viz. Ptyas mucosa (Linnaeus, 1758); Ptyas dipsas (Schlegel, 1837); Ptyas carinata (Günther, 1858); Ptyas fusca (Günther, 1858); Ptyas dhumnades (Cantor, 1842); Ptyas nigromarginata (Blyth, 1854); Ptyas korros (Schlegel, 1837) & Ptyas luzonensis (Günther, 1873).
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Genus: Ptyas
Species : mucosa
Binomial name
Ptyas mucosa (Linnaeus, 1758)
They all are the medium to large size constrictors snakes & are widely distributed throughout the Northern Hemisphere. They mostly feed on rodents and birds. However, some of the species may grow beyond 8 ft. in total body length; where, when they conquer top levels of some food chains. Most The species of this genra although can be tamed easily, however sometimes can be very aggressive, but bites rarely. Usually try to escape the encounter site. Moreover all of the colubrid snakes are not a threat to humans instead they are absolutely nonvenomous. They are known as the excellent rodent killers and this behavior of theses serpents is very beneficial for agriculture practices and also to ecological equilibrium. In India 279 species of snakes belonging to 28 families have been recognized and family Colubridae alone comprises 158 species of snakes.
Came across this beautiful creature more often, almost during my every visit
Ptyas mucosa is one of the most common species of snakes, which is commonly known as Indian rat snake or oriental rat snake or Dhaman. This species can grow upto 3 m (9.8 ft.) in length & varies in colour from pale browns (in dry regions) to nearly black (in moist forest). It is a diurnal and semi-arboreal snake species that inhabits forest floors and agriculture lands as well as sometimes wetlands and mostly near human settlements. It feeds on frogs, toads, lizards, birds and rats. P. mucosa mates in late spring and early summer; female lays 6-30 eggs of 4 to 5 x 2.5 to 4 cm per clutch in summer and early fall. Hatchlings measure of about 36-41 cm in total length.
This species of snake usually flee when encountered whereas when corned, it expands its throat and neck longitudinally and produces a loud hissing sound. When got caught, it continuously turns its body aggressively, attempt to bite, and sometimes may release anal secretion which has foul smell. It also wraps itself tightly around the handler or catcher. King cobras in south India are the natural predator of adult rat snakes that overlap them in range. Juveniles are in prey list of birds, larger reptiles and mid-sized mammals. Rat snakes and other related snakes of Colubridae family are aggressively hunted by humans in some areas of their range for skins and meat. In many parts of the Asian countries like china and Indonesia it is harvested for their skin and for edible use (Mark, 2010).
The species has been commercially harvested for the international skin trade since the early 20th century (CITES, 2005), The Indian population of this species has been listed in Appendix III of the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) since 1984. In India, this species of snake is often killed by humans because of its larger size and miss-identification with other venomous snakes like common krait. The species of snake has wide-ranging geographical distribution in Asia. From Iran, Turkmenistan, Afghanistan, Pakistan, Sri Lanka, Nepal, Bangladesh, Myanmar, China (Chekiang, Hupeh, Jiangxi, Fujian, Guangdong, Hainan, Guangxi, Yunnan, Xizang, Hong Kong), Thailand, Lao PDR, Cambodia, Viet Nam, Malaysia, Singapore, India (Assam, Tamil Nadu, Kerala, Madhya Pradesh, Himachal Pradesh, Maharashtra, Jammu & Kashmir (Jammu, Doda & Bhaderwah), Karnataka, Punjab, Gujarat, Tripura, & Andaman) Indonesia (Sumatra, Java), Pakistan, Taiwan, Thailand, West Malaysia U.S.S.R., and Vietnam.
Description of the individuals I have sighted during my visits from Central India & from Jammu & Kashmir. On the dorsal side the individuals were having slender body with smooth scales. Head is somewhat pointed, distinct from the neck. Labials have black colour lining over them. Eyes were large and have the distinctive golden iris around. Tongue was purplish-black in colour. The species was having white and yellow colours cross marking dorsally in case of adults and yellowish in juveniles. The colouration that I have observed were black, greenish black, brown and yellow. In black transforms there were no cross marking. On the ventral side they were yellow and white having dark patches on both ends of the scales. Sub-caudal scales were paired. Tail in these snakes was long and slender, pointed towards tip.
Morphological Characters
No. of snakes observed: 9
Supralabial (4th& 5th in contact with eyes) :8/8
Infra-labial :7/7
Pre-ocular:1
Post-ocular :2
Loreal :1 to 4
Temporal : 2+2
Anal: 2(1+1)
Nasal : 2(1+1)
Intranasal: 2
Supraocular :2
Parietal : 2
Frontal :1
Prefrontal:2
Dorsal scales (N:M:V) :15:17:14/17:17:14
Ventral : 166-200
Sub caudal (Paired) :120-130
Body Measurements (mm)
Full body length: 1870-2600
SVL :1390-1945
Tail length: 339-655
Literature Cited:
CITES (2005). Fifty-third meeting of the Standing Committee. Sustainability of Rat Snake (Ptyas mucosus) Harvests in Indonesia: A Discussion of Issues. Available at http://www.cites.org/common/com/SC/53/E53i-03.pdf (Assessed on 2 march 2017).
Günther, A. 1864. The reptiles of British India.Taylor & Francis, London
http://reptile-database.reptarium.cz/species?genus=Ptyas&species=mucosa.
https://en.wikipedia.org/wiki/Ptyas
Manhas A, Kotwal A., Wanganeo R.R, and Wanganeo A. 2015. Diversity, Threats and Conservation of Herpetofauna in and around Barkatullah University, Bhopal (MP), India. International Journal of Advanced Research 3(9):1546-1553.
Manhas A., Raina R. and Wanganeo. A. 2016. Natural history and threats of rat snake (Ptyas mucosus) with special reference to their protection. Int. J. Adv. Res. Sci. Hum. Eng., 1 (2): 1-6.
Manhas, A., Raina R. and Wanganeo, A. 2016. An assessment of reptilian diversity and their distribution in Jammu and Kashmir state from Jammu city in northern India: A case study International Journal of Fauna and Biological Studies 2016; 3(3): 20-23.
Manhas, A., Raina, R. and Wanganeo, A. 2015. Snakes of the Bhopal district, Madhya Pradesh, India with special reference to road mortality. Journal of Research in Biology, 5(7): 1868-1873
Manhas, A., Raina, R. and Wanganeo, A. 2016. An addition to the reptilian diversity of Barkatullah university campus, Bhopal, Madhya Pradesh, India. Int. J. Pure Appl. Zool., 4 (4): 306-309.
Manhas, A., Raina, R. and Wanganeo, A. 2017. Current Status and Diversity of Ophidians (Reptilia: Squamata: Serpents) in Bhopal, Madhya Pradesh, Central India. Int. J. Cur. Micro. Appl. sci., 6 (5): 1384-1390.
Manthey, U. and Grossmann W. 1997. Amphibien und Reptilien Südostasiens. – Natur und Tier Verlag, Münster, 512 pp.
Mark, A. 2010. Conservation status and impact of trade on the Oriental Rat snake (Ptyas mucosus) in java, Indonesia. TRAFFIC Southeast Asia, Petaling Jaya, Selangor, Malaysia, 1-40.
Smith M.A. 1943. Fauna of British India, Vol. 3: Serpentes, Published by Taylor and Francis, London.
Smith, M.A. 1943. The Fauna of British India, Ceylon and Burma, including the whole of the Indo-Chinese Sub-Region. Reptilia and Amphibia. 3 (Serpentes). Taylor and Francis, London.
Traffic 2008. Case study on Ptyas mucosus, a proposed NDF method for Indonesia (Java). NDF workshop WG 7, p16. Available at https://cites.org/sites/default/files/ndf_material/WG7-CS4.pdf (Assessed on 7 march 2016).
Whitaker, R. and Captain, A. 2008. Snakes of India: The field guide (1st edition). Draco Books. Chennai.
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