Daboia

Russell's viper is the most widely distributed Viper family member which is infamous for its fascinating whistle and long fangs. This is one of the most bite and death causing venomous snake in Indian subcontinent and the member of Big Four of India. It can be easily identified by checking oval shaped hollow or solid spots in three rows in dorsal body and highly keeled non-shiny scales. However even with specific body patterns layman sometime assume it to be juvenile of Python. The dorsal scales are strongly keeled; only the lower row is smooth. Mid-body, the dorsal scales number 27–33. The ventral scales number 153–180. The anal plate is not divided. The tail is short about 14% of the total body length — with the paired subcaudals numbering 41–68.

DIAGNOSTICS CHARACTERS

Head:

10–12 Supralabials; 10–15 small size scales around the eyes.

Dorsal:

Highly keeled scales in 25–29:27–33:21–23 rows.

Ventral:

153–180; anal undivided.

Sub- caudal:

41-64; divided.

REPRODUCTION

Ovoviviparous (5–66 live offspring), Mating season starts from winters and usually retains up to starting of summer. Male combat also observed during the same period to show dominance for breeding female. Reproduction ovoviviparous; female directly gives birth to 6-96 young during summer to monsoon months. Such large clutch size is not found in any other Viper or Pit Viper of India. However, in such large clutch size many individuals usually born dead or die after few hours of birth due to lack of proper nutrition and lack of proper development during gestation. 

SIZE

New born- 24cm.

Average length- 100cm (3.3ft).

Maximum length- 180cm (6ft).

MORPHOLOGY

Dorsal:

Body stout, robust and covered with highly keeled pointed and dry looking scales. Dorsal light or dark greyish-brown, reddish, orange or entirely gray occasionally. Color and patterns become faint in adults or sometimes adults fund to be completely pattern less. Continuous or discontinuous eye or almond like hollow or solid spots of dark brown or blackish color present in three longitudinal rows along the body; starts from head and generally become faint or absent on tail side. Side spots smaller and more rounded than spots present on the top and generally discontinuous.

Ventral:

Belly white or light yellow with deep dark brown or blackish semi lunar spots on the edge of most of ventral scales. Underside of tail usually darker (brown or deep yellow) than ventral scales with paired subcaudals.

Head:

Head triangular, pointed with small keeled scales; clearly broader than neck. Two triangular shaped spots of rounded edge present on the top. Upper lip pinkish white mostly. Supra nasal crescentic with large nostril. Moderate eyes have vertically elliptical pupil. Two very long fangs present in front side of mouth from birth.

Tail:

Rather small tail with pointed tip and covered with typical keeled scales; usually without patterns. 10-15 scales around eyes; Supralabials: 10-12; Infralabials: 13-16; Dorsal scale row formula: 25-29: 27-33: 21-23. Ventrals: 153-180; Subcaudals: 40-64 (divided). Head triangular, dorsum brown or yellowish brown. Black or brown oval spots arranged in three rows runs along the body axis. Head has inverted “V” mark. Venter white with crescent marks.

ECOLOGY

Crepuscular and nocturnal. Feeds on rodents, frogs and lizards.

BEHAVIOUR

Russell's viper is a nocturnal species which choose nights for foraging and other life activities. Seen at daytime during basking which can retain for most of the day during winters. Shows terrestrial activity and choose drier surrounding. Locomotion usually slow but creeps in somewhat jumpy manner after threatening. Behaviour alert and aggressive if one comes under its attacking range or sitting site. On provocation make a plate like rounded coil with head at center and produce whistle or pressure cooker like sound to alarm its enemy. On further disturbance gives random attacks to scratch enemy's body parts and may or may not deliver its haemotoxic venom.  

Feeds chiefly on rodents; also feeds on birds, lizards, frogs and small mammals.

VENOMOSITY

The Russell's viper, is a highly venomous snake species found in South Asia. Russell's vipers are known for their potent venom and are responsible for a significant number of snakebite incidents in their range. The venom of the Daboia species contains a mixture of toxins, including hemotoxins, which affect the blood and tissues.

GENERAL HABITAT

Found both in plains and moderate elevation up to approximately 4800ft; more common in plains. Distributed in variety of forests including rainforest, mixed, dry, moist deciduous forest, scrub lands, grassland, wetland etc. Habitat includes dry open lands, agricultural fields, open country, scrubs having low bushes, rocky terrain having mounds & vegetation etc. Hides in mounds, holes, piles, caves, cracks, dense leaf litters, dense vegetation etc.