Common non-venomous and venomous snakes of Assam, India and their conservation status

Lonie Lahkar Ph.D Research Scholar, Dept. of Zoology, Gauhati University Jaydev Mandal Assistant Professor, Dept. of Zoology, Madhab Choudhury College, Barpeta Tilak Kumar Pradhan Assam Wildlife Rescue and Research Organization, Rajbari, Bihpuria, Lakhimpur

Lonie Lahkar

Lonie Lahkar

Jaydev Mandal

Jaydev Mandal

Tilak Kumar Pradhan

Tilak Kumar Pradhan

Assam is a home to a number of non-venomous, mildly venomous, and venomous snakes. Some of the common snakes of the region are compiled in this report.

 

Non-venomous

Family Colubridae

 

  1. Chinese Ratsnake/ Eastern Rat Snake

Scientific Name: Ptyas korros (Schlegel, 1837)

Description: Body is slender; head is elongate, distinct from neck; and eyes are large with rounded pupils. Dorsal side is grey or olive brown, posterior side is darker. Body scales edged with white, appearing as white bands on black background. The lower surface is cream or whitish. Length of head and body is approximately 220cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Painted Bronzeback Tree Snake

Scientific Name: Dendrelaphis pictus (Gmelin, 1789)

Description: Body is slender; head is distinct from body and eyes are large with rounded pupils. The snake's colouration is brownish olive or bronze-brown above with a yellow lateral stripe. A black stripe on each side of the head passes through the eye widens or breaks up into spots, separated by bluish-green bands on the nape. The lower surface is yellowish or greenish in colour. Length of head and body is approximately 120cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Blue Bronzeback Tree Snake

Scientific Name: Dendrelaphis cyanochloris (Wall, 1921) 

Description:  Body is slender; head is distinct from body, slightly flattened; and eyes are large with rounded pupils. Dorsal is smooth and olive or bronze coloured. In the anterior part of the body, there are groups of dorsals with white. No light ventrolateral stripe. Lower surface is pale greenish. Length of head and body is approximately 133cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Walls’s Bronzeback Tree Snake/Gore's Bronzeback

Scientific Name: Dendrelaphis biloreatus (Wall, 1908) 

Description:  Dorsal side is brownish bronze. A black stripe is present on each side of head, extending to neck. A dark stripe runs along the sides of the body. Ventral side is light green or grey.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Ornate Flying Snake

Scientific Name: Chrysopelea ornata (Shaw, 1802)

Description:  Body is slender; head is depressed; and eyes are large with rounded pupils. Body colour is greenish with variable amount of black on posterior and central of scales. From neck to tail top of the dorsal are marked with oval shaped red patches; between these patches black and yellow found and forms a continuous chain of red, black and yellow colors. Lower side is yellowish-green without any pattern.  Length of head and body is approximately 175cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Copper-headed Trinket Snake

Scientific Name: Coelognathus radiatus (Boie, 1827)

Description:  Body is slender; snout is long; and eyes are large with rounded pupils.  Dorsal color is grayish-brown, fawn or reddish brown with four black stripes on anterior half of body which also have laterally arranged chains. Head color is copper with a fine black streak on nape which joins with a same color streak coming behind the eyes. Two more streaks starts from eyes and pass through upper lips. Ventral body color is uniform whitish, gray or yellow. Length of head and body is approximately 230cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Green Trinket Snake

Scientific Name: Gonyosoma prasinum (Blyth, 1854)

Description:  Body is slender; snout is rounded; head is slightly distinct from neck.  Dorsal side is green and sometimes with brown tail-tip. Indistinct dark postocular stripe and chin cream coloured. Belly is pale green or yellowish green in colour. Length of head and body is approximately 120cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Black-banded Trinket Snake/ Red Mountain Rat snake/ Red Bamboo Snake

Scientific Name: Lycodon jara (Shaw, 1802)

Description:  Body is slender; head is flattened, slightly boarder than neck. Dorsum is dark chocolate brown or jet black with purple tinge. It can be easily identified by its yellowish spots spread uniformly on dorsal body giving overall appearance of greenish-yellow dotted on dark color dorsal. Dorsal side is green and sometimes with brown tail-tip. Indistinct dark postocular stripe and chin cream coloured. Ventral is pale green or yellowish green in colour. Length of head and body is approximately 55cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Twin-spotted Wolf Snake/ Yellow-speckled Wolf Snake

Scientific Name: Lycodon jara (Shaw, 1802)

Description:  Body is slender; head is flattened, slightly boarder than neck. Dorsum is dark chocolate brown or jet black with purple tinge. It can be easily identified by its yellowish spots spread uniformly on dorsal body giving overall appearance of greenish-yellow dotted on dark color dorsal. Dorsal side is green and sometimes with brown tail-tip. Indistinct dark postocular stripe and chin cream coloured. Ventral is pale green or yellowish green in colour. Length of head and body is approximately 55cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Common Wolf Snake

Scientific Name: Lycodon aulicus (Linnaeus, 1758)

Description:  Body is slender; head is distinctly flattened, broader than neck; and snout projects beyond lower jaw. Dorsal scales are brownish coloured or brown mixed with greyish or reddish color having yellow or yellowish-white cross bands, sometimes speckled with brown with become faint on tail region. Belly is glossy white without any pattern. Length of head and body is approximately 80cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Banded Wolf Snake

Scientific Name: Lycodon fasciatus (Anderson, 1879)

Description:  Body is slender and cylindrical; head is flattened; eyes small with flattened pupils. Its dorsal side is purplish black coloured having yellowish or creamy brown crossbars. Ventral side is blotched with white with intermediate thick black stripes. Length of head and body is approximately 85cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Large-toothed Wolf Snake/ Northern Wolf Snake/ White-banded Wolf Snake

Scientific Name: Lycodon septentrionalis (Günther, 1875) 

Description:  Body is slender, elongated and slightly compressed; head is short and flattened; eyes moderate with elliptical pupils. Dorsum is purplish black with narrow white transverse bands. Belly is white, sometimes spotted or barred with black. Length of head and body is approximately 180cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Zaw’s Wolf Snake

Scientific Name: Lycodon zawi (Slowinski, Pawar, Win, Thin, Gyi, Oo & Tun, 2001)

Description:  Body is slender; head is flattened, broader than neck; eyes small with vertical pupils.  Dorsal body color is brownish-black with narrow milky white or yellowish-white cross bands from posterior of neck up to end of tail where they usually become faint. Neck is un-banded. Upper lip color is pale brown or lighter than dorsal color. Ventral is creamy white. Length of head and body is approximately 70cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Light-barred Kukri Snake/White-barred Kukri Snake

Scientific Name: Oligodon albocinctus (Cantor, 1839)

Description: Kukri snakes have characteristic kukri-like teeth used for splicing of eggs. Body is stout, cylindrical; head is short; snout is blunt and rounded; eyes with round pupils. Dorsal is brown or brownish-red with white or light yellow coloured crossbars with black edges.  A dark “V” shaped mark, present on head in contact with longitudinal stripe. Venter is cream, yellow or coral red with black spots on the edge of scales. Length of head and body is approximately 76cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Grey Kukri Snake/Black-barred Kukri Snake

Scientific Name: Oligodon cinereus (Günther, 1864)

Description:  Kukri snakes have characteristic kukri-like teeth used for splicing of eggs. Body is stout, cylindrical; head is short, indistinct from neck; snout is blunt and rounded; eyes moderate with round pupils. Dorsal is red or brownish-red, unpatterned or with with white or light grey crossbars. No “V” mark on head. Venter is cream coloured with dark spots. Length of head and body is approximately 73cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Cantor's Kukri Snake

Scientific Name:

Description: Kukri snakes have characteristic kukri-like teeth used for splicing of eggs. Body is stout, cylindrical; snout is blunt and rounded; eyes with round pupils. Dorsum is with yellowish brown or reddish brown with dark reticulation or with transverse black bars. Head has a dark inverted “V” mark. Belly is whitish and with black spots sometimes. Length of head and body is approximately 95cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Spot-tailed Kukri Snake/ Gray's Kukri Snake

Scientific Name: Oligodon dorsalis (Gray, 1834)

Description: Kukri snakes have characteristic kukri-like teeth used for splicing of eggs.  Body is stout, cylindrical; head is short; snout is blunt and rounded; eyes with round pupils. Dorsal side is dark brown or purplish with c ream coloured vertebral stripe, sometimes with black edges. Tip of tail has 2-3 large black spots, head is dark coloured. Anterior part of venter is black and posterior part is white or yellow. Length of head and body is approximately 50cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Red–striped kukri snake/Namsang Kukri Snake

Scientific Name: Oligodon dorsalis (Gray, 1834)

Description: Kukri snakes have characteristic kukri-like teeth used for splicing of eggs.  Body is stout, cylindrical; eyes with round pupils. Dorsal side is brown with light red vertebral stripe. Narrow dark cross bars are present on the body and some in tail region.  Venter is yellowish with square black spots on outer margins.

Conservation Status: IUCN Red List: Data Deficient (DD); IWPA, 1972: Schedule IV

 

  1. Collared Black-headed Snake

Scientific Name: Sibynophis collaris (Gray, 1853)

Description: Body is slender; head relatively short; eyes with round pupils. Dorsal side is brown or greyish brown with black vertebral region comprising black spots and a line of small black spots runs along body axis. Dark cross bar is present on the head behind the eyes. Ventral side is yellowish in colour with outer black spots. Length of head and body is approximately 75cm.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

Family Pythonidae

 

  1. Burmese Python

Scientific Name: Python bivittatus (Kuhl, 1820)

Description: Body is stout; head is triangular, clearly broader than neck; heat sensitive pits found laterally on snout. Dorsum is off-white or yellow, gray or light brown with irregular shaped patches of dark grayish-brown or blackish color, top series of blotches larger than blotches found on flank which are bordered by black. Venter is white or yellowish. Tail is short having dark yellow and black reticulations of irregular shape. It can grow up to 7-8 metres.

Conservation Status: IUCN Red List: Vulnerable (VU); IWPA, 1972: Schedule I, CITIES: Appendix II

Family Natricidae

 

  1. Cherrapunjee Keelback/Strange-tailed Keelback

Scientific Name: Hebius xenura (Wall, 1907)

Description: Body is slender, head is distinct from neck; eyes large with rounded pupils. Dorsal color is dark olive brown with paired series of reddish-orange, pale brown, yellow or white spots and adjacent spots connected by black crossbars. Venter is white or yellow with dark brown spots at the margins of ventrals. Length of head and body is approximately 66cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Buff-striped Keelback

Scientific Name: Amphiesma stolatum (Linnaeus, 1758)

Description: Body is slender, head is distinct from neck; eyes with rounded pupils. Dorsum is olive-grey to greenish grey. Two buff or yellowish-brown stripes run longitudinally from neck to end of the tail with white or red dots. Dark transverse bars present. Belly is glossy white or yellowish white. Length of head and body is approximately 80cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Eastern Keelback

Scientific Name: Herpetoreas platyceps (Blyth, 1854) 

Description: Body is slender; eyes with rounded pupils. Dorsum is dark grey, bronze- brown, reddish-brown or yellowish-brown. A dark band runs from snout to angle of jaw through eyes. Belly is off white or whitish orange. Length of head and body is approximately 88cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Checkered Keelback/ Asiatic Water Snake

Scientific Name: Fowlea piscator (Schneider 1799) 

Description: Body is stout; nostril directed towards upwards; eyes with rounded pupils. Dorsum is olive, green, yellow or light reddish brown with black spots arranged in 5-6 rows. Head brown with black stripe from eye to upper lip. Venter is white. Length of head and body is approximately 150cm.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule II; CITIES: Appendix III

 

 

 

Mildly Venomous

Family Colubridae

 

  1. Green Cat Snake

Scientific Name: Boiga cyanea (Duméril, Bibron & Duméril, 1854)

Description: Body is slender, compressed; head is triangular, large and distinct from neck; eyes large with vertical pupils. Dorsal color is uniform green and interstitial skin is black. In juveniles its coloration is reddish-brown except head which is of green color. Venter colour is greenish or yellowish white, may be unpatterned or with darker green spots. Length of head and body is approximately 187cm. It is mildly venomous, generally not harmful to humans.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Eastern Cat Snake/Eastern Gamma

Scientific Name: Boiga gocool (Gray, 1834)

Description: Body is slender, compressed; head is triangular, large and distinct from neck; eyes large with vertical pupils. Dorsal color is yellowish-brown or brown with series of distinct “T” or “Y” shaped marks with runs in pairs throughout the body length. An arrow shaped brown mark edged with black is present on head. Belly color is white with series of blackish-brown. Length of head and body is approximately 120cm. It is mildly venomous.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Many-spotted Cat Snake/ Large-spotted Cat Snake

Scientific Name: Boiga multomaculata (Boie, 1827)

Description: Body is slender, compressed; head is triangular, large and distinct from neck; eyes large with vertical pupils. Dorsal color is grayish-brown with asymmetrically arranged, large, oval shaped blackish or dark brown spots with white borders. An arrow shaped dark brown mark with black border and median gap present on the head. Belly is greyish-brown or whitish with brown spots. Length of head and body is approximately 99cm. It is mildly venomous.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Tawny Cat Snake

Scientific Name: Boiga ochracea (Theobald, 1868)

Description: Body is slender, compressed; head is triangular, large and distinct from neck; eyes large with vertical pupils. Dorsal color is reddish-brown, ochre or coral-red, poorly defined dark transverse line may be present. Venter colour is yellow to light brown. Length of head and body is approximately 110cm. It is mildly venomous.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Thai Cat Snake/ Eyed Cat Snake

Scientific Name: Boiga siamensis (Nutaphand, 1971)

Description: Body is slender, compressed; head is triangular, large and distinct from neck; eyes large with vertical pupils. Dorsal color is yellowish or greyish brown, finely speckled with dark brown. Series of dark brown spots or black spots or blotches present on vertebrae. Venter colour is yellowish white, speckled with brown. Length of head and body is approximately 160cm. It is mildly venomous.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

Family Homalopsidae

 

  1. Rainbow Mud Snake/Striped Water Snake

Scientific Name: Enhydris enhydris (Schneider, 1799)

Description: Body is thick, robust; head is small; snout obtusely rounded; eyes are with vertically elliptical pupil. Dorsal color is olive brown, greyish or metallic greenish with longitudinal stripes along the body. Two lateral stripes run along the body. Belly is yellowish white with series of black dots forming mid line along. Length of head and body is approximately 70cm. It is mildly venomous

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

Venomous

Family Natricidae

 

  1. Himalayan Keelback

Scientific Name: Rhabdophis himalayanus (Günther, 1864)

Description: Body is stout;head distinct from neck; eyes with rounded pupils. Dorsum is olive, olive-brown or dark brown. Two dorsolateral stripes orange-cream colour runs along the body. Stripes have orange or white spots which fade anteriorly. Neck has orange or red collar.A dark band runs from snout to angle of jaw through eyes. Belly is yellowish white which is darker towards tip. Length of head and body is approximately 125cm. It is a venomous snake.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Red-necked Keelback

Scientific Name: Rhabdophis subminiatus (Schlegel, 1837)

Description: Body is slender; head distinct from neck; eyes with rounded pupils. Dorsum is olive-brown or green with black and yellow reticulation pattern. Neck has yellow and red band. Belly is yellow. Length of head and body is approximately 130cm. It is a venomous snake.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

Family Elapidae

  1. Banded Krait

Scientific Name: Bungarus fasciatus (Schneider, 1801)

Description: Body is slender, triangular in cross-section. Dorsum body has alternate yellow, yellowish-brown and black broad bands of almost the same breadth. Head is black with an inverted “V” shaped yellow mark. Ventral side same as dorsal side. Length of head and body is approximately 225cm. It is a venomous snake.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule IV

 

  1. Greater Black Krait

Scientific Name: Bungarus niger (Wall, 1908)

Description: Body is slender, triangular in cross-section with shiny smooth scales. Dorsum is uniform black or bluish black without any band or marking. Belly color milky white or yellowish-white. Length of head and body is approximately 180cm. It is a venomous snake.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Lesser Black Krait

Scientific Name: Bungarus lividus (Cantor, 1839)

Description:  Morphologically it looks very close to Greater Black Krait (Bungarus niger). Both species are known for patternless uniform black body with yellowish underside. In B. lividus the vertebral scales are not much distinct than adjacent scales and significantly narrower than most of the Krait species. While in Great Black Krait they are significantly larger than adjacent scales and of hexagonal shape. It is a venomous snake.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule IV

 

  1. Monoclad Cobra

Scientific Name: Naja kaouthia (Lesson, 1831)

Description: Body is stout; head indistinct from body; neck capable of dilating into hood. Body color shows wide range of colors including light or dark brown, reddish-brown, black or grayish ting. Hood has an eye mark. Throat region on ventral side has black bands. Belly is cream coloured. Length of head and body is approximately 230cm. It is a venomous snake.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule II; CITIES: Appendix II

 

  1. Spectacled Cobra

Scientific Name: Naja naja (Linnaeus, 1758)

Description: Body is stout; head indistinct from body; neck capable of dilating into hood. Dorsum is greyish-brown, nrown-black or jet black. Can be easily identified by the presence of hood and the spectacle mark on the back of the hood, sometimes might be absent. Venter is white or cream coloured. Length of head and body is approximately 220cm. It is a venomous snake.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule II; CITIES: Appendix II

 

  1. King Cobra

Scientific Name: Ophiophagus hannah (Cantor, 1836) 

Description: Body very long, slender and covered with large size smooth scales; neck capable of dilating into hood.  Dorsum is dark brown, yellow, black or olive brown with pale yellow or orange bands I young that may or may not persist in adults. Venter is white or yellowish white with dark bands at throat. It can grow up to 19.19ft. It is a venomous snake.

Conservation Status: IUCN Red List: Vulnerable (VU); IWPA, 1972: Schedule II; CITIES: Appendix II

 

Family Viperidae

 

 

  1. Red-tailed Pit Viper/ Spot-tailed Pit Viper/ Keeled Headed Pit Vipe

Scientific Name: Trimeresurus erythrurus (Cantor, 1839)

Description: Body slender; head long, narrow, and distinct from neck. Dorsum is green or yellowish-green with interscale color black. A fine white line starts from posterior of eyes and runs along the last dorsal row till the base of tail. Belly color mostly yellowish-green or greenish white with darker color on edge. Length of head and body is approximately 105m. It is a venomous snake.

Conservation Status: IUCN Red List: Least Concern (LC); IWPA, 1972: Schedule II

 

  1. Russell’s Viper

Scientific Name: Daboia russelii (Shaw & Nodder, 1797)

Description: Body stout; head large; neck thin and pupil’s vertical. Dorsal colour is light or dark grayish-brown, reddish, orange or entirely gray occasionally. Black or brown oval spots arranged in three rows runs along the body axis. Head has inverted “V” mark. Venter white with crescent marks. Length of head and body is approximately 185m. It is a venomous snake.

Conservation Status: IUCN Red List: Not Evaluated (NE); IWPA, 1972: Schedule II; CITIES: Appendix III

Book

Yellow-speckled Wolf Snake


Book

Thai Cat Snake


Book

White-barred Kukri Snake


Book

Painted Bronzeback


Book

Copper-headed Trinket Snake ©Monish Kumar Thapa


Book

Red-necked Keelback ©Monish Kumar Thapa


Book

Banded Krait


Book

Burmese Python


Book

Checkered Keelback


Book

Chinese Rat Snake


Book

Monoclad Cobra


Book

Common Wolf Snake ©Monish Kumar Thapa


References

Ahmed, F., A. Das & S.K. Dutta (2009). Amphibians and Reptiles of northeast India - A Photographic Guide. Aaranyak, Guwahati, India

Daniel, J.C. (2002). The Book of Indian Reptiles and Amphibians. Bombay Natural History Society, Oxford University Press, Bombay, India.

 Das, I. (2002). A Photographic Guide to Snakes and other Reptiles of India. New Holand Publication, UK

Whitaker, R & A. Captain (2004). Snakes of India - The Field Guide. Draco Books, Chengalpet, Tamil Nadu, India

Websites

assambiodiversity.org

indiabiodiversity.org

inaturalist.org

indiansnakes.org