Black-headed Royal Snake ( Spalerosophis atriceps Fischer, 1885 )

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Name
Scientific Name: 
Spalerosophis atriceps (Fischer, 1885)
Regional Names: 
English: 
Diadem Snake
Rajasthani: 
Rajatbansi
Gujarati: 
રજવાડી સાપ
Photographs: 
Subadult form. Punjab
Distribution: 
Found in deserts and semi deserts of Northern-western India from Kutch (Gujarat) to non-Himalayan parts of Jammu & Kashmir. Also found in Nepal and Pakistan.
Family: 
Characteristics for identification: 

It bears two or three distinct forms in patterns in three life stages in which adults can be easily identified by having reddish-brown or orange color with more or less black patches in whole body.

Description: 

New born- 25-47cm.
Average length- 150cm. (5ft).
Maximum length- 200m.

Dorsal -
Body stout, robust and covered with less glossy scales. Lightly keeled oval shaped scales present mostly on the top dorsal of posterior side.
Adult: Color yellow, yellowish-brown or orange. various amount of blackish color patches present in irregular manner from neck to tail.
Subadult and Juveniles: Dorsal scales orange mixed with brown or yellow color mostly; series of same shaped patches present on the top of dorsal which have darker color than ground surface. Blackish scales also present in few places which become dominant in adult stage. These blackish scales absent in hatchlings.

Ventral -
Belly color pinkish-red or with blackish color patches arranged irregularly at few places. Subcaudal scales paired in zig-zag manner.

Head -
Head elongated, triangular and clearly broader than neck. Covered with fragmented shields. Large eyes have rounded pupil. There are two most common patterns in two life stages.
Adults: Head color blackish, bluish black or dark red color; white color present on upper lip few times.
Juveniles and newborns: Have totally different markings like an arrow; usually one dark and bent line joins eyes followed by arrow shaped marking which reaches to the end of the head or remain in the form of triangular spot, may or may not join with the curve joining eyes. Upper lips whitish.

Tail-
Long tail of same dorsal color with black patches, juveniles and subadults have irregular shape patterns or plain.

Scalation
Head: 
Rostral broader than high; supralabial 10-13; series of small subocular separates them from eyes; prefrontals broken into small scales unlike typical Colubrids; loreal 2, one behind the another; preocular 2; postocular 3 or 4; anterior temporals 3 or 4 of small size.
Dorsal: 
Lightly keeled scales in 27/29/31/33 at mid body, 2 or 4 less on neck, 19/21 on posterior body.
Ventral: 
216-250 (278 ventral found in a female from Gilgit); anal divided or undivided.
Sub Caudal: 
82-112; divided.
Habitat: 
Distributed in deserts, semi-deserts, degrading lands of its range. Found in wide range of elevations up to 6560ft. This species is confined in urban settlement of many parts of its range in North India and often seen at heights of buildings. Choose mounds, rodent holes, crevices etc. for roosting.
Natural History: 
Black-headed Royal Snake is a nocturnal species which can show activity at dim light of daytime also. Activity both terrestrial and climbing. Locomotion serpentine in moderate speed. Behavior alert but usually calm. On threatening it coils whole body and hiss loudly with pressure cooker whistle like sound and gives mock attacks. Oviparous. Mating begins from late winters to monsoon. New born seen during all monsoon months.
Diet: 
Feeds on rodents, birds, lizards, small mammals etc.
Threats: 
Killing due to misidentification and large size are intentional threats to this species. Roadkill mortality and loss of habitat (undisturbed dry lands) are additional causes. This species is exploited by West Indian snake charmers for display and under high demand for pet trade.
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