Rat Snake (Ptyas mucosus)
English - Oriental Rat snake, Rat Snake | Hindi- Ghoda-Pachad | Marathi- Dhaman
Distribution - All over India.
Status - Very common.
Length- This is the largest Colubrid of India. General length is 7ft approx but can grow up to 350cm(11.6ft).
Dorsal body- - Body slender with shiny scales that are smooth and keeled. Keeled scales present on 4-8 top most rows mostly on the posterior body. Regular black, yellow and white band like markings present on the whole body according to the color of the dorsal body. These black colored patterns become net-Like on tail side and much clear than the mid body. Dorsal body color varies from jet black (Central India and parts of North-East), greenish black, dark brown, light brown, olive brown or black etc. Sometimes black colored specimens donít have any patterns so appear like Cobra.
Ventral body- Belly color also depends on dorsal body color from pale yellow or white mixed with green, brown, gray, yellow etc. sometimes dark color patches exist on the whole ventral side. Subcaudal scales paired in a zig-zag manner and ends with a pointed tip.
Head-Head pointed with shiny smooth scales, clearly broader than the neck. Between two lip scales, there is a presence of a blackish color border. The eyes are large eyes and have a rounded pupil. Tongue color purplish-black with darker color on the front side.
Tail- Long tail typically like other tree snakes with a pointed tip. Blackish reticulations present on the whole posterior body including the tail.
Key characters for identification-
Look alikes- Adults looks like Spactacled Cobra, Monocled Cobra, King Cobra, Indo-Chinese Rat snake, Chekered Keelback; Juveniles looks like Banded Racer, Chekered keelback etc.
- Very long body with dark color patterns on the whole body.
- Many times people recognize Rat snake by its head broader than neck.
Head- - 8 Supralabials; 4th & 5th touches eyes; 1 Preocular; 1 pre Sub-ocular; Loreal 2-4 but 3 is most common; 2 Postocular; Temporals 2+2.
Dorsal- Scales smooth with 17/18/19 in front body, 16/17 in mid body and 14 on posterior body found.
Ventral- 190-213; Anal divided.
Subcaudal- -98-146; divided.
Behavior- Rat snake is a diurnal species and is active only at day time; remains hidden in dark and silent places like rat holes, termite mounds, wood caves, under rocks, etc. during night time. Lives in almost all kinds of habitat due to its tendency to survive in tough conditions. Prefers wet surroundings during summer (shows semi aquatic behavior few times), while dry during monsoon. Habitats include gardens, agricultural lands, termite mounds, under heavy rocks, caves, dense dry leaves, wood caves, dense forests, piles of brick, wood, rock, dump, scrap and grain storage etc.
Very fast (one of the fastest terrestrial snake of the Indian subcontinent) and alert species. This makes them an active hunter and one of the fittest snake to survive in the toughest conditions. It is a very good climber and can creep very fast even on trees and heights. On threatening can growl like an angry dog and inflates its forebody to look bigger.
Feed on a variety of prey mostly on rodents and toads also feeds upon birds, small mammals, other snakes, all kind of lizards, eggs sometimes.
Reproduction - Mating period of Rat Snake starts from early winter to next yearís late monsoon. In short it reproduces for the whole year. Female lays a clutch of 8-26 eggs.
Rat snake is one the 3 most common snakes (other two being Chekered Keelback and Cobra). Human habitat especially gardens, grain storages, rat holes and other dry dark places attract this species due to presence of its shelter and prey. Other hiding places includes all kind of narrow and dark places inside houses, trees and bushes. In rescues it is found in almost all places inside houses even on 5th floor.
It is a totally harmless & non venomous species but due to very large size it is fascinating to ordinary human. Rat snake is one of the toughest species to survive in new places but not always. Its release can be done near rescue site if people allow this after letting them know about its behavior, sometimes they donít allow such huge snake or the rescue siteís location is found to be exclusively urban without any vegetation so release in new place should be done with proper knowledge about the new area. Juveniles should not be relocated strictly but adults can be released at day time near any agricultural land or forest with proper water supply and shelter in the area.