Indian Sand Boa
Eryx johnii
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Boidae
Genus: Eryx
Species: E. johnii
Conservation Status: This species of sand boa has seen a recent population decline, mostly due to its use in folklore medicinal purposes. It is classified as 'near threatened', and receives special protection under the Indian government's wildlife protection act.
Natural History: The Indian Sand Boa is the world’s largest species of ‘Sand Boa’ (subfamily Erycinae). These large robust fossorial snakes hail from dry semi-arid and desert regions of Iran, Afghanistan, Pakistan, India, and Nepal. These snakes are rarely seen in their native range, owing much of their scarcity to the remoteness and generally un-developed nature of their natural range and the secretive lifestyle they lead. These animals prefer sandy or very loose soil; they will burrow through such material and often rest with just a small portion of their head and upturned eyes exposed, waiting patiently for prey to wander past their ambush site. The Indian Sand Boa then explodes in sudden and violent movement to grasp their prey and then either constricts or pins it to a flat surface. The tiny rounded scales help the boa by providing traction and also allowing them to glide smoothly through loose soil. In areas where the ground is less cooperative they will sometimes seek temporary shelter under rocks, fallen trees and even matted vegetation and human created debris. Like most sand boas johnii are short, stout heavy bodied animals with small eyes and a blunt wedge shaped head, the Indian sand boa typically measures 26-30” upon adulthood but specimens reaching 36” have been reported.
Care in Captivity: Despite the limited availability of this species in U.S. collections, these snakes are no more difficult to care for than the ubiquitous Kenyan sand boa (G.colubrinus). Adults may be maintained in naturalistic habitats with deep layers of loose sandy substrate or even size appropriate rack tubs with deep layers of loose aspen shavings or sani-chips. They do require a thermal gradient and I utilize thermostatically controlled flexwatt to heat my tubs. The target ‘hot spot’ is the high 80’s to low 90’s with a cool side dropping into the high 70’s. These animals do best when kept consistently warm, however I do expose my snakes to 5 degree temperature drop at night with no ill effects. I utilize low flat pieces of clay planters as hides, but generally the snakes can be seen lying under the substrate with the head exposed looking for their next meal. I use heavy crock water bowls to prevent the burrowing snakes from tipping them in their enclosure while exploring. Some newborn sand boas may be reluctant to feed at first, under most circumstances I can provide the neonates with a couple inches of sand and then take a frozen/thawed pinky (well dried) in a pair of forceps and gently move it across the surface near where the animal is lying in wait. In all but the most extreme cases this combination of environmental factors and natural prey behavior creates a tremendous feed response and you may be startled with how aggressively your normally calm sand boa engages the offered prey. Like most sand boas there is some sexual dimorphism with males being typically smaller than females.
Captive Reproduction: Indian sand boas hail from regions of the world that are fairly consistent with seasonal temperature, that being said some keepers provide little to no environmental stimulus and still report breeding success. I prefer to provide a combination of two environmental triggers, I start with a short fast of two weeks in early fall, then reduce the temperature produced by the heat tape to the low 80’s for a period of 3-4 weeks. During this time no prey is offered and the normal fluctuation of ambient temperature is allowed to continue. The animals are then slowly warmed back up over a period of seven to ten days and I begin lightly misting the tubs every evening for five to seven days while returning to a slightly increased feeding schedule. I then begin pairing animals every other evening and monitoring for any courtship behavior. Once several successful copulations are witnessed, or the animals seem no longer interested, I stop pairing them. If the female is developing fertilized embryo she will gain noticeable mass over the next 3-4.5 months and will usually stop taking food in the weeks leading up to birth. The boa will typically birth at night, dropping 8-14 surprisingly large neonates over a period of several hours. The offspring are separated, housed in hatchling tubs with a deep enough layer of sani-chips to allow natural burrowing behavior and their care is no more difficult than that of the adult animals.