What are Blind Snakes

Blind snakes are small snakes with vestigial eyes that consist only of black spots beneath the scales on the head.  They have fewer than 40 mid-body scale rows and the scales are smooth and shiny, so they look like worms.  They are burrowers so they don’t need eyes and their small mouths are tucked back behind their shovel-like snouts which must help to keep the dirt out.  The tail is short and ends in a short spine.  The biggest blind snake reaches lengths of 60 cm but the average is much smaller and some are only 10 cm long which makes it even easier to mistake them for worms.  Another unusual characteristic of blind snakes is the lack of teeth on the lower jaw.

There are  two other small families of closely related blind snakes, the  Anomalepidae (fifteen species of primitive South American blind snakes)   and the  Leptotyphlopidae (90 species of thread snakes, found in Africa, Asia and the Americas).  The three families together form the infraorder Scolecophidia.   The typhlopids are the most numerous and widespread, being found in tropical and subtropical regions of Africa, Asia, Australia and the Americas.  There are over 200 described species of typhlopids but probably many more to be discovered due to their cryptic life style.

Blind snakes are nonvenomous and totally harmless.   They feed on ants and termites, especially the larvae and pupae,  and the distribution of each species is related to  the distribution of its primary prey species. They have an efficient way of eating where the toothed maxillae move in and out of the mouth in a raking motion which allows the consumption of large numbers of prey in a short period.   

Blind snakes are part of the food chain and their main defense is to burrow and stay out of the way of predators.  They are able to emit an unpleasant odor from anal glands. When grabbed, they thrash wildly, defecate and stab the offender with their tail spine.  Most of their lives are spent underground but sometimes they move around the surface at night, especially after summer rains. 

Blind snakes are sometimes found in groups.  These groups appear to be feeding groups rather than reproductive as they consist of both juveniles and adults.  Instead it appears that they are tolerant of each other and may all end up in the same place such as a termite mound where there is plenty of food.

Like most snakes, most of these little animals lay eggs.  However one unusual species, Ramphotyphlops brahminus, consists of an entirely female population that reproduces by parthenogenesis.  Species that live in subtropical climates probably mate in spring and bring off clutches of eggs in the summer.  Tropical species may reproduce all year.  Clutch and egg size is variable but in general, the smaller the species, the smaller the eggs and the fewer in a clutch. 

There is still much to be learned about blind snakes.  They are not important economically and are so small and cryptic that most people never see them.  Or if they do, they think they are seeing a worm.  But under the shiny worm-like skin is a backbone and the body of squamate reptile, suborder serpentes.

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