Most active during twilight hours, the javelin sand boa usually lies hidden under sand or in cracks in the soil during the day and hunts at dusk and dawn (4) (5) (7). This species typically burrows through sand and soil (1) (4) (7), but when travelling on the surface it moves with a wave-like motion (5).
The javelin sand boa usually catches its prey by ambushing it, lying in wait under the sand or soil with the eyes and nose just above the surface to detect passing prey. When its victim comes close enough, the snake attacks it with surprising speed, and kills it by constriction (4) (6) (7). Small prey items may also be swallowed alive (4). The javelin sand boa is also thought to search actively for prey, for example by entering rodent burrows (2) (4) (11).
The diet of the javelin sand boa is thought to consist mainly of small mammals, as well as some lizards and birds (4) (7) (11), and occasionally invertebrates such as slugs (4) (6) (7). Unlike most snakes, the javelin sand boa has been observed using its tongue to lap up water (7). When threatened by a potential predator, the javelin sand boa may use its tail to deflect attention away from its vulnerable head region (4).
The javelin sand boa is ovoviviparous, giving birth to live young that have hatched from eggs within the female’s body (1) (2) (4) (7) (9). In captivity, Eryx species mate in the spring and early summer, with development of the young inside the female taking around four to five months (1) (4). The javelin sand boa usually gives birth to 5 to 20 offspring at a time (1) (2) (6), between August and September (1), with each of the young measuring about 14 to 20 centimetres in length and weighing around 8 grams (2).
Like other sand boas, the javelin sand boa is able to tolerate quite wide extremes of temperature and long periods of drought (4). This species becomes inactive between October and March or April (1), when it is likely to hibernate in loose sand, rodent burrows, crevices or beneath rocks (4).