The file snake is not a protected animal. It is a rare non-venomous snake among the sea snakes. Its body length is between 60 cm and 1 meter. Its muscles are soft, its body is yellowish brown, and its surface has very fine granular scales.

The cardiovascular and respiratory physiology of the file snake is very suitable for life in water, Its hemoglobin oxygen delivery efficiency is particularly high, and the heartbeat during diving can be reduced to less than 1 beat per minute. Its incubation time in water can be as long as 5 hours, during which 13% of the breathing function is carried out through the skin. The tissue and scales of the file snake's lips seal the mouth tightly, and there is a salt-secreting gland in the lower jaw to share the heavy burden of excretion of salt by the kidneys.