Enhydrina schistosa, commonly known as the beaked sea snake, is a highly venomous species. Recognized for its unique snout and potent venom, it is one of the most medically important sea snakes encountered in its range. Its presence in coastal Indo-Pacific waters highlights its significance, as it is responsible for a substantial portion of sea snake bites and related fatalities globally.
Key Characteristics and Habitat
The beaked sea snake has a stout body, measuring 1 to 1.2 meters (3.3 to 4 feet) in length, though some individuals reach up to 1.5 meters (5 feet). Its coloration ranges from gray, olive, or brown, often with darker bands or blotches and a lighter underbelly. A distinctive “beaked” or hook-shaped snout, formed by an enlarged rostral scale, gives the snake its common name.
The tail of Enhydrina schistosa is laterally flattened and paddle-shaped, an adaptation that assists its movement through water. This species is found in coastal waters of the Indian Ocean and western Pacific Ocean, including the Persian Gulf, Bay of Bengal, and Southeast Asia. It prefers shallow coastal waters, estuaries, river mouths, and occasionally freshwater rivers, often inhabiting muddy or sandy substrates. The beaked sea snake primarily preys on fish, such as catfish and pufferfish, and shrimp, locating its victims by smell and touch in murky waters.
Understanding Its Venom and Bite
The venom of Enhydrina schistosa is highly potent, containing neurotoxins and myotoxins. Neurotoxins disrupt nerve function, leading to respiratory failure, while myotoxins cause rapid muscle damage and breakdown (rhabdomyolysis). As little as 1.5 milligrams can cause death in humans, making its venom several times more lethal than that of a cobra.
Symptoms of an Enhydrina schistosa bite can manifest within hours, or rapidly within 1-2 hours in severe cases. Initial signs include muscle pain, weakness, and drooping eyelids. As the venom progresses, severe symptoms develop, such as difficulty swallowing and speaking, paralysis of voluntary muscles, and kidney failure. Dark-colored urine indicates muscle breakdown.
Immediate medical attention is necessary following a beaked sea snake bite. While first aid measures like pressure immobilization may be considered, prompt transport to a medical facility is most important. There, specific antivenom can be administered to neutralize the venom’s effects, alongside supportive care such as pain management and respiratory support.