Elapidae
Slender-necked Sea Snake
VenomousHydrophis melanocephalus
The Slender-necked Sea Snake (Hydrophis melanocephalus) is a venomous snake in the Elapidae family, recorded in 8 countries.
If you are bitten
This is a venomous snake. Treat any bite as a medical emergency: stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to emergency care immediately. Do not apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call your local emergency number or poison center.
- Family
- Elapidae
- Danger
- high
About the Slender-necked Sea Snake
Hydrophis melanocephalus, commonly known as the slender-necked sea snake, is a species of venomous sea snake in the family Elapidae.
Geographic range
South China Sea, Jeju Island, Korea.
Japan (Ryūkyū, Hokkaidō, Kochi).
Coasts of Taiwan and Guangdong northward to Zhejiang (China).
Australia (North Territory?, Western Australia), New Guinea.
Description
Head black dorsally and ventrally, with a yellowish bar on the prefrontals, and with a yellowish streak behind the eye on the postocular and upper portion of last upper labial. Anterior part of body black dorsally and ventrally, with yellow crossbars on the dorsum. Posterior part of body olive dorsally and yellow ventrally, with black rings, which are broader on the dorsum.
The type specimen, a female, is 107 cm (42 in) in total length, with a tail 8.5 cm (3+1⁄4 in) long.
All dorsal scales rhomboidal and imbricate (overlapping). Dorsal scales on neck smooth, arranged in 25 rows. Dorsal scales on body with a short keel or small tubercle, in 35 rows. Ventrals 329.
The head very small and the body long, very slender anteriorly. Rostral slightly broader than deep. Frontal nearly twice as long as broad, as long as its distance from the rostral, slightly shorter than the parietals. One preocular and one postocular. A single anterior temporal. Seven or eight upper labials, second largest and in contact with the prefrontal, third and fourth (or third, fourth, and fifth) entering the eye. There are two pairs of small chin shields, in contact with each other. The tail is laterally flattened and oar-like.
Adapted from Wikipedia, available under CC BY-SA.
Frequently asked: Slender-necked Sea Snake
- Is the Slender-necked Sea Snake venomous?
- Yes. The Slender-necked Sea Snake (Hydrophis melanocephalus) is venomous and belongs to the Elapidae family (cobra, mamba, coral or sea snake). Its bite is considered high risk to people. Treat any bite as a medical emergency.
- Is the Slender-necked Sea Snake poisonous?
- Snakes are venomous, not poisonous. "Poisonous" means harmful to eat or touch; "venomous" means injecting toxins through a bite. The Slender-necked Sea Snake is venomous, delivering venom through a bite.
- Is the Slender-necked Sea Snake dangerous?
- This is a venomous snake. Treat any bite as a medical emergency: stay calm, keep the bitten limb still and roughly level with the heart, remove rings and tight clothing, and get to emergency care immediately. Do not apply a tourniquet, cut the wound, apply ice, or try to suck out venom. Call your local emergency number or poison center.
- Where does the Slender-necked Sea Snake live?
- The Slender-necked Sea Snake has verified records in 8 countries, including Japan, Australia, Chinese Taipei. See the distribution section below for its full range.
If you are bitten by the Slender-necked Sea Snake
Do
- Get away from the snake and stay calm. Most bites worsen when people panic or try again to handle the snake.
- Call 911 or Poison Control (1-800-222-1222) right away. Antivenom works best when given early.
- Note the time of the bite and, from a safe distance, the snake's color and pattern, a phone photo is enough. Do not chase it.
- Keep the bitten limb still and at roughly heart level. Sit or lie down and limit movement.
- Remove rings, watches, and tight clothing near the bite before swelling starts.
- Gently wash the bite with soap and water and cover it with a clean, dry dressing.
Do not
- Do not cut the wound or try to suck out the venom.
- Do not apply a tourniquet or ice.
- Do not drink alcohol or caffeine.
- Do not take aspirin or ibuprofen, they can worsen bleeding. Acetaminophen is safer for pain.
- Do not try to catch or kill the snake. A dead snake can still bite by reflex.
First-aid guidance adapted from the U.S. Centers for Disease Control and Prevention (CDC NIOSH), Venomous Snakes. Educational only; always follow the instructions of emergency responders.
Where it is found
More Elapidae snakes
Yellow-bellied Sea SnakeHydrophis platurus
Olive-headed Sea SnakeHydrophis major
Beaked Sea SnakeHydrophis schistosus
Elegant Sea SnakeHydrophis elegans
Slender-necked Sea SnakeHydrophis coggeri
Spine-bellied Sea SnakeHydrophis curtus
Horned Sea SnakeHydrophis peronii
Persian Gulf Sea SnakeHydrophis lapemoides
Classification
How scientists group this snake, from the broadest category down to the exact species. Each step narrows to its closest relatives.
Keep learning
- Are Snakes Dangerous? The Real Risk, in PerspectiveMost snakes are harmless and avoid people. Here is the honest picture of snakebite risk worldwide and how to lower your own.
- Snakebite First Aid: What to Do (and What Never to Do)A clear, CDC-based guide to snakebite first aid: the steps that help, the popular myths that hurt, and how to tell a serious bite from a minor one.
- Venomous vs Nonvenomous: How to Tell the DifferenceThe folk rules for telling venomous snakes apart, where each one fails, and why location-based identification beats guessing by sight.
- What to Do If You Find a SnakeFound a snake at home or on a trail? Here is how to stay calm, give it space, identify it safely, and know when to call a professional.
Distribution from GBIF & iNaturalist. Venom status per CDC. Background: Wikipedia. Informational only. Never handle a snake to identify it.