Ornate Sea Snake ( Hydrophis ornatus Gray, 1842 )

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Scientific Name: 
Hydrophis ornatus (Gray, 1842)
Regional Names: 
Ornate Reef Sea Snake
Found in all coasts of India from Gujarat to Sea. However it is uncommon in western coast and far northern coast of east India. Also found in Australia, China, Indonesia, Iran, Japan, Malaysia, Myanmar, New Caledonia, New Guinea, Oman, Pakistan, Philippines, Solomon Islands, Sri Lanka, India, Taiwan, Thailand, UAE and Vietnam.
Venom Type: 
Characteristics for identification: 

Morphologically it can be identified by checking rhomboidal bars or bands with narrower interspace of light color and light color belly. However it looks close to other Sea Snakes of genus Hydrophis and should be identified by scale counting. 


New born- 19-34cm.
Average length- 60cm.
Maximum length- 115cm.
Males grow larger than females.

Body -
Robust, stout, not elongate and its greatest diameter on middle and posterior is twice of neck. Dorsal grey or olive with yellowish-white belly. Dark rhomboidal spots or bars found dorsally which are separated by narrow interspace (narrower than bars) of lighter color. In most of the individuals these spots or bars may end on side or remain tapered and faint in belly. Tail compressed and oar-like with faint but usually visible markings.

Head -
Head large, broad and slightly broader than neck. Color olive green or grey with yellow-white markings mainly of snout and side. Eyes have rounded pupil.

7-8 supralabial, 2nd usually in contact with prefrontal, 3rd & 4th in contact with eyes; 1 preocular, 2-3 postocular; 2 anterior temporal.
28-37 (Male), 31-45 (Female) rows around the neck, 33-45 (Male), 39-55 (Female) around the mid-body with 4-12 increase; posterior scales more of less hexagonal, as broad as or broader than long, subimbricate or juxtaposed central tubercle or short keel.
209-260 (male), 236-312 (female), distinct, twice as broad as the adjacent dorsal scales, narrow posteriorly.
Lives in coral reefs, esturies and inshore waters.
Natural History: 
One of the active swimmer among coral reefs and estuaries. One of the most aggressive Sea Snake and can bite on mishandling. Usually helpless on ground. Viviparous. Female directly gives birth to 2-5 individuals of relatively larger size.
Feeds on eels and small fishes.
This is one of the most aggressive and one of the most frequently encountered Sea Snake in fishing ad other coastal activities. There are some regular venomous bite records due to this species and deaths possible if taken lightly.
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