Aipysurus duboisii or Dubois' seasnake is a species of sea snake. Their habitat includes Papua New Guinea

Papua New Guinea

Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...

, New Caledonia

New Caledonia

New Caledonia is a special collectivity of France located in the southwest Pacific Ocean, east of Australia and about from Metropolitan France. The archipelago, part of the Melanesia subregion, includes the main island of Grande Terre, the Loyalty Islands, the Belep archipelago, the Isle of...

 and the northern, eastern and western coastal areas of Australia, that is the Coral Sea

Coral Sea

The Coral Sea is a marginal sea off the northeast coast of Australia. It is bounded in the west by the east coast of Queensland, thereby including the Great Barrier Reef, in the east by Vanuatu and by New Caledonia, and in the north approximately by the southern extremity of the Solomon Islands...

, Arafura Sea

Arafura Sea

The Arafura Sea lies west of the Pacific Ocean overlying the continental shelf between Australia and New Guinea.-Geography:The Arafura Sea is bordered by Torres Strait and through that the Coral Sea to the east, the Gulf of Carpentaria to the south, the Timor Sea to the west and the Banda and Ceram...

, Timor Sea

Timor Sea

The Timor Sea is a relatively shallow sea bounded to the north by the island of Timor, to the east by the Arafura Sea, to the south by Australia and to the west by the Indian Ocean....

 and Indian Ocean

Indian Ocean

The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...

. They live at depths up to 80 meters in coral reef

Coral reef

Coral reefs are underwater structures made from calcium carbonate secreted by corals. Coral reefs are colonies of tiny living animals found in marine waters that contain few nutrients. Most coral reefs are built from stony corals, which in turn consist of polyps that cluster in groups. The polyps...

 flats, sandy and silt

Silt

Silt is granular material of a size somewhere between sand and clay whose mineral origin is quartz and feldspar. Silt may occur as a soil or as suspended sediment in a surface water body...

y sediments which contain seaweed

Seaweed

Seaweed is a loose, colloquial term encompassing macroscopic, multicellular, benthic marine algae. The term includes some members of the red, brown and green algae...

, invertebrates and corals or sponges that can serve as shelter. These snakes feed on moray eel

Moray eel

Moray eels are cosmopolitan eels of the family Muraenidae. The approximately 200 species in 15 genera are almost exclusively marine, but several species are regularly seen in brackish water and a few, for example the freshwater moray can sometimes be found in freshwater...

s and various fish that live on the seafloor, up to 7 cm in size. They are viviparous, giving birth to live young rather than laying eggs. They have medium aggressiveness, i.e. will bite if provoked, but not spontaneously. The fangs are 1.8 mm long, which are relatively short for a snake, and the venom yield is 0.43 mg. Aipysurus duboisii is a crepuscular

Crepuscular

Crepuscular animals are those that are active primarily during twilight, that is during dawn and dusk. The word is derived from the Latin word crepusculum, meaning "twilight." Crepuscular is, thus, in contrast with diurnal and nocturnal behavior. Crepuscular animals may also be active on a bright...

 species, meaning that they are most active at dawn

Dawn

Dawn is the time that marks the beginning of the twilight before sunrise. It is recognized by the presence of weak sunlight, while the sun itself is still below the horizon...

 and dusk

Dusk

Dusk is the beginning of darkness in the evening, and occurs after twilight, when the sky generally remains bright and blue. Civil dusk is when the earth has rotated enough that the center of the sun is at 6° below the local horizon...

.

Description

Adults grow up to 148 cm in length but usually to around 80 cm. Their head is slightly wider than their body with nostril

Nostril

A nostril is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation...

s on its upper part and nasals contacting each other. Eyes are separated from supralabial scales

Supralabial scales

In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scale . The term labial originates from Labium , which refers to any lip-like structure...

 by a row of large subocular scales. Dorsal scales are usually smooth, but sometimes have a small keel or small knobs. Individuals vary significantly in color and its body patterns. The tail is relatively long; the chin and throat have lighter color than rest of the body.

Toxicity

The acute toxicity

Acute toxicity

Acute toxicity describes the adverse effects of a substance that result either from a single exposure or from multiple exposures in a short space of time...

 of snake venom

Snake venom

Snake venom is highly modified saliva that is produced by special glands of certain species of snakes. The glands which secrete the zootoxin are a modification of the parotid salivary gland of other vertebrates, and are usually situated on each side of the head below and behind the eye,...

 is conventionally tested on laboratory animals and is evaluated in terms of the median lethal dose (LD₅₀), that is, the dose required to kill half the members of a tested population divided by the weight of the tested animal. The LD₅₀ depends on the animal. Rabbits are about twice as sensitive to sea snake venom as mice, and fish and frogs are even more susceptible. The LD₅₀ for subcutaneous injection

Subcutaneous injection

A subcutaneous injection is administered as a bolus into the subcutis, the layer of skin directly below the dermis and epidermis, collectively referred to as the...

 of A. duboisii venom into mice is 0.044 mg/kg of body weight. This makes A. duboisii the most poisonous sea snake, and the third most poisonous snake after the Inland Taipan (Oxyuranus microlepidotus, LD₅₀=0.025 mg/kg) and the Eastern Brown Snake

Eastern brown snake

The eastern brown snake , often referred to as the common brown snake, is a species of genus Pseudonaja. This snake is considered the second most venomous land snake based on its value in mice. It is native to Australia, New Guinea and Indonesia.-Description:Adult eastern brown snakes are highly...

(Pseudonaja textilis, LD₅₀=0.0365 mg/kg).