''Aipysurus fuscus'', commonly known as the dusky sea snake or Timor Reef snake, is a species of

sea snake Sea snakes, or coral reef snakes, are elapid snakes that inhabit marine environments for most or all of their lives. They belong to two subfamilies, Hydrophiinae and Laticaudinae. Hydrophiinae also includes Australasian terrestrial snakes, wher ...

in the family

Elapidae Elapidae (, commonly known as elapids ; grc, ἔλλοψ ''éllops'' "sea-fish") is a family of snakes characterized by their permanently erect fangs at the front of the mouth. Most elapids are venomous, with the exception of the genus Emydoceph ...

. It is found in the

Timor Sea The Timor Sea ( id, Laut Timor, pt, Mar de Timor, tet, Tasi Mane or ) is a relatively shallow sea bounded to the north by the island of Timor, to the east by the Arafura Sea, and to the south by Australia. The sea contains a number of reefs, ...

between

Australia Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, sma ...

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

and

East Timor East Timor (), also known as Timor-Leste (), officially the Democratic Republic of Timor-Leste, is an island country in Southeast Asia. It comprises the eastern half of the island of Timor, the exclave of Oecusse on the island's north-weste ...

and has been classified as

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

Description and taxonomy

''A. fuscus'' tends to be dark, colored purplish brown, brown, or blackish brown above. It occasionally has paler bands on the lower flanks. The center of each lateral scale is occasionally darker, giving the appearance of longitudinal striations. It is a member of the subfamily

Hydrophiinae Hydrophiinae is a subfamily of venomous snakes in the family Elapidae. It contains most sea snakes and many genera of venomous land snakes found in Australasia, such as the taipans (''Oxyuranus''), tiger snakes (''Notechis''), Pseudonaja, brown sn ...

, or marine elapid snakes. The

species name In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

of ''A. fuscus'' derives from the Latin term ''fuscus,'' which translates to "dusky" or "dark," in reference to the snake's coloration. The species is thought to not usually grow beyond in length, although substantially larger specimens have been found. It is thought to reach reproductive maturity after three or four years, have an average

generation time In population biology and demography, generation time is the average time between two consecutive generations in the lineages of a population. In human populations, generation time typically ranges from 22 to 33 years. Historians sometimes use this ...

of five years, and an average lifespan of ten.

Behavior and ecology

The snake is

venomous Venom or zootoxin is a type of toxin produced by an animal that is actively delivered through a wound by means of a bite, sting, or similar action. The toxin is delivered through a specially evolved ''venom apparatus'', such as fangs or a sti ...

. It is also

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

, or live-bearing. A 2006 study suggested that it was most closely related to '' Aipysurus laevis'', with which it has been documented as hybridizing. It has been recorded as feeding on fish eggs and

eel Eels are ray-finned fish belonging to the order Anguilliformes (), which consists of eight suborders, 19 families, 111 genera, and about 800 species. Eels undergo considerable development from the early larval stage to the eventual adult stage ...

s, as well as on

wrasse The wrasses are a family, Labridae, of marine fish, many of which are brightly colored. The family is large and diverse, with over 600 species in 81 genera, which are divided into 9 subgroups or tribes. They are typically small, most of them le ...

s and

gobies Gobiidae or gobies is a family of bony fish in the order Gobiiformes, one of the largest fish families comprising more than 2,000 species in more than 200 genera. Most of gobiid fish are relatively small, typically less than in length, and the ...

. The species has a shallow depth range, generally from the surface down to .

Habitat and distribution

''A. fuscus'' primarily inhabits reefs in shallow marine habitats. It has occasionally been recorded at depths of up to . The only reliable reports of this species in the wild are from the

, from the reefs of Ashmore,

Cartier Cartier may refer to: People * Cartier (surname), a surname (including a list of people with the name) * Cartier Martin (born 1984), American basketball player Places * Cartier Island, an island north-west of Australia that is part of Australia' ...

and Hibernia of the Ashmore and Cartier Islands, and the reefs of Scott and Seringapatam. Not more than five subpopulations are thought to exist, and the overall population is severely fragmented. The

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

was reported as being collected off the coast of

Sulawesi Sulawesi (), also known as Celebes (), is an island in Indonesia. One of the four Greater Sunda Islands, and the world's eleventh-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Ar ...

, but this location has been called into question. This, combined with the observation that the species only uses a small depth range, has led the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

to conclude that the snake has a range of less than .

Conservation status

Catch rates for the species declined drastically between 1998 and 2007, in which year no specimens were found. The estimated decline in the population of ''A. fuscus'' is at least 70%. The specific threats to this snake are poorly understood, but they are suspected to have been affected by

coral bleaching Coral bleaching is the process when corals become white due to various stressors, such as changes in temperature, light, or nutrients. Bleaching occurs when coral polyps expel the zooxanthellae (dinoflagellates that are commonly referred to as alg ...

and general decreases in the health of their ecosystems. These data have led to its being classified as

. Ashmore reef, one of five inhabited by ''A. fuscus'', has been a nature reserve since 1983.

References

{{Taxonbar, from=Q2435014 fuscus Reptiles of the Indian Ocean Timor Sea Snakes of Australia Reptiles of Timor Reptiles of Indonesia Marine fauna of Oceania Marine fauna of Southeast Asia Endangered fauna of Asia Endangered fauna of Oceania Reptiles described in 1837 Species endangered by habitat fragmentation Taxa named by Johann Jakob von Tschudi