Rhabdophis subminiatus

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Rhabdophis subminiatus
Siamese Red-necked keelback, Na Nong Tum, Chum Phae District, Khon Kaen, Thailand imported from iNaturalist photo 447504091.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Genus: Rhabdophis
Species:
R. subminiatus
Binomial name
Rhabdophis subminiatus
(Schlegel, 1837)
Synonyms [2]

Rhabdophis subminiatus, commonly called the red-necked keelback or red-necked keelback snake, is a species of venomous snake in the subfamily Natricinae of the family Colubridae. The species is endemic to Asia. Unusual for colubrids, it is also poisonous.

Contents

Description

Rhabdophis subminiatus has a greenish hue with red and yellow regions near the head. It grows to 70 to 90 cm (27.5 to 35.5 in) in total length (including tail). Female is much larger than male, mating behavior multiple males may swarm a single female. [3]

Rhabdophis siamensis 88137872.jpg
Juvenile
Siamese Red-necked keelback, Thma Bang, Kaoh Kong, Cambodia imported from iNaturalist photo 102031769 (cropped).jpg
Adult

Habitat and diet

The red-necked keelback generally lives near ponds, where it consumes frogs and fish. [4]

Snakebite and venom

In Nam Cat Tien National Park, South Vietnam. Red-necked keelback (Rhabdophis subminiatus).jpg
In Nam Cat Tien National Park, South Vietnam.

Rhabdophis subminiatus is a rear-fanged species and was previously thought to be harmless. However, following one fatal and several near-fatal envenomations, the toxicity of its venom was investigated. As a result, it has recently been reclassified as a dangerous species. Rear-fanged snakes need to bite and hold on, or repeatedly bite, to have any effect on humans. A chewing action facilitates envenomation, as the venom ducts open to fangs that are externally grooved (not hollow) and are posterior in the oral cavity. R. subminiatus has enlarged and ungrooved teeth. The species has two enlarged teeth in the back of the jaw. Located in the upper jaw is a gland known as Duvernoy's gland, which produces an extremely venomous secretion. [4]

Symptoms caused by venom

Extraction of venom from the red-necked keelback Rhabdophis subminiatus.png
Extraction of venom from the red-necked keelback
Eating a frog Siamese Red-necked keelback, Na Nong Tum, Chum Phae District, Khon Kaen, Thailand imported from iNaturalist photo 447503916.jpg
Eating a frog

When the snake bites, the salivary venom mixture is not injected, but it flows into the punctures produced by the upper jaw's rear teeth, which can penetrate the skin of humans. The venom from R. subminiatus has been responsible for internal hemorrhaging, including hemorrhaging of the brain, as well as nausea, coagulopathy, and even disseminated intravascular coagulation. Also, when the venom was tested on animals, kidney failure was reported. Caution should be taken when dealing with patients who have been bitten by the red-necked keelback snake. No further injury such as injections should be used because this may cause excessive bleeding in the bite victim. Although most bites of humans from R. subminiatus are involved with the front teeth and do not cause adverse effects, rare bites from the rear fangs can be lethal. [5] Studies in mice on the biological activity of the venom of the red-necked keel-back snake, Rhabdophis subminiatus, showed that the venom contained a potent Factor X activator and had intense defibrinogenating activity; the overall proteolytic activity of the venom was low, and this correlated well with its negligible fibrinogenolytic and fibrinolytic activities. Only one antivenom tested was shown to have weak neutralizing activity against the venom in mice. This species of snake has recently been added to the schedule of the Dangerous Wild Animals Act, 1976.[ citation needed ]

Etymology

Red-necked Keelback (Rhabdophis subminiatus) Hong Bo You She 9.jpg

The specific name subminiatus refers to the typical reddish coloration ("miniatus" = "scarlet, vermilion" [6] ), which may be limited to the neck, or more extensive (e.g., photo at left). The subspecific name, helleri, is in honor of American zoologist Edmund Heller. [7]

Geographic range

The red-necked keelback can be found in: [2]

Related Research Articles

<span class="mw-page-title-main">King cobra</span> Group of venomous snakes from Asia

The king cobra is a species complex of snakes endemic to Asia. With an average of 3.18 to 4 m and a record length of 5.85 m (19.2 ft), it is the world's longest venomous snake and among the heaviest. Under the genus Ophiophagus, it is not phylogenetically a true cobra despite its common name and some resemblance. Spanning from the Indian Subcontinent through Southeastern Asia to Southern China, the king cobra is widely distributed albeit not commonly seen.

<span class="mw-page-title-main">Colubridae</span> Family of snakes

Colubridae is a family of snakes. With 249 genera, it is the largest snake family. The earliest fossil species of the family date back to the Late Eocene epoch, with earlier origins suspected. Colubrid snakes are found on every continent except Antarctica.

<span class="mw-page-title-main">Snake venom</span> Highly modified saliva containing zootoxins

Snake venom is a highly toxic saliva containing zootoxins that facilitates in the immobilization and digestion of prey. This also provides defense against threats. Snake venom is usually injected by unique fangs during a bite, though some species are also able to spit venom.

<span class="mw-page-title-main">Boomslang</span> Species of snake

The boomslang is a highly venomous snake in the family Colubridae. The species is native to Sub-Saharan Africa.

<span class="mw-page-title-main">Envenomation</span> Process of venom injection

Envenomation is the process by which venom is injected by the bite or sting of a venomous animal.

<span class="mw-page-title-main">Red-bellied black snake</span> Venomous snake native to eastern Australia

The red-bellied black snake is a species of venomous snake in the family Elapidae, indigenous to Australia. Originally described by George Shaw in 1794 as a species new to science, it is one of eastern Australia's most commonly encountered snakes. Averaging around 1.25 m in length, it has glossy black upperparts, bright red or orange flanks, and a pink or dull red belly. It is not aggressive and generally retreats from human encounters, but will defend itself if provoked. Although its venom can cause significant illness, no deaths have been recorded from its bite, which is less venomous than other Australian elapid snakes. The venom contains neurotoxins, myotoxins, and coagulants and has haemolytic properties. Victims can also lose their sense of smell.

<span class="mw-page-title-main">Venomous snake</span> Species of the suborder Serpentes that produce venom

Venomous snakes are species of the suborder Serpentes that are capable of producing venom, which they use for killing prey, for defense, and to assist with digestion of their prey. The venom is typically delivered by injection using hollow or grooved fangs, although some venomous snakes lack well-developed fangs. Common venomous snakes include the families Elapidae, Viperidae, Atractaspididae, and some of the Colubridae. The toxicity of venom is mainly indicated by murine LD50, while multiple factors are considered to judge the potential danger to humans. Other important factors for risk assessment include the likelihood that a snake will bite, the quantity of venom delivered with the bite, the efficiency of the delivery mechanism, and the location of a bite on the body of the victim. Snake venom may have both neurotoxic and hemotoxic properties. There are about 600 venomous snake species in the world.

<span class="mw-page-title-main">Ring-necked snake</span> Species of snake

Diadophis punctatus, commonly known as the ring-necked snake or ringneck snake, is a rather small, harmless species of colubrid snake found throughout much of the United States, as well as south in Central Mexico and as far north as Quebec, Canada. Ring-necked snakes are generally fossorial and somewhat secretive, by nature, and, as a nocturnal species, are rarely seen during the daytime. These snakes are believed to be fairly abundant throughout most of their range, though no scientific evaluation supports this hypothesis. Scientific research is lacking for the species, despite their apparently common status, and more in-depth investigations are greatly needed. It is the only species within the genus Diadophis and, currently, 14 subspecies are identified, though many herpetologists question the morphologically-based classifications.

<span class="mw-page-title-main">Natricinae</span> Subfamily of snakes

The Natricinae are a subfamily of colubroid snakes, sometimes referred to as a family (Natricidae). The subfamily comprises 36 genera. Members include many very common snake species, such as the European grass snakes, and the North American water snakes and garter snakes. Some Old World members of the subfamily are known as keelbacks, because their dorsal scales exhibit strong keeling.

<i>Rhabdophis</i> Genus of snakes

Rhabdophis is a genus of snakes in the subfamily Natricinae of the family Colubridae. Species in the genus Rhabdophis are generally called keelback snakes, and are found primarily in Southeast Asia. The best-known species is Rhabdophis tigrinus; few other species have been studied in detail.

Common keelback may refer to several species of colubrid snakes of the subfamily Natricinae:

<i>Natrix maura</i> Species of snake

The viperine water snake or viperine snake is a semiaquatic, fish-eating natricine water snake. Despite its common names, it is not a member of the subfamily Viperinae. It was given its common names due to exhibiting a dorsal colour pattern that superficially resembles that of sympatric adder species. In comparison to other Natrix species its head is also somewhat wider and more distinct from the neck. Like most members of the Natricinae it possesses a venom gland on each side of the upper jaw that produces a mild venom that may play a role in swallowing or digestion. The gland is not associated with an enlarged specialized tooth and the venom has to be applied by chewing. The species usually does not bite as a means of defense, and the effect of a bite would be harmless to humans.

<i>Boiga nigriceps</i> Species of snake

Boiga nigriceps is a species of colubrid snake from South-East Asia. They are large snakes; adults may attain a total length of 1.75 m.

<i>Rhabdophis tigrinus</i> Species of snake

Rhabdophis tigrinus, also known commonly as the tiger keelback, yamakagashi, or kkotbaem, is a species of venomous snake in the subfamily Natricinae of the family Colubridae. The species is native to East Asia and Southeast Asia. Many sources, though not ITIS, recognize one subspecies, Rhabdophis tigrinus formosanus of Taiwan.

<i>Philodryas olfersii</i> Species of snake

Philodryas olfersii is a species of venomous snake in the family Colubridae. The species is endemic to South America.

Rhabdophis ceylonensis is endemic to the island of Sri Lanka. The species is commonly known as the Sri Lanka blossom krait, the Sri Lanka keelback, and මල් කරවලා or නිහලුවා (nihaluwa) in Sinhala. It is a moderately venomous snake.

<i>Rhabdophis swinhonis</i> Species of snake

Rhabdophis swinhonis is a species of snake in the subfamily Natricinae of the family Colubridae. The species is endemic to Taiwan. It is also known commonly as the Taiwan keelback and Swinhoe's grass snake.

Rhabdophis barbouri, also known commonly as Barbour's water snake, is a species of keelback snake in the subfamily Natricinae of the family Colubridae. The species is endemic to the Philippines.

<i>Rhabdophis helleri</i> Species of snake

Rhabdophis helleri, also known commonly as Heller’s red-necked keelback, is a venomous species of keelback snake in the subfamily Natricinae of the family Colubridae. The species is native to South Asia.

References

  1. Wogan, G.; Chan-Ard, T. (2012). "Rhabdophis subminiatus". IUCN Red List of Threatened Species . 2012: e.T192116A2042128. doi: 10.2305/IUCN.UK.2012-1.RLTS.T192116A2042128.en . Retrieved 20 November 2021.
  2. 1 2 "Rhabdophis subminiatus ". The Reptile Database. www.reptile-database.org.
  3. "เจ้าของบ้านผวา! งูลายสาบคอแดงเลื้อยเข้าบ้านพร้อมกัน 6 ตัว" [The homeowner was shocked! 6 red-necked keelback snakes slither into the house at the same time]. Ch7HD (in Thai). 2022-12-07. Retrieved 2022-12-08.
  4. 1 2 Ferlan I, Ferlan A, King T, Russell FE (1983). "Preliminary studies on the venom of the colubrid snake Rhabdophis subminatus (red-necked keelback)". Toxicon. 21 (4): 570–574. doi:10.1016/0041-0101(83)90137-x. PMID   6623495.
  5. Zotz RB, Mebs D, Hirche H, Paar D (1991). "Hemostatic changes due to the venom gland extract of the red-necked keelback snake (Rhabdophis subminiatus)". Toxicon. 29 (12): 1501–1508. doi:10.1016/0041-0101(91)90006-d. PMID   1801326.
  6. Wiktionary
  7. Schmidt, Karl P. (1925). "New reptiles and a new salamander from China". American Museum Novitates (157): 1-5. http://digitallibrary.amnh.org/dspace/handle/2246/9

Further reading