Rhabdophis

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Rhabdophis
Rhabdop submin 080217-4693 ipb.jpg
Rhabdophis subminiatus
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Reptilia
Order: Squamata
Suborder: Serpentes
Family: Colubridae
Subfamily: Natricinae
Genus: Rhabdophis
Fitzinger, 1843
Species

30, see text.

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.

Contents

Toxicity

Rhabdophis is often thought of as completely harmless, but there are several cases of severe envenomation and at least one recorded fatality from the Japanese species. [1] The symptoms have been compared to those of highly venomous African colubrids such as the boomslang. [1] Similar reports exist for other species of the genus, [2] which also make reference to the highly hemorrhagic nature of the venom. There is a supposed antivenom in Japan, but not in other countries. [2]

While the term "poisonous snake" is often incorrectly used for a wide variety of venomous snakes, some species of Rhabdophis are in fact poisonous but not venomous. Keelback snakes have salivary glands that secrete poison they ingest from eating poisonous toads. While both venom and poison are toxins, a venom requires direct delivery, for instance subcutaneously through a snake bite, but can be ingested without harm. A poison can also be absorbed indirectly, e.g., by touch or through the digestive system, [3] or delivered by the fang of a poisonous snake. [4] [5] Rhabdophis ingest poisonous toads and the poison is absorbed into their blood stream, but the snake is immune to it. The toad poison accumulates in the snakes' salivary glands and is secreted when they bite. Therefore, they use toad poison as their venom. Although this is harmful to small rodents, they cannot harm humans as the concentration of poison secreted is very low.

Species

These species are recognized as being valid: [6]

Nota bene : A binomial authority in parentheses indicates that the species was originally described in a genus other than Rhabdophis.

Related Research Articles

<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">Hognose</span> Common name for several snake species

Hognose snake is a common name for several unrelated species of snakes with upturned snouts, classified in two colubrid snake families and one pseudoxyrhophiid snake family.

<span class="mw-page-title-main">Venomous mammal</span> Venom-producing animals of the class Mammalia

Venomous mammals are animals of the class Mammalia that produce venom, which they use to kill or disable prey, to defend themselves from predators or conspecifics or in agonistic encounters. Mammalian venoms form a heterogeneous group with different compositions and modes of action, from four orders of mammals: Eulipotyphla, Monotremata, Primates, and Chiroptera. To explain the rarity of venom delivery in Mammalia, Mark Dufton of the University of Strathclyde has suggested that modern mammalian predators do not need venom because they are able to kill quickly with their teeth or claws, whereas venom, no matter how sophisticated, requires time to disable prey.

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

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 snakes, it is also poisonous.

<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.

<i>Ahaetulla</i> Genus of snakes

Ahaetulla, commonly referred to as Asian vine snakes or Asian whip snakes, is a genus of colubrid snakes distributed throughout tropical Asia. They are considered by some scientists to be mildly venomous and are what is commonly termed as 'rear-fanged' or more appropriately, opisthoglyphous, meaning their enlarged teeth or fangs, intended to aid in venom delivery, are located in the back of the upper jaw, instead of in the front as they are in vipers or cobras. As colubrids, Ahaetulla do not possess a true venom gland or a sophisticated venom delivery system. The Duvernoy's gland of this genus, homologous to the venom gland of true venomous snakes, produces a secretion which, though not well studied, is considered not to be medically significant to humans.

<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.

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

<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>Tachymenis</i> Genus of snakes

Tachymenis is a genus of venomous snakes belonging to the family Colubridae. Species in the genus Tachymenis are commonly known as slender snakes or short-tailed snakes and are primarily found in southern South America. Tachymenis are rear-fanged (opisthoglyphous) and are capable of producing a medically significant bite, with at least one species, T. peruviana, responsible for human fatalities.

<span class="mw-page-title-main">Poisonous amphibian</span> Amphibians that produce poison

Poisonous amphibians are amphibians that produce toxins to defend themselves from predators.

<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.

<span class="mw-page-title-main">Poisonous fish</span> Fish containing indigestible toxins

Poisonous fish are fish that are poisonous to eat. They contain toxins which are not destroyed by the digestive systems of animals that eat the fish. Venomous fish also contain toxins, but do not necessarily cause poisoning if they are eaten, since the digestive system often destroys their venom.

<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.

<span class="mw-page-title-main">Toxungen</span>

Toxungen comprises a secretion or other body fluid of one or more biological toxins that is transferred by one animal to the external surface of another animal via a physical delivery mechanism. Toxungens can be delivered through spitting, spraying, or smearing. As one of three categories of biological toxins, toxungens can be distinguished from poisons, which are passively transferred via ingestion, inhalation, or absorption across the skin, and venoms, which are delivered through a wound generated by a bite, sting, or other such action. Toxungen use offers the evolutionary advantage of delivering toxins into the target's tissues without the need for physical contact.

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.

References

  1. 1 2 Mittleman, M. B.; Goris, R. C. (27 February 1978). "Death Caused by the Bite of the Japanese Colubrid Snake Rhabdophis tigrinus (Boie) (Reptilia, Serpentes, Colubridae)". Journal of Herpetology. 12 (1). JSTOR: 109–111. doi:10.2307/1563518. ISSN   0022-1511. JSTOR   1563518.
  2. 1 2 Nelwan, Erni Juwita, et al. (2016)."Severe coagulopathy and transient hypertension following a Rhabdophis subminiatus bite: a case report". Revista da Sociedade Brasileira de Medicina Tropical [online]. 49 (4): 520–522. [Accessed 16 November 2021]. Available from: <https://doi.org/10.1590/0037-8682-0314-2015>. ISSN 1678-9849. https://doi.org/10.1590/0037-8682-0314-2015.
  3. Oldfield, Molly; Mitchinson, John (10 September 2010). "QI: Quite Interesting facts about deadly poisons". The Telegraph.
  4. Zotz, R. B.; Mebs, D.; Hirche, H.; Paar, D. (1 January 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.
  5. Ferlan, I.; Ferlan, A.; King, T.; Russell, F. E. (1 January 1983). "Preliminary studies on the venom of the colubrid snake Rhabdophis subminatus [sic] (red-necked keelback)". Toxicon. 21 (4): 570–574. doi:10.1016/0041-0101(83)90137-X. PMID   6623495.
  6. Genus Rhabdophis at The Reptile Database. www.reptile-database.org.
  7. 1 2 Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN   978-1-4214-0135-5. (Rhabdophis barbouri, p. 16; R. swinhonis, p. 258).

[1]

Further reading


  1. "Definition of POISON".