Deinagkistrodon acutusChinese Moccasin

Geographic Range

Deinagkistrodon acutus can be found in Southeastern China in the provinces of Anhwei, Chekiang, Fukien, Hunan, Hupeh, Kiangsi, Kwangsi, Kwangtung, Kweichow, extreme southeastern Szechwan, and possibly Yunnan. This species also occurs in northern Vietnam, and central and southern Taiwan. (Gloyd, 1990; Zhao and Adler, 1993)

Habitat

Sharp-nosed pit vipers prefer moist, shaded habitats usually in montane forests and foothills under 1200 m but have been documented at elevations of up to 1400 m. They occur among rocks, in vegetation along valley streams, and near farm houses where they have been known to hide in dark places in search for rodents. (Gloyd, 1990)

  • Range elevation
    200 to 1400 m
    656.17 to 4593.18 ft

Physical Description

Deinagkistrodon acutus adults range in length from 910 to 1210 mm, with the largest specimen on record measuring 1545 mm. Although D. acutus is a relatively large and stout-bodied snake, it is relatively smaller than many of the species the genus Agkistrodon. They possess a protuberant, upturned snout. Pit-vipers bear a pit on each side of the face, between the nostril and the eye, which contains a temperature sensitive pit organ. The pit organ allows animals to sense thermal radiation at specific wavelengths and may also be used in thermoregulation and predator avoidance. Each side of the body is patterned with a prominent series of 15 to 23 pairs of large dark triangles, with a base color of gray or brown. The venter is whitish and speckled with conspicuous gray and black spots that vary in size and shape. Adults have darker coloration than juveniles, which have yellowish tails until adulthood. Adult coloration bears a striking resemblance to that of southern copper-heads found in the United States. Its upturned snout, dark triangular body patterning and strongly tuberculate-keeled scales are relatively unique characteristics that help distinguish it from similar species. Deinagkistrodon acutus is sexually dimorphic, as males have longer tails and females have longer body lengths. (Barrett, 1970; Gloyd, 1990)

  • Sexual Dimorphism
  • female larger
  • Range length
    1545 (high) mm
    60.83 (high) in
  • Average length
    910 to 1210 mm
    in

Development

Optimal temperature for hatching in Deinagkistrodon acutus ranges from 22.6 C to 36.5 C, with an average of 27.6 C. Hatchlings measure about 21 cm in length. First molt tends to occur ten days after hatching. The number of molts per year is usually between three and four, but can be as many as five depending upon environmental conditions and food availability. (Gloyd, 1990)

Reproduction

Deinagkistrodon acutus is polygynandrous. Males chase females during courtship and use olfaction to investigate various parts of the female's body. Once a male has secured his mate and their heads are aligned, their tails being to wrap around each other and vibrate continuously. Mating in D. acutus can last from 2 to 6 hours. (Gloyd, 1990)

Little information is available concerning the mating behavior of Deinagkistrodon acutus. Mating has been observed from March through May and again from September through November. Gestation length ranges from 20 to 35 days. Most females are reproductively mature by 36 months of age, and clutch sizes range from 5 to 32 eggs, with an average of 20. Hatchlings range in mass from 6 to 14.5 grams. (Gloyd, 1990; Lin, et al., 2005; Zhao and Adler, 1993)

  • Breeding interval
    Deinagkistrodon acutus breeds twice yearly.
  • Breeding season
    Deinagkistrodon acutus breeds from March through May and again from September through December.
  • Range number of offspring
    5 to 32
  • Average number of offspring
    20
  • Range gestation period
    20 to 35 days
  • Average age at sexual or reproductive maturity (female)
    36 months

Deinagkistrodon acutus is oviparous and lays about 20 eggs at a time. During incubation, mothers coil themselves around their eggs for approximately 20 days, after which hatchlings emerge and are completely independent of parental care. (Gloyd, 1990)

Lifespan/Longevity

There is little information available regarding the average lifespan of Deinagkistrodon acutus. In the wild, maximum lifespan has been estimated at 20 years, and the oldest known captive individual lived for 16 years and 3 months. (Gloyd, 1990)

  • Range lifespan
    Status: captivity
    16 years and 3 months (high) years
  • Typical lifespan
    Status: wild
    20 (high) years

Behavior

There is little information available regarding the general behavior of Deinagkistrodon acutus. It is a sedentary snake, but it is easily annoyed and may attack without warning when alarmed or provoked. During winter, it occupies abandoned small-mammal borrows, from 300 m and above, that are dry, sheltered from wind, exposed to the sun, and with water sources nearby. It avoids high levels of light, except when basking in cool weather. Higher rates of activity are correlated with cloudy and rainy weather, except during the typhoon season when rates of activity are drastically reduced. In general, this species is most active between 10 C and 32 C, with an optimal thermal range of 17 C to 30 C. << Deinagkistrodon acutus>> is a nocturnal or crepuscular snake. It is considered an ambush predator and envenomates their prey in order to immobilize it. Captive individuals have been observed to remain coiled during the day, with their heads near the center of the coil. (Gloyd, 1990; Greene, et al., 1988)

Home Range

There is no information available regarding the home range of Deinagkistrodon acutus.

Communication and Perception

Pit organs, which are found in all pit vipers, help Deinagkistrodon acutus detect specific wavelengths of infrared heat emitted by prey and potential predators. Pit organs are also thought to help in thermoregulation. Fibers innervating pit-organ receptors are completely insensitive to tactile stimuli but visual and infrared stimuli allow the snake to locate endothermic prey such as small rodents, especially in the dark. Like many other snakes and lizards, the tongue of D. acutus is used for olfactory perception. Vomeronasal functioning is essential for the initiation of male courtship of reproductively active females during breeding season. (Barrett, 1970; Mason and Halpern, 1992; Molenaar, 1992)

Food Habits

Deinagkistrodon acutus is carnivorous. Their general diet consists of birds, rodents, lizards, frogs and toads. After large meals, snakes may remain motionless for days. (Gloyd, 1990; Greene, et al., 1988)

  • Primary Diet
  • carnivore
    • eats terrestrial vertebrates
  • Animal Foods
  • birds
  • mammals
  • amphibians
  • reptiles

Predation

Deinagkistrodon acutus has no known predators. However, it is vulnerable to attack by conspecifics and ophiophagous (i.e., cannabalistic) snakes. Anti-predator adaptations include cloacal discharge where the contents of the cloaca are expelled in a fine stream or spray, sometimes ejected a considerable distance. In addition, pit-vipers assume a "body bridge" position in which a portion of the body is raised in the direction of a predator. This species' quick-strike capabilities and venomous bite likely deter potential predators and reduce predation risk. (Gloyd, 1990; Greene, et al., 1988)

Ecosystem Roles

Deinagkistrodon acutus preys upon small animals such as birds, rodents, lizards, frogs and toads. As a result, it may help control certain agricultural pest species (e.g., small rodents) throughout its geographic range. Known parasites of this species include pentastomid endoparasites and one species of spiny-headed worm. (Gloyd, 1990)

Commensal/Parasitic Species
  • spiny-headed worm, (Centrorhynchus spilornae)
  • pentastomid endoparasites, (Armillifer agkistrodontis)

Economic Importance for Humans: Positive

D. acutus has both commercial and medicinal importance in China. Its venom has been used for centuries as a traditional remedy for rheumatiod arthritis and pain in tendons and bones. More recently, the venom's anticoagulation attributes have been incorporated in hemostatic and thrombolytic drugs, which are widely used to prevent harmful blood clotting in stroke victims. (Gloyd, 1990)

Economic Importance for Humans: Negative

Deinagkistrodon acutus is known for entering homes in search of food and its bite is lethal to humans. (Zhao and Adler, 1993)

  • Negative Impacts
  • injures humans
  • household pest

Conservation Status

Although Deinagkistrodon acutus is not listed on the IUCN's Red List of Threatened Species, China has listed this species as "vulnerable". Many populations throughout China have declined due to over-exploitation and habitat destruction. As a result, China began a captive breeding program that, so far, has been successful in decreasing commercial exploitation of wild populations. (Huang, et al., 2007)

Other Comments

Common names for Deinagkistrodon acutus include Chinese moccasin, hundred-pacer, sharp-nosed viper, and snorkel viper. The venom of D. acutus contains a potent neurotoxin that is potentially lethal to humans. Its large, hinged fangs allow for effective delivery of large quantities of venom. Immediate bite symptoms include severe localized pain and bleeding. Several proteases in the venom are responsible for local tissue damage and immediate hemorrhagic symptoms. These symptoms are followed by swelling, blistering, necrosis, and ulceration. Systemic symptoms, which often include heart palpitations, may occur suddenly and soon after being bit. Deinagkistrodon acutus is responsible for many of the snake-bite related moralities in southern China and Taiwan. Fortunately, researchers have been able to manufacture a monovalent antivenin to administer to bite-victims. However, the antivenin is only effective if taken within a few hours of the bite. (Chen, et al., 2002; Zhao and Adler, 1993)

Contributors

Jennifer Vicente (author), The College of New Jersey, Matthew Wund (editor), The College of New Jersey, John Berini (editor), Animal Diversity Web Staff.

Glossary

acoustic

uses sound to communicate

agricultural

living in landscapes dominated by human agriculture.

carnivore

an animal that mainly eats meat

chemical

uses smells or other chemicals to communicate

crepuscular

active at dawn and dusk

drug

a substance used for the diagnosis, cure, mitigation, treatment, or prevention of disease

female parental care

parental care is carried out by females

fertilization

union of egg and spermatozoan

forest

forest biomes are dominated by trees, otherwise forest biomes can vary widely in amount of precipitation and seasonality.

fossorial

Referring to a burrowing life-style or behavior, specialized for digging or burrowing.

heterothermic

having a body temperature that fluctuates with that of the immediate environment; having no mechanism or a poorly developed mechanism for regulating internal body temperature.

infrared/heat

(as keyword in perception channel section) This animal has a special ability to detect heat from other organisms in its environment.

iteroparous

offspring are produced in more than one group (litters, clutches, etc.) and across multiple seasons (or other periods hospitable to reproduction). Iteroparous animals must, by definition, survive over multiple seasons (or periodic condition changes).

mountains

This terrestrial biome includes summits of high mountains, either without vegetation or covered by low, tundra-like vegetation.

native range

the area in which the animal is naturally found, the region in which it is endemic.

nocturnal

active during the night

oriental

found in the oriental region of the world. In other words, India and southeast Asia.

World Map

oviparous

reproduction in which eggs are released by the female; development of offspring occurs outside the mother's body.

pheromones

chemicals released into air or water that are detected by and responded to by other animals of the same species

polygynandrous

the kind of polygamy in which a female pairs with several males, each of which also pairs with several different females.

seasonal breeding

breeding is confined to a particular season

sedentary

remains in the same area

sexual

reproduction that includes combining the genetic contribution of two individuals, a male and a female

temperate

that region of the Earth between 23.5 degrees North and 60 degrees North (between the Tropic of Cancer and the Arctic Circle) and between 23.5 degrees South and 60 degrees South (between the Tropic of Capricorn and the Antarctic Circle).

terrestrial

Living on the ground.

territorial

defends an area within the home range, occupied by a single animals or group of animals of the same species and held through overt defense, display, or advertisement

venomous

an animal which has an organ capable of injecting a poisonous substance into a wound (for example, scorpions, jellyfish, and rattlesnakes).

vibrations

movements of a hard surface that are produced by animals as signals to others

visual

uses sight to communicate

References

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