Elaphe
   HOME

TheInfoList



OR:

''Elaphe'' is a
genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...
of snakes in the
family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Colubridae Colubridae (, commonly known as colubrids , from , 'snake') 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. C ...
. ''Elaphe'' is one of the main
genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...
of the
rat snake Rat snakes are members – along with kingsnakes, milk snakes, Oxybelis, vine snakes and indigo snakes – of the subfamily Colubrinae of the family Colubridae. They are medium to large Constriction, constrictors and are found throughout much o ...
s, which are found in many regions of the northern hemisphere. ''Elaphe''
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
are medium to large constrictors by nature. Based on the
mitochondrial DNA Mitochondrial DNA (mtDNA and mDNA) is the DNA located in the mitochondrion, mitochondria organelles in a eukaryotic cell that converts chemical energy from food into adenosine triphosphate (ATP). Mitochondrial DNA is a small portion of the D ...
analysis results, many species of ''Elaphe'' have been moved to the genera '' Bogertophis'', '' Coelognathus'', '' Gonyosoma'', ''Orthriophis'', ''
Pantherophis ''Pantherophis'' is a genus of nonvenomous colubrid snakes endemic to central and eastern regions of North America. It consists of the North American ratsnakes, the fox snake, foxsnakes, and the cornsnakes. The genus, which contains 10 recognize ...
'', '' Rhinechis'', '' Senticolis'', '' Zamenis'', and others. Nevertheless, the generic name ''Elaphe'' is still widely used.


Physical characteristics

Like most of the
rat snake Rat snakes are members – along with kingsnakes, milk snakes, Oxybelis, vine snakes and indigo snakes – of the subfamily Colubrinae of the family Colubridae. They are medium to large Constriction, constrictors and are found throughout much o ...
s, ''Elaphe'' spp. generally have slender but sturdy bodies, square heads, and extremely flat bellies. Their sizes range from large medium to very large, Wright, A.H.; Wright, A.A. (1957). ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock Publishing Associates, a Division of Cornell University Press. 1,105 pp. (in 2 volumes). ("Rat Snakes", p. 209; ''Elaphe emoryi'', longevity, p. 220). growing even as large as 2.75m (108 in). ''Elaphe'' spp. have large numbers of
vertebrae Each vertebra (: vertebrae) is an irregular bone with a complex structure composed of bone and some hyaline cartilage, that make up the vertebral column or spine, of vertebrates. The proportions of the vertebrae differ according to their spinal ...
, ribs, and ventral scales, but few rows of dorsal scales, which are characterized by having slight keels. In cross section, ''Elaphe'' spp. are shaped like a loaf of bread, the flat belly meeting the sides of the body at an angle. This special physical characteristic is well observed in ''Elaphe obsoleta'' (now considered '' Pantherophis obsoletus''), whose belly scales curve upward. The curving of the ventral scales gives them better traction for tree climbing. Wernert, S.J. (1982). ''Reptiles. Reader's Digest North American Wild Life''. Pleasantville, New York: Reader's Digest. p. 174. The color and pattern of ''Elaphe'' spp. are quite variable and hard to generalize. Internally, ''Elaphe'' spp. do not have any observable
vestige Vestigiality is the retention, during the process of evolution, of genetically determined structures or attributes that have lost some or all of the ancestral function in a given species. Assessment of the vestigiality must generally rely on co ...
s of hind limbs or coronoid bones of the lower jaw like any other members of the family
Colubridae Colubridae (, commonly known as colubrids , from , 'snake') 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. C ...
. Another important characteristic of ''Elaphe'' as part of the Colubridae is the presence of
Duvernoy's gland The Duvernoy's gland is a gland found in some groups of ''colubridae, colubrid'' snakes. It is distinguished from the venom gland and is not found in ''viperidae, viperids'' or ''elapidae, elapids''. It was named for France, French zoologist Geo ...
, a modified salivary and digestive gland. In addition, ''Elaphe'' spp. have equal and smooth
maxillary teeth A tooth (: teeth) is a hard, calcified structure found in the jaws (or mouths) of many vertebrates and used to break down food. Some animals, particularly carnivores and omnivores, also use teeth to help with capturing or wounding prey, tearin ...
. The teeth are small and slightly curved, and occur in several rows. The curved teeth help fix the prey and prevent them from escaping once they are caught.


Senses

''Elaphe'' spp. have very developed sensory organs which support their daily activities. They have internal ears that enables them to detect sounds at low frequencies. The ears consist of a single ear bone connected to a jaw bone. Compared to other snakes, they are considered to have highly developed vision that allows them to detect the movement of their
predator Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...
s and
prey Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not ki ...
. The eyes are protected by single transparent
brille The brille (also called the ocular scale, eye cap or spectacle) is the layer of transparent, immovable disc-shaped skin or scale covering the eyes of some animals for protection, especially in animals without eyelids. In squamate reptiles both ...
s. In addition, the analysis of scents is carried out by
Jacobson's organ The vomeronasal organ (VNO), or Jacobson's organ, is the paired auxiliary olfactory (smell) sense organ located in the soft tissue of the nasal septum, in the nasal cavity just above the roof of the mouth (the hard palate) in various tetrapods. T ...
in the palate. To stimulate Jacobson's organ, they use their tongues to transport air and ground molecules to Jacobson's organ. Then, the organ analyzes the molecules to identify the scent. Among these detectable scents are
pheromones A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavi ...
, which indicate the presence of other snakes and their reproductive readiness.


Lifecycle and behavior

The lifespan of ''Elaphe'' spp. is generally 15 years. Males live a little longer than females,"Rat snakes – lifecycle, predation, diet, bites, hibernation, pictures and videos."
Ratsnake.org. (2010-09-23).
but some species, such as ''E. guttata'' (now considered '' Pantherophis guttatus''), live up to 23 years in captivity. However, species such as ''E emoryi'' (now considered '' Pantherophis emoryi'') usually have lifespans around 2 years and 2 months. ''Elaphe'' spp. generally reach sexual maturity after 18–24 months. They usually mate with the opposite sex after emerging from
hibernation Hibernation is a state of minimal activity and metabolic reduction entered by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It is mos ...
in the spring. The
gestation Gestation is the period of development during the carrying of an embryo, and later fetus, inside viviparous animals (the embryo develops within the parent). It is typical for mammals, but also occurs for some non-mammals. Mammals during pregn ...
period of females is around 1.5 months, and females can lay up to 30 eggs in a clutch, the number varying between species. ''E. guttata'' and ''E. obsoleta'', among others, are mostly diurnal, but some species are more active in late afternoon or at dusk. Throughout the year, they are usually active from April to October, followed by a period of hibernation.


Hibernation

''Elaphe'' spp.
hibernate Hibernation is a state of minimal activity and metabolic reduction entered by some animal species. Hibernation is a seasonal heterothermy characterized by low body-temperature, slow breathing and heart-rate, and low metabolic rate. It is most ...
, especially those that live in cold regions, because snakes are cold-blooded, which makes their body temperature susceptible to the temperature of their environments. Thus, they need to maintain their body energy by switching locations and remaining physiologically inactive when winter comes. The hibernacula sites vary depending on the habitats they live in, yet the most important requirement of a hibernaculum site is that it needs to be frost-free. Some ''Elaphe'' spp. hibernate in the rock crevices, rock faults, and burrows. Roots, C. (2006)
Uncontrolled Hypothermia. Hibernation
Westport, Conn.: Greenwood Press, p. 88, .
However, other species choose to hibernate in rotting logs, roots of trees, and hollow spaces in elevated tree trunks. Some snakes that live close to human communities even hibernate in old wells and barns. Most members of the genus ''Elaphe'' start their hibernation in October and emerge again the next spring. The length of the hibernation varies by species. '' Elaphe longissima'', or Aesculapian snake, may hibernate from October to May, as it is among the northernmost occurring rat snakes. However, '' Elaphe bimaculata'', or the twin-spotted rat snake, only needs to hibernate for 2 to 3 months.Knight, Rex; Korell, Sacha (1997)
"Ratsnakes of the Genus Elaphe – Species."
Ratsnakes of the Genus ''Elaphe'' – Introduction. OnlineHobbyist.com, Inc. (2010-09-22).
Species such as black rat snakes, or ''E. obsoleta'', hibernate with other rat snakes and/or many other snake species, most notably timber
rattlesnake Rattlesnakes are venomous snakes that form the genus, genera ''Crotalus'' and ''Sistrurus'' of the subfamily Crotalinae (the pit vipers). All rattlesnakes are vipers. Rattlesnakes are predators that live in a wide array of habitats, hunting sm ...
s, racers, and bull snakes.LeClere, Jeff (2005)
Iowa Reptiles and Amphibians – Rat Snake – ''Elaphe obsoleta''.
HerpNet – Home. Web. 22 Sept. 2010.


Reproduction

''E. obsoleta'' generally starts to mate in late April, May, and early June after the winter hibernation. Males try to attract females with
pheromones A pheromone () is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting like hormones outside the body of the secreting individual, to affect the behavi ...
, as the females pass through their territories. Male Aesculapian snakes pursue female snakes until they can coil around them. They continue in such position, which is then followed by dancing for up to an hour before
copulation Sexual intercourse (also coitus or copulation) is a sexual activity typically involving the insertion of the erect male penis inside the female vagina and followed by thrusting motions for sexual pleasure, reproduction, or both.Sexual inte ...
, during which the male snake lines up with the female and holds her in place by wrapping his tail around hers and grasping her with his mouth. Then, the male everts one of his hemipenes into the female's
cloaca A cloaca ( ), : cloacae ( or ), or vent, is the rear orifice that serves as the only opening for the digestive (rectum), reproductive, and urinary tracts (if present) of many vertebrate animals. All amphibians, reptiles, birds, cartilagin ...
. The mating process lasts from a few minutes to a few hours.Trepanowski, P. (2003)
"''Elaphe obsoleta''"
Animal Diversity Web The Animal Diversity Web (ADW) is a non-profit group that hosts an online database site that collects natural history, classification, species characteristics, conservation biology, and distribution information on species of animals. The website ...
. Accessed September 22, 2010.
After copulation, ''Elaphe'' spp. seek an appropriate place to lay the developing eggs. They usually lay eggs in the soft heart of a rotten log or in sandy soil under a rock. A good place for laying eggs is one that is damp but not wet, and warm but not hot. After laying eggs, the female snake covers them up with sand or soil, and then she leaves.Bateman, G. (1981). Snakes. The Encyclopedia of Reptiles and Amphibians (pp. 115, 117). A few species remain with the eggs until they hatch about 9 weeks later. Oviparous ''E. obsoleta'' lays 12–20 eggs under logs or leaves in late summer, which hatch in the fall. The adult snakes return to their hibernation dens in the late fall. ''E. guttata'' breeds from March to May. The mating process is similar to ''E. obsoleta''. ''E. guttata'' lays 10–30 eggs in late May to July. The eggs are generally not protected by the adults. After 60–65 days, the eggs hatch in July through September.


Defense mechanisms

Many species of ''Elaphe'' are known for being nonaggressive and shy. They are prone to freeze their movements when they are shocked or encountering danger. This motionless response has contributed to many road kills of ''Elaphe''. However, some ''Elaphe'' spp. tend to be more defensive if they are continually provoked. For example, Texas rat snakes, '' Elaphe obsoleta lindheimeri'', are well known as one of the most snappy and combative rat snakes. In general, their defense system can be broken down to two levels. The first line of defense involves specific behaviors that they use to warn the intruders. One of the most common ways is by coiling their bodies and vibrating their tails, which simulates a rattle. Fox snakes, ''Elaphe vulpina'' (now considered '' Pantherophis vulpinus'') and ''Elaphe gloydi'' (now considered '' Pantherophis gloydi''), exemplify this type of defense mechanism; they mimic the rattling vibration of rattlesnakes when they encounter danger. Burton, M.; Burton, R. (1969). "Rat Snake". ''The International Wildlife Encyclopedia.'' (pp. 1909–1910). New York: Marshall Cavendish Corp. Another common way of defense is by smearing a foul-smelling
musk Musk is a class of aromatic substances commonly used as base notes in perfumery. They include glandular secretions from animals such as the musk deer, numerous plants emitting similar fragrances, and artificial substances with similar odors. ' ...
on their predators. The musk is originated from the contents of the
anal gland The anal glands or anal sacs are small glands near the anus in many mammals. They are situated in between the external anal sphincter muscle and internal anal sphincter muscle. In non-human mammals, the secretions of the anal glands contain most ...
and the intestinal tract. The second line of defense, generally involves striking the intruder with their teeth if they are further provoked.


Locomotion

''Elaphe'' spp. move forward using side-to-side, serpentine movement. They use the curved ventral scales of their bodies to grab the rough ground surfaces and then push against the ground to generate a forward movement. Thus, the smoother the ground is, the harder it is for them to move across it. Many species apply similar mechanisms when climbing trees.


Predation

Adult ''Elaphe'' spp. primarily prey on
rodent Rodents (from Latin , 'to gnaw') are mammals of the Order (biology), order Rodentia ( ), which are characterized by a single pair of continuously growing incisors in each of the upper and Mandible, lower jaws. About 40% of all mammal specie ...
s (''i.e''., mice and chipmunks), bird eggs, and young birds. Juveniles feed on small lizards, young mice, and occasionally small frogs (''i.e''., tree frogs). ''Elaphe'' spp. hunt by waiting motionless in a fixed position until the prey comes near enough to attack. Then, they strike the prey and bite it. They use their
Jacobson's organ The vomeronasal organ (VNO), or Jacobson's organ, is the paired auxiliary olfactory (smell) sense organ located in the soft tissue of the nasal septum, in the nasal cavity just above the roof of the mouth (the hard palate) in various tetrapods. T ...
to track and find their prey. George, L. (2002)
Mating. Rat Snake
(1 ed.), Mankato, Minnesota: Capstone Press, pp. 33–34, .
Being constrictors, ''Elaphe'' spp. kill the prey by creating enormous pressure on the prey's chest. As they continue to coil more tightly, the pressure on the chest prevents the blood from circulating into the heart, which eventually leads to heart failure. They usually bite the prey first to maintain their grip on the prey before they start this deadly mechanism. In addition, they do not chew their food, but swallow it whole.


Habitat and distribution

''Elaphe'' spp. live in a great variety of environments, depending on species and subspecies. Most are terrestrial or semiarboreal, but some burrow in sand or loose soil. The genus formerly contained species found on every continent except Antarctica. Taxonomic revisions have renamed most of these former ''Elaphe'', leaving only 10 Eurasian taxa remaining in ''Elaphe''.


Species

The following 18 species are recognized as being valid. www.reptile-database.org. * '' Elaphe anomala'' ( Boulenger, 1916) * '' Elaphe bimaculata''
Schmidt Schmidt may refer to: * Schmidt (surname), including list of people and fictional characters with the surname * Schmidt (singer) (born 1990), German pop and jazz singer * Schmidt (lunar crater), a small lunar impact crater * Schmidt (Martian c ...
, 1925
– Chinese leopard snake * '' Elaphe cantoris'' (Boulenger, 1894) – eastern trinket snake * '' Elaphe carinata'' ( Günther, 1864) – Taiwan stink snake * '' Elaphe climacophora'' ( H. Boie, 1826) – Japanese rat snake * '' Elaphe davidi'' ( Sauvage, 1884) – Pere David's rat snake * '' Elaphe dione'' (
Pallas Pallas may refer to: Astronomy * 2 Pallas asteroid ** Pallas family, a group of asteroids that includes 2 Pallas * Pallas (crater), a crater on Earth's moon Mythology * Pallas (Giant), a son of Uranus and Gaia, killed and flayed by Athena * Pa ...
, 1773)
– steppe rat snake * '' Elaphe druzei'' Jablonski, Ribeiro Jr., Simonov, Šoltys, & Meiri, 2023 * '' Elaphe hodgsoni'' (Günther, 1860) * '' Elaphe moellendorffi'' ( Boettger, 1886) – flower snake, Moellendorf’s rat snake * '' Elaphe quadrivirgata'' (H. Boie, 1826) – Japanese four-lined rat snake * '' Elaphe quatuorlineata'' ( Lacépède, 1789) – four-lined snake * '' Elaphe sauromates'' (Pallas, 1811) – blotched rat snake, Sarmatian rat snake, eastern four-lined rat snake * '' Elaphe schrenckii''
Strauch Strauch, a German word meaning ''bush'' or ''shrub A shrub or bush is a small to medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. ...
, 1873
– Amur rat snake, Siberian rat snake * '' Elaphe taeniura'' (
Cope A cope ( ("rain coat") or ("cape")) is a liturgical long mantle or cloak, open at the front and fastened at the breast with a band or clasp. It may be of any liturgical colour. A cope may be worn by any rank of the Catholic or Anglican clerg ...
, 1861)
– beauty snake, Taiwan beauty snake; Sakishima beauty snake; blue beauty rat snake * '' Elaphe urartica'' Jablonski, Kukushkin, Avcı, Bunyatova, Ilgaz, Tuniyev & Jandzik, 2019 – Urartian rat snake * '' Elaphe xiphodonta'' Qi, Shi, Ma,
Gao Gao (or Gawgaw/Kawkaw) is a city in Mali and the capital of the Gao Region. The city is located on the River Niger, east-southeast of Timbuktu on the left bank at the junction with the Tilemsi valley. For much of its history Gao was an imp ...
, Bu, Grismer, Li &
Wang Wang may refer to: Names * Wang (surname) Wang () is the pinyin romanization of Chinese, romanization of the common Chinese surname (''Wáng''). It has a mixture of various origin with uncertain lineage of family history, however it is c ...
, 2021
– Qin Emperor rat snake, blade-toothed rat snake * '' Elaphe zoigeensis'' Huang, Ding, Burbrink,
Yang Yang may refer to: * Yang, in yin and yang, one half of the two symbolic polarities in Chinese philosophy * Korean yang, former unit of currency of Korea from 1892 to 1902 * YANG, a data modeling language for the NETCONF network configuration p ...
, Huang, Ling, Chen & Zhang, 2012
– Zoige rat snake


References


External links

* {{Authority control Rat snakes Snake genera Taxa named by Johann Georg Wagler