Green tree python

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Green tree python
Green tree python (Morelia viridis)

Green tree python ( Morelia viridis )

without rank: Toxicofera
Subordination : Snakes (serpentes)
Superfamily : Python-like (Pythonoidea)
Family : Pythons (Pythonidae)
Genre : Diamond pythons ( Morelia )
Type : Green tree python
Scientific name
Morelia viridis
( Schlegel , 1872)

The Grünebaum Python ( Morelia viridis ) is an arboreal snake from the genus of diamond pythons ( Morelia ) within the family of pythons (Pythonidae). The species occurs on New Guinea , the offshore islands and on the Cape York Peninsula in northern Australia .


The green tree python is characterized by a relatively slim body, the relatively long tail accounts for about 14% of the total length. The head is large and clearly set off from the neck. He is on the top posterior strongly arched, the muzzle is large and angular. The body is triangular in cross section with a clearly visible spine . The species reaches a total length of 150 to 180 centimeters, large females reach a length of up to 200 centimeters. The size varies depending on the area of ​​origin. The weight depends heavily on the nutritional status of the animal. Males can weigh around 1100 to 1400 grams, females up to 1600 grams, and particularly large specimens up to 2200 grams. As with most snakes, the females are slightly larger and heavier than the males.


The rostral is large, clearly set off and often notched so deep that the snout at the front often appears to be split. The nasals are arched and have large nostrils that point backwards and upwards. The two internasalia are round and separated from one another by several smaller scales. Otherwise, the top of the head does not show any larger scales; there may be 20 small scales between the eyes.

In the side view there are 60 or more small, irregularly shaped Lorealia between the nasal and the eye . There are no clearly developed preocularia or postocularia ; There are 11–19 small scales around the eye and two supralabials border the eye from below. The number of supralabials can be between 12 and 16, the first two showing deep, sloping labial pits , the third showing a shallow depression. The posterior 6–7 of a total of 14–18 infralabials show deep labial pits.

The number of abdominal scales ( ventral shields ) varies between 219 and 254, the number of subcaudalia between 68 and 129 and the number of dorsal rows of scales in the middle of the body between 55 and 57. In addition to the anal shield, there may be two dorsal spurs that are variable in shape .


Green tree python during the change in color

The basic color of adult animals is a rich green tone on top, which can appear in many shades, very rarely pure blue specimens also appear. For this reason, a scale of wide, white spots are distributed, which are often particularly concentrated on the keel-like back and sometimes form an almost continuous band there. Occasionally these spots are united to form larger, more extensive spots. The color of the abdomen and lips varies from beige-white to yellow. The tip of the tail is brownish or black. The pupils are slit vertically. The iris is silver in color.

The change in color of the young ( ontogenetic color change), as also occurs in some other snake species, is unusual . When young animals are colored bright yellow or red to red-brown, the animals do not take on their final color until they are six to ten months old. The tip of the tail is light yellow and is used to attract prey. This behavior decreases with increasing age, but could also be observed in adult animals. The complete color change can also be completed within a few weeks or, in the case of some animals, take 2 to 3 years. Why the young animals have such a bright color is not entirely clear. It is assumed that in this way an optimal camouflage in the play of light and shadow of the rainforest is possible or that various natural enemies consider the young animal to be a poisonous plant.

distribution and habitat

The distribution area of the green tree python extends to the tropical rainforests of Papua New Guinea, its offshore islands and the Cape York Peninsula in Australia. Occurrences up to 2,000 meters above sea level have been proven. The island of Gag is recorded as the westernmost point of discovery, the island of Normanby , an island off New Guinea, was reported as the easternmost point . The distance between these two points is around 3,000 kilometers as the crow flies.

In the rainforest areas there is no change in the climate in relation to the season. The amount of precipitation is significantly higher than the evaporation rate and varies in the range of the green tree python between 2,100 and 3,400 mm per year depending on the location. Correspondingly, the relative humidity is also very high and is 70 to 85 percent during the day and increases to values ​​of 95 to 100 percent at night. The temperature fluctuates between 27 and 32 degrees Celsius during the day and drops to 22 to 25 degrees at night.


Green tree python at rest

The green tree python spends most of its life in trees or shrubs. In northeast Australia, juveniles stay at heights up to a maximum of 10 m, while adult specimens mostly use trees over the entire height and are often found at heights above 25 m. In the rest phases the animals assume a characteristic position. The body hangs in several tight loops over a branch, with the head resting in the middle.

Hunting style and diet

The species is a stalker. The main hunting strategy is to wait motionless in a suitable place until prey comes within range. The green tree python is very true to its location; the animals stay in a suitable place for up to 14 days. When hunting in ambush, the python forms an approximate "8" with the front third of the body in one plane, so that it can very quickly bridge a certain distance with its head and bite into it. For young animals this distance is about 10 cm, for larger animals about 40 cm.

Green tree python devouring a prey

Detailed studies of hunting activity and diet have so far only been carried out in northeastern Australia. The daily hunting activity was dependent on both sex and body size. Young animals hunted mostly during the day. With increasing size, the hunting activity of both sexes was shifted more and more to the night. Males with a head-torso length over 100 cm hunted almost exclusively at night, females of this size hunted 10–20% during the day. The small-scale hunting habitat varied depending on age and time of day. Young animals were never found lying in wait on the ground, immature and adult specimens during the day in less than 1% of the cases. At night, 15% of all detections of immature snakes were made in lurking position on the ground, in adult animals this proportion rose to 29%.

The food mainly consists of small mammals and lizards, birds and insects are also eaten. So far, data on nutrition that go beyond random observations are only available from northeast Australia, where the prey spectrum was determined on the basis of eight faecal samples and four direct observations. The main prey of immature and adult animals was Melomys capensis , belonging to the mosaic- tailed rats , which was detected in five of the eight fecal samples; other prey were an undetermined skink , two undefined birds and two butterflies. The skink Carlia longipes , an undetermined skink and a beetle were once detected as prey for young snakes .


Green tree python ( Morelia viridis ), young animal

Like all pythons, the green tree python is oviparous . He's a non-seasonal snake. This means that mating, egg laying and hatching of the young can take place at any time of the year. Most pairings take place from September to late October. When the snakes reach sexual maturity at the age of two and a half to three years, they start looking for a sexual partner. If the female meets several males to mate, multiple mating with changing sex partners is also possible. Females stop feeding some time after successfully mating and start looking for a suitable place to lay their eggs. Higher-lying caves in trees are preferred, but every hidden place that offers sufficient protection from enemies and sufficient moisture is assumed as a breeding place. The female lays her 5 to 35 eggs in hiding between February and March, after 70 to 90 days of gestation. The size of the clutch depends on the size and age of the female. Like most pythons, the green tree python is also responsible for brood care . The female puts her body loops around the clutch for 45 to 65 days and uses strong muscle contractions to keep the temperature at 29.5 degrees Celsius. If the temperature rises above it, it loosens the loops and lets air into the eggs. The females fast for a period of four to five months from mating to hatching. The males, on the other hand, eat again after mating. Animals living in the wild probably only have offspring every two years. Some females may change color to blue or turquoise at the onset of pregnancy. After hatching, the young animals change their color back to their original state. A slightly blue color is rarely retained.

Specimens kept in captivity live to be around 15 to 20 years old. The average lifespan of wild animals is unknown.


Because of their tree-living way of life, Morelia viridis should be offered a high terrarium. To calculate the minimum size, the size of the terrarium 0.75 × 0.5 × 1.0 (length × depth × height in meters) should be multiplied by the length of the animal, whereby the maximum height is limited to 2 meters. The correctness of this minimum is often discussed in specialist circles, because tree pythons have already been successfully kept and reared in much smaller terrariums. In addition, terrariums that are too large or high often have disadvantages. So z. B. makes the heating of the terrarium more difficult, which can lead to the absence of an optimal temperature gradient. Some authors therefore give a minimum size of 0.90 × 0.60 × 0.60 and an ideal size of 1.20 × 0.60 × 0.6-0.75 for adult animals. Due to the distribution in tropical Australasia , an appropriate climate must be created for the animals. In order to achieve a humidity that prevails in the rainforest, it should be sprayed twice a day. Heat spots can be used for the necessary temperature of an average of 30 ° C. In addition, there should be plenty of opportunities to rest in the form of (transverse) branches or lianas.


Head study of Morelia viridis (left) and Corallus caninus

The green tree python was first described by Hermann Schlegel in 1872 under the name Python viridis . For a long time, Morelia viridis was listed as the only species of the monotypic genus Chondropython , as it has very distinctive characteristics due to its prehensile tail with divided scales on the underside of the tail and the lack of anterior maxillary teeth and differs from all other diamond pythons (genus Morelia). As far as we know today, these are merely adjustments to the tree-dwelling way of life that emerged within the genus Morelia , and thus the green tree python is not to be delimited as a separate genus, but must be included in this genus. He is in sister group relationship to the diamond python ( Morelia spilota ). Since the individual island populations sometimes differ more or less morphologically, it is discussed to establish them as subspecies. At present, the animals are differentiated according to their area of ​​origin and their typical characteristics and viewed as local forms ( Aru , Sorong , Biak , Kofiau etc.).

The Grünebaum Python ( Morelia viridis ) has a strong anatomic similarity to the South American Hundskopfschlinger ( Corallus caninus ), which in the subfamily of the constrictor snakes is provided (Boinae). The two species are therefore not closely related and thus an example of biological convergence .


Green tree python

The locals in New Guinea call the green tree python "Jamumong", while on the Indonesian side of the island some tribes use "Ular hijau". Loosely translated, both names mean green snake. In the English-speaking world it is called "Green Tree Python". The previously valid species name Chondropython viridis was derived from the Greek words chondros (cartilage) and python (snake-like dragon in Greek mythology). The addition viridis also comes from the Greek and simply means green.

Statutory Regulations

The green tree python was included in the Washington Convention on the Protection of Species Appendix 2 and Appendix B of the EU Species Protection Ordinance . Therefore, it can be kept private without permission, but according to the Federal Species Protection Ordinance, it must be reported to the responsible state authority (Lower Nature Conservation Authority). The import and export of these animals must be approved by the Federal Agency for Nature Conservation . A certificate of origin is issued by the seller or breeder, but the regulations for this are very different from state to state.



  • Greg Maxwell: Morelia viridis - The Compendium. Chimaria Verlag, Frankfurt am Main 2005. ISBN 3-930612-79-8
  • Markus Weier, Ralf Vitt: The green tree python. Herpeton Verlag, Offenbach 2 2003. ISBN 3-9806214-1-3
  • Ron Kivit, Stephen Wiseman, Andreas Kirschner: Green tree python and green dog-headed boa. Kirschner & Seufer Verlag, Karlsruhe 2005. ISBN 3-9804207-9-5
  • Zdenek Vogel: Giant snakes from all over the world. Westarp Sciences. Spectrum Akademischer Verlag, Magdeburg-Oxford 4 1996. ISBN 3-89432-463-5
  • JG Walls: The Living Pythons. TFH Publications, 1998: pp. 185-194.
  • D. Wilson: Foraging ecology and diet of an ambush predator: the Green Python (Morelia viridis). In: RW Henderson and R. Powell (Eds.): Biology of the Boas and Pythons. Eagle Mountain Publishing Company, Eagle Mountain., 2007: pp. 141-150. ISBN 978-0-9720154-3-4

Individual evidence

  1. a b c JG Walls 1998: The Living Pythons. TFH Publications, 1998: pp. 185-189
  2. D. Wilson: Foraging ecology and diet of an ambush predator: the Green Python (Morelia viridis). In: RW Henderson and R. Powell (Eds.): Biology of the Boas and Pythons. Eagle Mountain Publishing Company, Eagle Mountain., 2007: p. 145
  3. ^ A b D. Wilson: Foraging ecology and diet of an ambush predator: the Green Python (Morelia viridis). In: RW Henderson and R. Powell (Eds.): Biology of the Boas and Pythons. Eagle Mountain Publishing Company, Eagle Mountain., 2007: pp. 141-150
  4. Expert group on keeping terrarium animals in keeping with animal welfare. Federal Ministry of Food and Agriculture. 10. January. 1997 ( PDF )
  5. ^ Greg Maxwell: Morelia viridis - The Compendium. Chimaria Verlag, Frankfurt am Main 2005. ISBN 3-930612-79-8 .

Web links

Commons : Green tree python ( Morelia viridis )  - Collection of images, videos and audio files
This article was added to the list of excellent articles on March 7, 2006 in this version .