Jackson's chameleon | |
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Male | |
Female | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Reptilia |
Order: | Squamata |
Suborder: | Iguania |
Family: | Chamaeleonidae |
Genus: | Trioceros |
Species: | T. jacksonii |
Binomial name | |
Trioceros jacksonii | |
Map highlighting countries inhabited by the Jackson's chameleon | |
Synonyms [3] | |
Jackson's chameleon (Trioceros jacksonii), also known commonly as Jackson's horned chameleon, the three-horned chameleon, and the Kikuyu three-horned chameleon, is a species of chameleon, a lizard in the family Chamaeleonidae. The species is native to East Africa, and introduced to Hawaii, Florida, and California. [1] [3] [4] [5] [6] There are three recognized subspecies.
Jackson's chameleon was described by Belgian-British zoologist George Albert Boulenger in 1896. [2]
The generic name, Trioceros , is derived from the Greek τρί- (tri-) meaning "three" and κέρας (kéras) meaning "horns". [7] This is in reference to the three horns found on the heads of males.
The specific name, jacksonii, is a Latinized form of the last name of English explorer and ornithologist Frederick John Jackson, who was serving as the first Governor of Kenya at the time of Boulenger's description. [8] [9] : 132
The English word chameleon (also chamaeleon) derives from Latin chamaeleō, a borrowing of the Ancient Greek χαμαιλέων (khamailéōn), a compound of χαμαί (khamaí) "low to the ground" and λέων (léōn) "lion". The Greek word is a calque translating the Akkadian nēš qaqqari, "ground lion". [10]
The following three subspecies are recognized as being valid, including the nominate subspecies. [3]
Nota bene : A trinomial authority in parentheses indicates that the subspecies was originally described in a genus other thanTrioceros.
Jackson's chameleon is native to woodlands and forests at altitudes of 1,600 to 2,440 m (5,250 to 8,010 ft) in south-central Kenya and northern Tanzania. [4] [11] In these areas, the rainfall is seasonal but exceeds 127 cm (50 in) per year. Day temperatures are typically 16–27 °C (61–81 °F), and night temperatures are typically 4–18 °C (39–64 °F). [11] In Tanzania, it is known only from Mount Meru in the Arusha Region, which is the home of the relatively small endemic subspecies T. j. merumontanus. [4] Jackson's chameleon is more widespread in Kenya, where it is even found in wooded areas of some Nairobi suburbs. [4]
The subspecies T. j. xantholophus (native to the Mount Kenya region) was introduced to Hawaii in 1972 and has since established populations on all main islands and has become an invasive species there. [12] [13] [14] [15] This subspecies has also been introduced to Florida. [5] In Hawaii, it is found mainly at altitudes of 100 to 1,000 m (330 to 3,280 ft) in wet, shady places. [5] Historically this population was the primary source of Jackson's chameleons for the exotic pet trade in the United States, but exports from Hawaii are now illegal. [5] This has been done to prevent opportunists from willfully establishing further feral animal populations to capture and sell them. [15]
This section needs additional citations for verification .(November 2010) |
Jackson's chameleon is sometimes called the three-horned chameleon because males possess three brown horns: one on the nose (the rostral horn) and one above each superior orbital ridge above the eyes (preocular horns), somewhat reminiscent of the ceratopsid dinosaur genus Triceratops . The females generally have no horns, [16] or instead have traces of the rostral horn (in the subspecies T. j. jacksonii and T. j. merumontanus). The coloring is usually bright green, with some individual animals having traces of blue and yellow, but like all chameleons, it changes color quickly depending on mood, health, and temperature.
Adult males reach a total length (including tail) of up to 38 cm (15 in) and females up to 25 cm (10 in), but more typical lengths are 15 to 25 cm (6 to 10 in). [4] It has a saw-tooth shaped dorsal ridge and no gular crest. It attains sexual maturity after five months. The lifespan is variable, with males generally living longer than females.
The largest subspecies of Jackson's chameleon is T. j. xantholophus, which has been captively bred since the 1980s. [17]
Jackson's chameleon lives primarily on a diet of small insects. It also preys on centipedes, isopods, millipedes, spiders, lizards, small birds, and snails in their native habitat. [13]
There is a threat of devastating impact by introduced invasive Jackson's chameleons to native ecosystems in Hawaii. [13] They were found with mainly insects in their stomachs: planthoppers Oliarus , grasshoppers Banza , casebearing caterpillars Hyposmocoma , beetles Oodemas , dragonflies Pantala [13] and others. [15] Holland et al. (2010) [13] proved that they also prey on snails in Hawaii. [13] Their prey includes land snails Achatinella , Auriculella , Lamellidea , Philonesia , [13] Oxychilus alliarius . [15] They are swallowing whole snails (including shells). [13] Jackson's chameleons introduced to Hawaii are a substantial threat to native biodiversity of invertebrates [15] and a serious threat especially to endemic species, such as critically endangered O'ahu tree snails (genus Achatinella). [13] [14]
T. jacksonii is less territorial than most species of chameleons. Males will generally assert dominance over each other through color displays and posturing in an attempt to secure mating rights, but usually not to the point of physical fights.
Most chameleons are oviparous, but Jackson's chameleon and several other highland species in the genus Trioceros are ovoviviparous, giving birth to offspring soon after they are ready to hatch from their egg sac; [18] [19] eight to thirty live young are born after a five- to six-month gestation. The subspecies T. j. merumontanus gives birth to five to ten live young. [20]
In captivity, Jackson's chameleon requires high humidity, and is in general very needy of colder temperatures during the night. Too much heat, or excessive humidity, can cause eye infections and upper respiratory infections in this species. In captivity, Jackson's chameleon can be expected to live between five and ten years. [21]
Chameleons or chamaeleons are a distinctive and highly specialized clade of Old World lizards with 200 species described as of June 2015. The members of this family are best known for their distinct range of colours, being capable of colour-shifting camouflage. The large number of species in the family exhibit considerable variability in their capacity to change colour. For some, it is more of a shift of brightness ; for others, a plethora of colour-combinations can be seen.
Chamaeleo is a genus of chameleons in the family Chamaeleonidae. Most species of the genus Chamaeleo are found in sub-Saharan Africa, but a few species are also present in northern Africa, southern Europe, and southern Asia east to India and Sri Lanka.
Achatinella is a tropical genus of colorful land snails in the monotypic Achatinellidae subfamily Achatinellinae.
Trioceros johnstoni, known commonly as Johnston's chameleon, Johnston's three-horned chameleon, and the Ruwenzori three-horned chameleon, is a species of chameleon, a lizard in the family Chamaeleonidae. The species is endemic to highlands in the Albertine Rift in central Africa. It reaches up to 30 cm (12 in) in total length. Only the adult male has three horns. The female is hornless.
Trioceros is a genus of lizards in the family Chamaeleonidae, the chameleons, native to lowlands and highlands in the African mainland, ranging from Ethiopia south to Mozambique and west as far as Ghana. Trioceros was considered a subgenus of the genus Chamaeleo until 2009, when it was elevated to full genus level.
Trioceros melleri, with the common names Meller's chameleon and giant one-horned chameleon, is the largest species of chameleon from the African mainland.
Kinyongia tavetana, the Kilimanjaro two-horned chameleon or Kilimanjaro blade-horned chameleon, is a species of chameleon in the genus Kinyongia. It is native to forests, woodlands, well-wooded gardens and plantations in the highlands of southern Kenya and northern Tanzania. Its type locality is Mount Kilimanjaro, but it is also known from Chyulu Hills and Mount Meru to the Pare Mountains.
The graceful chameleon is a species of chameleon native to sub-Saharan Africa. It is commonly around a foot long. Because of its abundance, it is heavily exploited by the pet trade.
Owen's chameleon, also commonly known as Owen's three-horned chameleon, is a species of lizard in the family Chamaeleonidae. The species is native to forests in central Africa. Named after British naval officer and explorer William Fitzwilliam Owen, it was first described in 1831 by the naturalist John Edward Gray, and is the type species of the genus Trioceros.
Kinyongia boehmei, the Taita blade-horned chameleon, Böhme's two-horned chameleon and Dwarf fischer's chameleon, is species of chameleon, a lizard in the family Chamaeleonidae, found only in the Taita Hills of southeastern Kenya. It is the smallest species in the East African "two-horned chameleon" group and until 2008 it was generally considered a part of K. tavetana.
Kinyongia vosseleri, also known commonly as the Usambara two-horned chameleon and Vosseler's blade-horned chameleon, is an endangered species of lizard in the family Chamaeleonidae. The species is endemic to Tanzania.
The four-horned chameleon is a species of chameleon, a lizard in the family Chamaeleonidae. The species is native to highland areas in western Cameroon and southeastern Nigeria.
Trioceros ellioti, also known commonly as Elliot's chameleon, Elliot's groove-throated chameleon, and the montane side-striped chameleon, is a species of lizard in the family Chamaeleonidae. The species is indigenous to Africa.
Trioceros feae, also known commonly as the Bioko montane chameleon and Fea's chameleon, is a species of lizard in the family Chamaeleonidae. The species is endemic to the island of Bioko.
Trioceros fuelleborni, also known commonly as the flapjack chameleon, the Ngosi Volcano chameleon, and the Poroto three-horned chameleon, is a species of lizard in the family Chamaeleonidae. The species is endemic to Tanzania.
Trioceros goetzei, also known commonly as Goetze's chameleon, Goetze's whistling chameleon, and the Ilolo chameleon, is a species of lizard in the family Chamaeleonidae. The species is native to eastern Africa. There are two recognized subspecies.
Trioceros harennae, also known commonly as the Harenna hornless chameleon, is a species of lizard in the family Chamaeleonidae. The species is endemic to Ethiopia. There are two recognized subspecies.
Trioceros werneri, the Wemer's chameleon or Wemer's three-horned chameleon, is a species of chameleon that is endemic to forests and nearby gardens at altitudes of 1,700–2,600 m (5,600–8,500 ft) in the Eastern Arc Mountains of Tanzania. The adult male has three distinct "horns", whereas the female has no or only a single short horn on the nose. Like many Trioceros species of highlands, the female T. werneri does not lay eggs, but instead gives birth to live young, typically 15–20 at a time.
Chameleon ranching is the action of releasing chameleons into an area with the intent of establishing them and later collecting them to sell for a profit. This type of ranching has existed since the 1970s, but has become more widespread around the early 2000s. It is an example of people intentionally releasing a foreign species.
Chamaeleo intermedius is an extinct species of chameleon from the Miocene of Kenya. It was given its name based on the fact that it shares traits with both species of the genus Chamaeleo and those of Trioceros, which at the time were placed in the same genus. This belief that it was an intermediate form was however rejected by later research.