Jackson's chameleon

Jackson's chameleon was described by Belgian-British zoologist George Albert Boulenger in 1896.{{cite journal|last=Boulenger|first=George Albert|author-link=George Albert Boulenger|year=1896|title=Description of a new Chameleon from Uganda|journal=Annals and Magazine of Natural History |series=Sixth Series|volume=17|issue=101|page=376|doi=10.1080/00222939608680383|url=https://zenodo.org/record/2086913}} (Chamaeleon jacksonii, new species).

The generic name, Trioceros, is derived from the Greek τρί- (tri-) meaning "three" and κέρας (kéras) meaning "horns".{{cite book|author1-link=Henry Liddell |last1=Liddell |first1=HG |author2-link=Robert Scott (philologist) |last2=Scott |first2=R |year=1980|title=Greek-English Lexicon, Abridged Edition|publisher=Oxford, United Kingdom: Oxford University Press|isbn=978-0-19-910207-5|url-access=registration|url=https://archive.org/details/lexicon00lidd}} 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.{{cite book| title=The Chameleon Handbook|first=François|last= Le Berre|author2=Bartlett, Richard D.| publisher =Barron's Educational Series|year=2009 |page=3|isbn=978-0-7641-4142-3 }}{{cite book | author1-link=Bo Beolens |last1=Beolens |first1=Bo |author2-link=Michael Watkins (zoologist) |last2=Watkins |first2=Michael |author3-link=Michael Grayson |last3=Grayson |first3=Michael |year=2011 |title=The Eponym Dictionary of Reptiles |location=Baltimore |publisher=Johns Hopkins University Press |pages=296 [132] |isbn=978-1-4214-0135-5}}

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".[http://dictionary.reference.com/browse/chameleon Dictionary.com entry for "chameleon"]

The following three subspecies are recognized as being valid, including the nominate subspecies.

• T. j. jacksonii {{small|(Boulenger, 1896)}} – Jackson's chameleon
• T. j. merumontanus {{small|(Rand, 1958)}} – dwarf Jackson's chameleon
• T. j. xantholophus {{small|(Eason, Ferguson & Hebrard, 1988)}} – yellow-crested Jackson's chameleon

Nota bene: A trinomial authority in parentheses indicates that the subspecies was originally described in a genus other thanTrioceros.

File:Tjxantholophus.JPG]]

Jackson's chameleon is an arboreal lizard. It is native to woodlands and wet forests at altitudes of {{convert|1600|to|2440|m|ft|abbr=on}} in south-central Kenya and northern Tanzania.Waring GH (1996) [http://www.hear.org/alienspeciesinhawaii/waringreports/chameleon.htm Preliminary Study of the Behavior and Ecology of Jackson's Chameleon of Maui, Hawaii.] Southern Illinois University. Retrieved 11 November 2014. In these areas, the rainfall is seasonal but exceeds {{convert|127|cm|in|abbr=on}} per year. Day temperatures are typically {{convert|16|-|27|C|F|abbr=on}}, and night temperatures are typically {{convert|4|-|18|C|F|abbr=on}}. 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. Jackson's chameleon is more widespread in Kenya, where it is even found in wooded areas of some Nairobi suburbs.

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.{{cite web|url=http://www.reportapest.org/pestlist/chajac.htm|title=Jackson's chameleon (Chamaeleo jacksonii)|publisher=Hawaii Biodiversity Information Network|access-date=2013-09-19}}Holland BS, Montgomery SL, Costello V (2010). "A reptilian smoking gun: first record of invasive Jackson’s chameleon (Chamaeleo jacksonii) predation on native Hawaiian species". Biodiversity and Conservation 19 (5): 1437–1441. {{doi|10.1007/s10531-009-9773-5}}.Chiaverano LM, Holland BS (2014). "Impact of an invasive predatory lizard on the endangered Hawaiian tree snail Achatinella mustelina: a threat assessment". Endangered Species Research 24: 115–123. {{doi|10.3354/esr00589}}.Kraus F, Preston D (2012). "Diet of the invasive lizard Chamaeleo jacksonii (Squamata: Chamaeleonidae) at a wetforest site in Hawaii". Pacific Science 66: 397–404. [http://dlnr.hawaii.gov/hisc/files/2013/02/Chamaeleo-jacksonii-Volcano-diets.pdf PDF]. This subspecies has also been introduced to Florida. In Hawaii, it is found mainly at altitudes of {{convert|100|to|1000|m|ft|abbr=on}} in wet, shady places. 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. This has been done to prevent opportunists from willfully establishing further feral animal populations to capture and sell them.

{{More citations needed section|date=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,{{cite web |url=http://www.animalspot.net/jacksons-chameleon.html |title=Jackson's Chameleon |website=Animal Spot |date=2 December 2015 |access-date=May 30, 2018 }} 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 {{convert|38|cm|in|abbr=on}} and females up to {{convert|25|cm|in|abbr=on|0}}, but more typical lengths are {{convert|15|to|25|cm|in|abbr=on|0}}. 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.{{cite magazine |url=http://www.reptilesmagazine.com/Care-Sheets/Lizards/Jacksons-Chameleon/ |title=Jackson's Chameleon Care Sheet |first=Linda |last=Davison |access-date=May 30, 2018 |magazine=Reptiles }}

File:Starr-120312-3686-Psidium guajava-branches with Jacksons chameleon-Enchanting Floral Gardens of Kula-Maui (24841956880).jpg

Jackson's chameleon lives primarily on a diet of small insects. It also preys on centipedes, isopods, millipedes, spiders, lizards, small birds, and snails (Achatinella mustelina) in their native habitat. It is considered to be a cruise forager, as it forages on the go instead of laying in wait.{{Cite journal |last1=Chiaverano |first1=Luciano |last2=Wright |first2=Melissa |last3=Holland |first3=Brenden |year=2014 |title=Movement Behavior is Habitat Dependent in Invasive Jackson's Chameleons in Hawaii |url=https://www.jstor.org/stable/43287475 |journal=Journal of Herpetology |volume=48 |issue=4 |pages=471–479|doi=10.1670/13-150 |jstor=43287475 |url-access=subscription }}

There is a threat of devastating impact by introduced invasive Jackson's chameleons to native ecosystems in Hawaii, South Africa, the Marshal Islands, Morro Bay, California, Texas, and the Florida Keys. It was found with mainly insects in its stomachs: planthoppers (genus Oliarus), grasshoppers (genus Banza), casebearing caterpillars (genus Hyposmocoma), beetles (genus Oodemas), dragonflies (genus Pantala) and others. It also preys on land snails in Hawaii, including species from genera Achatinella, Auriculella, Lamellidea, and Philonesia, as well as Oxychilus alliarius. It swallows whole snails, including the shells. Jackson's chameleons introduced to Hawaii are a substantial threat to native biodiversity of invertebrates and a serious threat especially to endemic species, such as critically endangered O'ahu tree snails (genus Achatinella).

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.

File:Chamaeleo jacksonii.jpg]]

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;{{cite web |url=http://animaldiversity.org/accounts/Chamaeleo_jacksonii/ |title=Jackson's chameleon |website=Animal Diversity Web |publisher=University of Michigan Museum of Zoology |access-date=May 30, 2018 |first=Heather |last=Kundinger }}{{cite journal| last1=Hughes | first1=D.F. | last2=Blackburn | first2=D.G. | year=2020 | title=Evolutionary origins of viviparity in Chamaeleonidae | journal=Journal of Zoological Systematics and Evolutionary Research | volume=58 | issue=1 | pages=284–302 | doi=10.1111/jzs.12328 | doi-access=free }} 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.{{Cite web|title=Jackson's Chameleon Care|url=https://chameleonacademy.com/jacksons-chameleon-care/|website=Chameleon Academy|date=14 September 2019 |language=en-US|access-date=2020-05-30}}

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.{{cite web |url=http://exoticpets.about.com/od/chameleons/p/jacksoncham.htm |archive-url=https://web.archive.org/web/20060204015734/http://exoticpets.about.com/od/chameleons/p/jacksoncham.htm |url-status=dead |archive-date=February 4, 2006 |title=How to Care for Jackson's Chameleons |website=The Spruce Pets |author=Lianne McLeod |date=7 February 2020 }} Jackson's chameleon requires an array of different food options to remain healthy.

{{Reflist|30em}}

• [https://web.archive.org/web/20101214150217/http://caresheets.net/lizards/jacksons-chameleon.html Jackson's Chameleon Care Information at Caresheets.net]
• [http://www.hear.org/species/chamaeleo_jacksonii/ Chamaeleo jacksonii information from HEAR]
• [http://www.hear.org/alienspeciesinhawaii/waringreports/chameleon.htm Preliminary study of the behavior and ecology of Jackson's chameleons of Maui, Hawaii] (Dr. George H. Waring, Dept. of Zoology, Southern Illinois University)

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Category:Trioceros

Category:Reptiles described in 1896

Category:Taxa named by George Albert Boulenger

Category:Lizards of Africa

Category:Reptiles of Kenya

Category:Reptiles as pets

Category:Reptiles of Tanzania