C. j. xantholophus is locally abundant in the cool montane rainforests of Kenya, Tanzania and Hawaii (introduced). They may reach a total length of 12-14 inches with a SVL of 4-6 inches. Adults may weigh anywhere from 80 over 150 grams for a large, gravid female. Specimens are only moderately aggressive toward keepers but quite aggressive toward conspecifics.

Characteristically described as a miniature Triceratops, this is a striking, lime green chameleon. Some have attractive yellow highlights while others sport a bluish tinge to their green coloration. Stress coloration is dark brown, often with a pattern of lighter colored diamonds along the flanks. When cold or under severe stress, a uniform dark brown is typical. Some specimens have been reported to live as long as 9 years although 5-6 years is more typical. The casque is low, lacks occipital lobes and projects a few millimeters behind the head. A prominent dorsal crest runs the length of the trunk. Gular striations may be apparent, particularly in juvenile animals.

Gender Identification: Males have three prominent horns. As the names of these horns imply, two originate in front of the eyes (i.e., preocular horns) and the third, rostral horn, from the snout. (The word rostral is derived from the Latin word for "beak.") Females of C. j. xantholophus have only small, vestigial horns. The difference is quite obvious in adults and a small difference may be seen in juveniles as young as 8-12 weeks.

Being native to montane rainforests, these chains require cool temperatures and high humidity. Basking temperatures should be 80-85ºF with a night time temperature drop of at least 10ºF degrees. Night time temperatures into the 40F range or even lower are well tolerated as long as the animal has the ability to warm up to 70ºF or higher during the day. Two-three mistings per day, each lasting 3-5 minutes should be supplemented by a drip system. An ultrasonic humidifier is useful in maintaining proper humidity and is highly recommended. As with most chameleons, glass aquaria should be avoided. In addition to making it difficult to provide the proper temperature gradient, glass aquaria do not permit the air flow needed to prevent respiratory infections. Although they readily accept a variety of prey items, C. jacksonii xantholophus is sensitive to oversupplementation and exhibits significant edema, particularly in the cervical region if vitamin supplements are used more than once a week.

As with most chameleons, males are highly aggressive toward conspecifics and must be housed separately. There are reports of successful group housing of females but only in very large walk-in types of cages. Solitary housing is highly recommended for all members of this species.

Females give birth to 10-30 live young after a gestation of 5-10 months. As is true of most chameleons, females of this species are reportedly able to store sperm, thus accounting for their reported ability to deliver several clutches from a single mating. Despite this common wisdom, there are surprisingly few documented cases of this phenomenon in captive specimens.

Ten - 30 live young are born in a single clutch. One clutch per year seems to be the rule but 2 clutches per year may be possible. As with most live bearers the babies are quite delicate and should be sorted and housed by size frequently to minimize the social stress that may inhibit their growth and contribute to a high infant mortality. The young feed eagerly on Drosophila hydeii and later on pinhead crickets. Adequate supplies of productive D. hydeii cultures must be on hand when a clutch is expected. Babies are less tolerant of heat and low humidity than are the adults and slightly lower temperatures are recommended. When misting the babies, care should be taken to direct the spray at the plant leaves rather than the babies themselves as a droplet of water on its snout may asphyxiate such a tiny animal. Sexual maturity is reached in 5-6 months although most breeders suggest waiting to breed a female until she 9-12 months old.

For two excellent articles on the ecology and behavior of Jackson's chameleons in Hawaii see the articles by Dr. George H. Waring and James M. Ko

Contributed by E. Pollak

References
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Davison, Linda J. 1997. Chameleons: Their Care and Breeding. Hancock House Publishers, Blaine, WA.
De Vosjoli, P. 1998. Preliminary obsevations on intraspecies communication in the Jackson's chameleon. Chameleon Information Network # 28, 16-25.
De Vosjoli, P. and Ferguson, G. 1995. Care and Breeding of Chameleons. Advanced Vivarium Systems, Santee, CA.
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Le Berre, F. 1994. The New Chameleon Handbook. Barron's Educational Series.
Martin, J., 1992. Masters of Disguise: A Natural History of Chameleons. Facts On File, Inc., New York, NY.
Necas, P. 1999. Chameleons: Nature's Hidden Jewels. Krieger Publishing Company, Malabar, FL.
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Spawls, S., Howell, K., Drewes, R., and Ashe, J. 2002. A Field Guide to the Reptiles of East Africa. Academic Press, New York.