Anolis grahami

Anolis grahami
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Subphylum: Vertebrata
Class: Reptilia
Order: Squamata
Suborder: Sauria
Infraorder: Iguania
Family: Polychrotidae
Genus: Anolis
Species: A. grahami
Binomial name
Anolis grahami
Gray, 1845
Synonyms
  • Anolis punctatus Gray, 1840 (non A. punctatus Daudin, 1802)
  • Anolis grahami Gray, 1845 (nomen substitutem)
  • Anolis iodurus Gosse, 1850
  • Anolis punctatissimus
    Hallowell, 1856
  • Norops grahami
    Schwartz & Henderson, 1988[2]

Anolis grahami, commonly called Graham's anole, the Jamaican anole or the turquoise anole, is a species of Anolis lizard originally endemic to the island of Jamaica, although it has since been introduced to Bermuda.[1] It is one of seven anole species found on Jamaica.

Etymology

The specific name, grahami, is in honor of Colonel James Duncan Graham (1799-1865) of the United States Army Corps of Topographical Engineers.[3]

Description

Anolis grahami has been called the world's most beautiful anole. Its upper body is usually a rich emerald or aquamarine while its trunk and legs are a bright deep blue. It has a bright orange dewlap. The first half of the tail is a deep blue, while the lower half is brilliant violet. Its underside is usually a light blue gray. Occasionally, especially in females and younger individuals, these colors may be somewhat muted, though still quite gaudy. Fully grown males can be exceptionally colorful; occasionally a pure turquoise blue lizard may be observed.

Mature male Anolis grahami can grow to a total length of 16 centimetres (6.3 in) and a snout-vent length (SVL) of 8 cm (3.1 in); females are smaller than males. During confrontations over territory or when threatened males may raise a small dorsal crest atop their heads.

Color change

Under the anole's skin are pigment cells called chromatophores responsible for its usual coloration. Underneath these pigment cells are specialized pigment cells called melanocytes which contain the pigment melanin, in response to changes in the lizards hormones these cells can expand and mask the ordinary pigment cells, resulting in a change to a darker coloration, thus the anole is capable of changing its hue from bright blue, to varying shades of brown or almost completely black when stressed.often the end of the tail,and sometimes the trunk,remains colored during a color change.These lizards also have the ability to change the color of only one half of their bodies.

Distribution and habitat

On Jamaica

Graham's anole in Jamaica

Anolis grahami is widespread across the island of Jamaica, where it can be found in all fourteen of the Jamaican parishes. The population of A. grahami is most diluted in the southern regions of the parishes of St. Catherine, Clarendon, and Manchester, though some A. grahami may be observed there too. On Jamaica only the endemic Anolis lineatopus is more widely distributed among the indigenous lizards and the lizards may be found in mountainous regions as well as lowlands.

On Bermuda

On Bermuda Anolis grahami is an introduced species and the first of three Anolis species to be introduced to the island. Before the introduction of A. grahami the Bermuda rock skink, Plestiodon longirostris, was the only lizard found on the island, but the Graham's anole is now the most widespread of the Bermudan lizards. Seventy-one A. grahami were introduced to the island in 1905 by a former agricultural director into a botanical garden with the intention of controlling the fruit fly population. Now it is out-competing the indigenous rock skink. Anolis grahami is listed as least concern by the IUCN.

Habitat

Anolis grahami is highly arboreal and may be found in the uppermost branches of trees throughout its range. It is also common to see it on the trunks of tall trees, as well in shrubbery, on fence posts, the walls of houses, and other man made objects. Due to its arboreal habits, this lizard can be quite difficult to observe in its natural habitat but is actually usually quite common across its range. This species fills a similar niche to Anolis lineatopus on Jamaica, where the two species are often in direct competition. In areas where the two species occur together A. lineatopus is commonly seen on the trunks and lower branches of trees, which are its preferred habitat, while A. grahami is often found in the treetops; this is similar to the relationship between Anolis sagrei and Anolis carolinensis in North America.

Behavior And Reproduction

mating

Like all Anolis species Graham's anole is highly territorial. When confronted by another male, a male Graham's anole will extend its bright orange dewlap and bob its head and abdomen up and down as if doing push-ups;if the intruding male does not withdraw then a chase will ensue and if one lizard is not chased away then a fight may occur. The victor gains rights to the territory. Their territorial threat display is also used by male lizards to attract females.

Reproduction

The reproductive habits of this species are not very well studied. The breeding season is believed to be from April to September. They lay their eggs in secluded places such as crevices inside decomposing logs or inside holes in the trunks of trees. Usually upwards of two small white eggs are laid.

Defense

Like most small lizards, Graham's anole has a wide range of predators, ranging from birds and cats to larger lizard species, including larger Graham's anoles. When it has sensed oncoming danger, the lizard's first reaction is to flee, usually upwards into the trees. If the lizard is captured or confronted, its first reaction will be to change its color from bright green to brown or black, indicating stress. It will also open its mouth and gape at the attacker while extending its dewlap in an attempt to intimidate its captor. If the lizard is picked up or handled, it may urinate on its captor in an attempt to discourage it. It may also bite, though its teeth are not large enough for it to pose any real danger to humans. Like most lizards, these anoles possess autotomic tails. If the lizard is captured or pursued, the end portion of the tail may break off and continue to move for several minutes, hopefully distracting its attacker and giving the lizard enough time to escape. Given time, the dislocated portion of the tail may be replaced by a stiff, cartilaginous rod.

Feeding

Like most anoles these lizards are ambush predators which prefer to sit and wait for prey and then capture it in quick bursts of speed. They will take prey including small arboreal insects such as butterflies or dragonflies. They will also take prey closer to the ground such as cockroaches or houseflies.

Subspecies

Two subspecies are recognized, including the nominotypical subspecies.[2]

Gallery

Juvenile A. g. aquarum

References

  1. 1 2 de Quieroz K, Mayer GC. (2010). "Anolis grahami". IUCN Red List of Threatened Species. Version 2009.2. International Union for Conservation of Nature. Retrieved April 24, 2013.
  2. 1 2 "Anolis grahami ". The Reptile Database. www.reptile-database.org.
  3. Beolens B, Watkins M, Grayson M. 2011. The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN 978-1-4214-0135-5. (Anolis grahami, p. 105).

Further reading

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