Cyclura rileyi

Cyclura rileyi
Conservation status
	; Endangered (IUCN 2.3)
	CITES Appendix I (CITES)
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Reptilia
Order:	Squamata
Suborder:	Iguania
Family:	Iguanidae
Genus:	Cyclura
Species:	C. rileyi
Binomial name
	Cyclura rileyi; Stejneger, 1903
Subspecies
	C. r. rileyiStejneger, 1903; C. r. cristata Schmidt, 1920; C. r. nuchalis Barbour & Noble, 1916;

Last updated December 22, 2024

Cyclura rileyi, commonly known as the Bahamian rock iguana or the San Salvador rock iguana, is a critically endangered species of lizard in the family Iguanidae. The species is native to three island groups in the Bahamas, and is in decline due to habitat encroachment by human development and predation by feral dogs and cats. There are three subspecies: the Acklins ground iguana (Cyclura rileyi nuchalis), the White Cay iguana (Cyclura rileyi cristata), and the nominotypical subspecies (Cyclura rileyi rileyi).

Taxonomy and etymology

The San Salvador rock iguana is an endangered species of lizard of the genus Cyclura in the family Iguanidae. First described by Leonhard Stejneger in 1903, it is known commonly in the Bahamas as simply "iguana".^[3]

Its specific name, rileyi, is a Latinized form of the surname of American ornithologist Joseph Harvey Riley,^[4] who collected the holotype.^[5]

Subspecies

As of 1975 two additional subspecific forms have been identified along with the nominal subspecies: the Acklins ground iguana (C. r. nuchalis) and the White Cay iguana (C. r. cristata).^[3] Together they are one of the most threatened species of all the West Indian rock iguanas and are described as critically endangered according to the current IUCN Red List.^[1]

Scientific name	Common Name	Distribution
Cyclura rileyi rileyi	Central Bahamian Rock Iguana, White Cay Ground Iguana	San Salvador, Bahamas
Cyclura rileyi cristata	White Cay iguana or Sandy Cay rock iguana	White Clay, the Bahamas
Cyclura rileyi nuchalis	Acklins ground iguana	Fish Cay and North Cay in the Acklins Bight, Bahamas

Anatomy and morphology

Measuring 300 to 390 mm (12 to 15 in) in snout-to-vent length (SVL) when full grown, the San Salvador rock iguana is a colorful lizard, the coloration varying between subspecies as well as between individual specimens. The lizard's back color can range from red, orange or yellow, to green, brown or grey, usually patterned by darker markings. The very brightest colors (red, orange, blue, or yellow) are normally only displayed by males and are more pronounced when at warmer body temperatures. Immature iguanas lack these bright colors, being either solid brown or grey with faint slightly darker stripes.^[1]

This species, like other species of Cyclura, is sexually dimorphic; males are larger than females, and have more prominent dorsal crests as well as larger femoral pores on their thighs, which are used to release pheromones.^[6]^[7]

Distribution

Once inhabiting all the large islands of the Bahamas, today C. rileyi is confined to six populations in small remote cays of three island groups: San Salvador Island, Acklins, and Exuma.^[8] A study in 1995 estimated there were between 426 and 639 specimens left in the wild, and that this number has likely been reduced since much of their habitat was destroyed in 1999 by Hurricane Floyd.^[9] The three island groups, each harboring its own subspecies, are on separate banks and were not connected during the last glacial period when water levels were 100 m (330 ft) lower than they are at present.^[8]

Diet

Like all Cyclura species, the San Salvador rock iguana's diet is primarily herbivorous, 95% of which comes from consuming leaves, flowers and fruits from 7 different plant species such as seaside rock shrub ( Rachicallis americana ), and erect prickly pear ( Opuntia stricta ).^[8] This diet is very rarely supplemented with insect larvae, crabs, slugs, dead birds and fungi.

Mating

Female San Salvador rock iguanas attain sexual maturity when they reach 20 cm (7.9 in) in length from snout to vent and weigh 300 g (11 oz). Males appear to mature at a slightly larger size, at approximately seven years of age.^[8]

Mating occurs in May and June, with clutches of 3-10 eggs usually laid in June or July, in nests excavated in pockets of earth exposed to the sun. Individuals are aggressively territorial from the age of about 3 months.

Conservation

While the island's natives often used iguanas as food and funerary offerings in pre-colonial times, man's largest-scale devastation to these animals was as a result of clear-cutting forests to create plantations as well as the introduction of non-native species.^[1] Introduced black rats, raccoons, feral dogs, mongoose, hogs, and cats have taken their toll on the population by direct predation, as have the larvae of a moth ( Cactoblastis cactorum ), introduced decades ago to the Caribbean, which are rapidly devastating prickly-pear cacti, an important food source for the iguanas.^[1] The Guana Cay population has been reduced to less than 24 individual animals.^[9]

Other threats by humans include tourists trampling iguanas' nests, iguanas contracting disease from eating human garbage, and illicit smuggling for the pet trade.^[1] As development increases on the islands and further isolates populations, these animals will be threatened by lack of gene flow between the cays.^[1]

As of August 2007^[update], no legal captive breeding programs exist outside of the Bahamas.^[1] The Bahamian government has refused to issue export permits for any rock iguanas.^[1] However, Ardastra Gardens in Nassau (New Providence Island, Bahamas) currently holds two juveniles and plans to implement a captive breeding program.^[1] A public relations campaign is planned to heighten awareness and appreciation among island residents for this endemic lizard.^[1]

Related Research Articles

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The blue iguana, also known as the Grand Cayman ground iguana, Grand Cayman blue iguana or Cayman Island rock iguana, is an endangered species of lizard which is endemic to the island of Grand Cayman. It was previously considered to be a subspecies of the Cuban iguana, Cyclura nubila, but in a 2004 article Frederic J. Burton reclassified it as a separate species because according to him the genetic differences discovered four years earlier between the different C. nubila populations warranted this interpretation. The blue iguana is one of the longest-living species of lizard.

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<span class="mw-page-title-main">Rhinoceros iguana</span> Species of iguana endemic to the Caribbean

The rhinoceros iguana is an endangered species of iguana that is endemic to the Caribbean island of Hispaniola and its surrounding islands. A large lizard, they vary in length from 60 to 136 centimetres, and skin colours range from a steely grey to a dark green and even brown. Their name derives from the bony-plated pseudo-horn or outgrowth which resembles the horn of a rhinoceros on the iguana's snout. It is known to coexist with the Ricord's iguana ; the two species are the only taxa of rock iguana to do so.

Ctenosaura bakeri, also known as the Utila spiny-tailed iguana, Baker's spinytail iguana, swamper or wishiwilly del suampo, is a critically endangered species of spinytail iguana endemic to the island of Utila, one of the Islas de la Bahía off the coast of Honduras in the Caribbean.

The northern Bahamian rock iguana is a species of lizard of the genus Cyclura that is found on Andros Island and the Exuma islands in the Bahamas. Its status on the IUCN Red List is vulnerable, with a wild population of less than 5,000 animals.

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The Acklins ground iguana, also commonly known as the Watling Island iguana, is an endangered subspecies of lizard of the genus Cyclura it is one of three subspecific forms of Cyclura rileyi in the family Iguanidae.

The Bahamian hutia or Ingraham's hutia is a small, furry, rat-like mammal found only in the Bahamas. About the size of a rabbit, it lives in burrows in forests or shrubland, emerging at night to feed on leaves, fruit, and other plant matter. It was believed extinct until rediscovery in 1964, and it remains the focus of conservation efforts. The Bahamian hutia is a member of the hutia subfamily (Capromyinae), a group of rodents native to the Caribbean, many of which are endangered or extinct.

The Andros Island iguana or Andros iguana is an endangered subspecies of Northern Bahamian rock iguana of the genus Cyclura that is found on Andros Island on the western edge of Grand Bahama. Its status is Endangered, with a wild population of 3,500 animals, and it can be found on the IUCN Red List.

Cyclura carinata bartschi, commonly known as Bartsch's iguana or the Booby Cay iguana, is a subspecies of lizard in the family Iguanidae. The subspecies is endemic to a single cay, Booby Cay, in The Bahamas.

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Cyclura rileyi cristata, the White Cay iguana or Sandy Cay rock iguana, is a critically endangered subspecies of lizard of the genus Cyclura native to a single cay in the Bahamas: White Cay located in the Southern Exumas.

Cyclura is a genus of lizards in the family Iguanidae. Member species of this genus are commonly known as "cycluras" and only occur on islands in the West Indies. Rock iguanas have a high degree of endemism, with a single species or subspecies originating on an individual island.

Cyclura pinguis, the Anegada rock iguana, Anegada ground iguana or stout iguana, is a critically endangered species of lizard of the genus Cyclura belonging to the family Iguanidae. The species can be found exclusively in the islands of Anegada and Guana. Historically, it inhabited the islands of Puerto Rico and Saint Thomas; however, the animal's original range has been greatly diminished over prehistory.

References

1 2 3 4 5 6 7 8 9 10 11 Carter, R.L.; Hayes, W.K. (1996). "Cyclura rileyi". IUCN Red List of Threatened Species . 1996: e.T6033A12351578. doi: 10.2305/IUCN.UK.1996.RLTS.T6033A12351578.en . Retrieved 16 November 2021.
↑ "Appendices | CITES". cites.org. Retrieved 14 January 2022.
1 2 Hollingsworth, Bradford D. (2004), "The Evolution of Iguanas: An Overview of Relationships and a Checklist of Species", Iguanas: Biology and Conservation, University of California Press, pp. 38–39, ISBN 978-0-520-23854-1
↑ "Riley, Joseph - Biography". Washington Biologists' Field Club; Patuxent Wildlife Research Center.
↑ Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). The Eponym Dictionary of Reptiles. Baltimore: Johns Hopkins University Press. xiii + 296 pp. ISBN 978-1-4214-0135-5. (Cyclura rileyi, p. 222).
↑ De Vosjoli, Phillipe; David Blair (1992), The Green Iguana Manual , Escondido, California: Advanced Vivarium Systems, ISBN 978-1-882770-18-2
↑ Martins, Emilia P.; Lacy, Kathryn (2004), "Behavior and Ecology of Rock Iguanas,I: Evidence for an Appeasement Display", Iguanas: Biology and Conservation, University of California Press, pp. 98–108, ISBN 978-0-520-23854-1
1 2 3 4 Hayes, William; Carter, Ronald; Cyril, Samuel; Thornton, Benjamin (2004), "Conservation of a Bahamian Rock Iguana, I", Iguanas: Biology and Conservation, University of California Press, pp. 232–243, ISBN 978-0-520-23854-1
1 2 Hayes, William K. (2003). "Can San Salvador's Iguanas and Seabirds Be Saved?". Department of Natural Sciences, Loma Linda University.{{cite journal}}: Cite journal requires |journal= (help)