The
Lesser Antillean Iguana (
Iguana delicatissima) is a large arboreal
lizardLizards are a very large and widespread group of squamate reptiles, with nearly 5,000 species, ranging across all continents except Antarctica as well as most oceanic island chains...
endemic to the
Lesser AntillesThe Lesser Antilles, also known as the Caribbees, are part of the Antilles, which together with the Bahamas, the Turks and Caicos Islands, and Greater Antilles form the West Indies...
. It is one of two species of
lizardLizards are a very large and widespread group of squamate reptiles, with nearly 5,000 species, ranging across all continents except Antarctica as well as most oceanic island chains...
of the genus
IguanaIguana is a genus of lizard native to tropical areas of Central and South America and the Caribbean.. The genus was first described by Austrian naturalist Josephus Nicolaus Laurenti in his book Specimen Medicum, Exhibens Synopsin Reptilium Emendatam cum Experimentis circa Venena in 1768...
and is in severe decline due to habitat destruction, feral predators, hunting, and hybridization with its sister species the
Green iguanaThe green iguana or common iguana is a large, arboreal herbivorous species of lizard of the genus Iguana native to Central and South America...
. Successful captive breeding of this species has been limited to only two instances as most captive laid eggs tend to be infertile.
It is sometimes named the West Indian iguana, a name more commonly used for species of the genus
CycluraCyclura is a genus of lizards from the family Iguanidae. Members of this genus are known as "cyclurids" or more commonly as rock iguanas and only occur on islands in the West Indies...
.
Etymology and taxonomy
The generic name
Iguana is derived from
Iwana, a Spanish form of the
TainoThe Taínos are pre-Columbian inhabitants of the Bahamas, Greater Antilles, and the northern Lesser Antilles. It is believed that the seafaring Taínos are relatives of the Arawakan people of South America...
name for the species. Its specific name
delicatissima is
LatinLatin is an Italic language originally spoken in Latium and Ancient Rome. Through the Roman conquest, Latin spread throughout the Mediterranean and a large part of Europe...
for "extraordinary". The species was first officially described by Austrian
naturalistNaturalist may refer to:* A scholar or student of natural history, the science of the natural world; see also natural science. It may also refer to a Wildlife enthusiast or a Conservationist....
Josephus Nicolaus LaurentiJosephus Nicolaus Laurenti was an Austrian naturalist of Italian origin .Laurenti is considered the auctor of the class Reptilia through his authorship of Specimen Medicum, Exhibens Synopsin Reptilium Emendatam cum Experimentis circa Venena on the poisonous function of reptiles and amphibians...
in 1768.
Anatomy and morphology
The Lesser Antilles Iguana has a more blocky, shortened face than the Green Iguana and lacks the distinctive stripe pattern present along the Green Iguana's tail. The feature that most easily distinguishes these two species is the large, round scale that the Green iguana has below each ear hole but which the Lesser Antillean Iguana lacks.
The Lesser Antillean Iguana varies in color between different island populations, but the base color tends to be gray, with green splotching on the underside. They have large pale, ivory colored scales on their heads. The jowls of males are pink and the scales around the eyes are blue. Males also have femoral pores along each inner thigh that exude pheromones during breeding season. Males are larger than females and are 40cm (16in) long, with an 80cm (32in) tail when full-grown. Females are two-thirds this size.
Habitat and Distribution
The Lesser Antillean iguana is found in scrub woodland,
rainforestRainforests are forests characterized by high rainfall, with definitions setting minimum normal annual rainfall between 1750–2000 mm . The monsoon trough, alternately known as the intertropical convergence zone, plays a significant role in creating Earth's tropical rain forests.From 40 to 75%...
, and
mangroveMangroves are trees and shrubs that grow in saline coastal habitats in the tropics and subtropics – mainly between latitudes N and S. The saline conditions tolerated by various species range from brackish water, through pure seawater , to water of over twice the salinity of ocean seawater,...
throughout the
Lesser AntillesThe Lesser Antilles, also known as the Caribbees, are part of the Antilles, which together with the Bahamas, the Turks and Caicos Islands, and Greater Antilles form the West Indies...
on Saint Barth,
AnguillaAnguilla is a British overseas territory in the Caribbean, one of the most northerly of the Leeward Islands in the Lesser Antilles. It consists of the main island of Anguilla itself, approximately long by wide at its widest point, together with a number of much smaller islands and cays with no...
, St. Martin, St. Eustatius,
AntiguaAntigua is an island in the West Indies, in the Leeward Islands in the Caribbean region, the main island of the country of Antigua and Barbuda. Antigua means "ancient" in Spanish and was named by Christopher Columbus after a church in Spain, Santa Maria La Antigua — St. Mary the Ancient...
,
GuadeloupeGuadeloupe is an archipelago located in the eastern Caribbean Sea at , with a land area of 1,628 square kilometres . It is an overseas department of France. As with the other overseas departments, Guadeloupe is also one of the twenty-six regions of France and an integral part of the Republic...
,
DominicaDominica, officially the Commonwealth of Dominica, is an island nation in the Caribbean Sea. To the north-northwest lies Guadeloupe, to the southeast Martinique. Its size is and the highest point in the country is Morne Diablotins, which has an elevation of . The Commonwealth of Dominica has an...
, and
MartiniqueMartinique is an island in the eastern Caribbean Sea, with a land area of . It is an overseas department of France. To the northwest lies Dominica, to the south St Lucia, and to the southeast Barbados. As with the other overseas departments, Martinique is also one of the twenty-six regions of...
.
Ecology
Lesser Antillean iguanas are primarily
herbivoreA herbivore is an animal that is adapted to eat plants and not meat.Herbivory is a form of predation in which an organism consumes principally autotrophs such as plants, algae and photosynthesizing bacteria....
s, feeding on leaves, flowers, fruit, and growing shoots of upwards of 100 different species of plant. This presents a problem for
osmoregulationOsmoregulation is the active regulation of the osmotic pressure of an organism's fluids to maintain the homeostasis of the organism's water content; that is it keeps the organism's fluids from becoming too dilute or too concentrated. Osmotic pressure is a measure of the tendency of water to move...
: vegetable matter contains more
potassiumPotassium is the chemical element with the symbol K , atomic number 19, and atomic mass 39.0983. Potassium was first isolated from potash...
and has less nutritional content per gram, so more must be eaten to meet the animal's metabolic needs. Like most reptiles, Lesser Antillean iguanas are not capable of creating liquid urine more concentrated than their bodily fluids, like birds they excrete nitrogenous wastes as urate salts through a specially evolved
nasalAnatomically, a nose is a protuberance in vertebrates that houses the nostrils, or nares, which admit and expel air for respiration in conjunction with the mouth....
salt glandThe salt gland is an organ for excreting excess salts. It is found in elasmobranchs, seabirds, and some reptiles. In sharks, salt glands are found in the rectum, but in birds and reptiles, they are found in or on the skull, in the area of the eyes, nostrils or mouth. In crocodiles, the salt is...
. As a result, the iguanas have developed this lateral nasal gland to supplement renal salt secretion by expelling excess potassium and sodium chloride.
Conservation
The Lesser Antillean Iguana is a vulnerable species and is found on the
IUCN Red ListThe IUCN Red List of Threatened Species , founded in 1948, is the world's most comprehensive inventory of the global conservation status of plant and animal species. The International Union for the Conservation of Nature and Natural Resources is the world's main authority on the conservation...
. The Lesser Antillean iguana is legally protected from hunting throughout its range, but enforcement of these regulations is extremely difficult and therefore limited. Other threats include habitat loss to agriculture and development and the introduction of
feralA feral organism is one that has escaped from domestication and returned, partly or wholly, to a wild state. The introduction of feral animals or plants to their non-native regions, like any introduced species, can disrupt ecosystems and may, in some cases, contribute to extinction of indigenous...
predators such as
dogThe dog is a domesticated form of the Gray Wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The domestic dog has been one of the most widely kept working and companion animals in human history...
s,
catA feral cat is an unowned and untamed domestic cat. Feral cats are born in urban, suburban, or rural areas, and basically anywhere that people reside. They should not be confused with wildcats, as they are not wild animals. A stray cat , though unowned, still exhibits temperament similar to that...
s, and the
mongooseMongooses are a family of about 30 species of small carnivorans from southern Eurasia and mainland Africa. Four additional species from Madagascar in the subfamily Galidiinae, which were previously classified in this family, are also frequently referred to as "mongooses"...
.
The species greatest threat is from its own genus. The Green iguana has been introduced to the Lesser Antilles as an
invasive species'Invasive species' is a phrase with several definitions. The first definition expresses the phrase in terms of non-indigenous species that adversely affect the habitats they invade economically, environmentally or ecologically...
and directly competes with the Lesser Antillean Iguana for food and resources. In addition the Green iguana has been interbreeding with the Lesser Antillean Iguana and this hybridization has been the number one reason for decline on at least three of the islands: Les Iles des Saintes, Basse Terre (Guadeloupe) and St. Barthélemy.
Captive Lesser Antillean iguanas are currently kept at the Jersey Wildlife Preservation Trust,
Chester ZooChester Zoo is a zoological garden located in Cheshire in north west England. It was opened in 1931 by George Mottershead and his family, who used as a basis some animals reported to have come from an earlier zoo in Shavington. It is the one of the UK's largest zoos at...
,
Memphis ZooThe Memphis Zoo, located in Midtown Memphis, Tennessee, is home to more than 3,500 animals representing over 500 different species. Created in April 1906, the zoo has been a major tenant of Overton Park for more than 100 years. The land currently designated to the Memphis Zoo was defined by the...
and the
San Diego ZooThe World Famous San Diego Zoo in Balboa Park, San Diego, California is one of the largest and most progressive zoos in the world with over 4,000 animals of more than 800 species. It is also one of the few zoos in the world that houses the giant panda...
’s Center for Reproduction of Endangered Species. All individuals originate from the Commonwealth of Dominica. Breeding and keeping the species in captivity is difficult. Mating and egg laying have occurred at each institution but most of the eggs have been infertile, a single individual was successfully hatched at the Jersey Wildlife Preservation Trust in 1997 and in 2000 eight iguanas were hatched.
External links
- Iguana delicatissima at the Encyclopedia of Life
The Encyclopedia of Life is a free, online collaborative encyclopedia intended to document all of the 1.8 million living species known to science. It is compiled from existing databases and from contributions by experts and non-experts throughout the world...
- Saint Barth Fauna & Flora