''Rhacodactylus leachianus'', commonly known as the New Caledonian giant gecko, Leach's giant gecko, Leachianus Gecko, or simply Leachie, is a large

species In biology, a species is the basic unit of Taxonomy (biology), classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of ...

gecko Geckos are small, mostly carnivorous lizards that have a wide distribution, found on every continent except Antarctica. Belonging to the infraorder Gekkota, geckos are found in warm climates throughout the world. They range from . Geckos are ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideal ...

Diplodactylidae The Diplodactylidae are a family in the suborder Gekkota (geckos), with over 150 species in 25 genera. These geckos occur in Australia, New Zealand, and New Caledonia. Diplodactylids are the most ecologically diverse and widespread family of geck ...

. The species, which was first described by

Georges Cuvier Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French naturalist and zoologist, sometimes referred to as the "founding father of paleontology". Cuvier was a major figure in na ...

in 1829, is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found else ...

New Caledonia ) , anthem = "" , image_map = New Caledonia on the globe (small islands magnified) (Polynesia centered).svg , map_alt = Location of New Caledonia , map_caption = Location of New Caledonia , mapsize = 290px , subdivision_type = Sovereign st ...

Taxonomy

The specific name, ''leachianus'', is in honor of English

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the animal kingdom, including the structure, embryology, evolution, classification, habits, and d ...

William Elford Leach William Elford Leach FRS (2 February 1791 – 25 August 1836) was an English zoologist and marine biologist. Life and work Elford Leach was born at Hoe Gate, Plymouth, the son of an attorney. At the age of twelve he began a medical apprenti ...

. Historically, there have been three recognized

subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...

of ''R. leachianus'' (including the

nominotypical subspecies In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics ( morphology), but that can successfully interbreed. Not all specie ...

): ''R. l. aubrianus'', ''R. l. henkeli'' (first described by Seipp and Obst in 1994), and ''R. l. leachianus''. However, based on recent molecular data, no populations of ''R. leachianus'' are granted subspecies status at the present time.

Description

Diplodactylidae - Rhacodactylus leachianus

''R. leachianus'' is the largest

extant Extant is the opposite of the word extinct. It may refer to: * Extant hereditary titles * Extant literature, surviving literature, such as ''Beowulf'', the oldest extant manuscript written in English * Extant taxon, a taxon which is not extin ...

gecko in the world and is considered an example of

island gigantism Island gigantism, or insular gigantism, is a biological phenomenon in which the size of an animal species isolated on an island increases dramatically in comparison to its mainland relatives. Island gigantism is one aspect of the more general "i ...

. ''R. l. leachianus'', or the Grande Terre locality, is capable of growing 14-17″ (36-43cm) long, while ''R. l. henkeli'', or the Isle of Pines locality, is capable of growing 9-12" (23-30cm) long. It has a heavy body, loose skin, and a small, stumpy tail. It is variable in color, coming in shades of mottled green, gray, and brown, sometimes with highlights of white, orange, and/or pink.''Rhacodactylus leachianus''.
Australian Reptile Park.

Distribution and habitat

''R. leachianus'' is found in all of the southern and eastern portions of the main island of New Caledonia, as well as on several of the smaller islands in the group.

Biology

''R. leachianus'' is an arboreal species, living in trees. It is nocturnally active, but may bask in the morning sun. It eats a diet of insects, spiders, small vertebrates, fruit, nectar, and sap. Adult females of ''R. leachianus'' lay two eggs at a time, having up to 10 clutches per year. ''R. leachianus'' can make a loud growling noise, and local people call it "the devil in the trees". Like many chameleons, New Caledonian Geckos can change the color of their skin. This is due to pigment containing cells called

chromatophores Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast, ...

. Depending on the amount of sunlight, their skin may be lighter or darker. This is a form of

camouflage Camouflage is the use of any combination of materials, coloration, or illumination for concealment, either by making animals or objects hard to see, or by disguising them as something else. Examples include the leopard's spotted coat, the b ...

and can help the gecko blend into their environments. These giant geckos also can climb vertically up glass surfaces. This is due to adhesive pads on their feet called lamellas, which are made up of tiny hairs which increase friction force when applied to surfaces.

Folklore

Some of the indigenous

Kanak people The Kanak ( French spelling until 1984: Canaque) are the indigenous Melanesian inhabitants of New Caledonia, an overseas collectivity of France in the southwest Pacific. According to the 2019 census, the Kanak make up 41.2% of New Caledonia ...

of New Caledonia fear Leach's giant gecko. This is because of an old superstition which purports that it has the ability to cling to a person's body and pull out that person's soul.

Conservation status

Populations of the species ''R. leachianus'' have likely been reduced by habitat destruction and degradation. This process is still a threat to the species. It also faces predation by

introduced species An introduced species, alien species, exotic species, adventive species, immigrant species, foreign species, non-indigenous species, or non-native species is a species living outside its native distributional range, but which has arrived there ...

such as cats and various rodents. It is also poached. It can be electrocuted when it travels along power lines. This species is protected and it lives in several nature reserves.

In captivity

The New Caledonian giant gecko is occasionally kept as a pet. Individuals in the pet trade are propagated with

captive breeding Captive breeding, also known as captive propagation, is the process of plants or animals in controlled environments, such as wildlife reserves, zoos, botanic gardens, and other conservation facilities. It is sometimes employed to help species t ...

; wild populations are protected. This species may live over 20 years in captivity.Guide to the Largest Geckos in the World.
Stephen Cemelli.

References

{{DEFAULTSORT:Rhacodactylus Leachianus Rhacodactylus Geckos of New Caledonia Reptiles described in 1829 Taxa named by Georges Cuvier