The La Gomera giant lizard (''Gallotia bravoana'') is a lacertid (wall lizard)

species In biology, a species is the basic unit of 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 the appropriate s ...

that can be found on the island of

La Gomera La Gomera () is one of Spain's Canary Islands, located in the Atlantic Ocean off the coast of Africa. With an area of , it is the third smallest of the eight main islands of this archipelago. It belongs to the province of Santa Cruz de Tene ...

, one of the Canary Islands. It is easily distinguishable from any other member of ''Gallotia'' by the intense white colour that covers its neck, chest and area around the mouth, in spectacular contrast to its dark brown back. This lizard is generally diurnal and mostly

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpar ...

, and grows up to half a metre long (head and body long). The females lay a single clutch annually of three to seven eggs on average. Its population trend has actually been increasing since 2001.

Status and conservation

Apparent La Gomera giant lizards are listed in reports on La Gomera up to the 19th century, but not thereafter. The species was originally described from subfossil remains in 1985, presumably having gone extinct by then. Spanish biologists led by Juan Carlos Rando rediscovered this species in 1999. The biologists found only six living individuals. The current population of the La Gomera giant lizard consists of (2004) 90 individuals remaining in the wild, and a captive stock of about 44 animals. This species is now only known from two separate inaccessible cliffs 2 km apart, close to the Valle Gran Rey. The La Gomera giant lizard is thought to have once ranged throughout much of La Gomera and in many habitat types. Nowadays it is found in the Parque Rural de Valle Gran Rey, and the present range is less than one

hectare The hectare (; SI symbol: ha) is a non-SI metric unit of area equal to a square with 100- metre sides (1 hm2), or 10,000 m2, and is primarily used in the measurement of land. There are 100 hectares in one square kilometre. An acre is ...

and is restricted to dry cliffs with sparse vegetation. The La Gomera Giant Lizard is listed as Critically Endangered by the

IUCN Red List The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...

. The species historically declined through

overgrazing Overgrazing occurs when plants are exposed to intensive grazing for extended periods of time, or without sufficient recovery periods. It can be caused by either livestock in poorly managed agricultural applications, game reserves, or nature res ...

, hunting, and predation by feral

cat The cat (''Felis catus'') is a domestic species of small carnivorous mammal. It is the only domesticated species in the family Felidae and is commonly referred to as the domestic cat or house cat to distinguish it from the wild members of ...

s and rats. Nowadays the main threats are predation by feral cats, and rock falls within its restricted range. The species is protected by international legislation, and a species recovery plan is in place. On La Gomera, a captive breeding programme has been established in order to increase the number of individuals. To ensure the survival of the remaining populations and facilitate eventual reintroductions, the feral cat population around the species' range will need to be controlled.

Taxonomy and systematics

In his scientific description, the German zoologist R. Hutterer referred the subfossil remains from La Gomera to two subspecies of ''

Gallotia simonyi ''Gallotia simonyi'', also known as Simony's lizard, is a species of lacertid (wall lizard) that was found on many of the Canary Islands. The species was once present throughout much of the islands, but one of the two subspecies is extinct, whil ...

'' with the differences being size related. He named these ''Gallotia simonyi bravoana'' and ''Gallotia simonyi gomerana''. Bischoff (1998) synonymized them to a single

taxon In biology, a taxon ( back-formation from '' taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular n ...

. Barbadillo ''et al.'' (1999) decided for ''bravoana'' when they elevated the taxon to species rank. Nogales ''et al.'' (2001) concurred as regards species status, but used ''Gallotia gomerana''. Following the ruling of the International Commission on Zoological Nomenclature, ''gomerana'' is a junior synonym or ''bravoana''. It is not unequivocally accepted that it does constitute a distinct species; however, in all likelihood, ''G. simonyi'' is its closest living relative.

References

External links

* lacerta.de
''Gallotia bravoana''
image gallery. Retrieved 2007-FEB-25. https://www.iucnredlist.org/species/61502/12493034#population {{Taxonbar, from=Q2309290 Gallotia Giant Lizard Reptiles of the Canary Islands Reptiles described in 1985