La Palma Giant Lizard
Encyclopedia
The La Palma Giant Lizard (Gallotia auaritae) is a giant lacertid historically living in the island of La Palma
La Palma
La Palma is the most north-westerly of the Canary Islands. La Palma has an area of 706 km2 making it the fifth largest of the seven main Canary Islands...

 (Canary Islands
Canary Islands
The Canary Islands , also known as the Canaries , is a Spanish archipelago located just off the northwest coast of mainland Africa, 100 km west of the border between Morocco and the Western Sahara. The Canaries are a Spanish autonomous community and an outermost region of the European Union...

, Spain
Spain
Spain , officially the Kingdom of Spain languages]] under the European Charter for Regional or Minority Languages. In each of these, Spain's official name is as follows:;;;;;;), is a country and member state of the European Union located in southwestern Europe on the Iberian Peninsula...

); its habitat ranged from sea level up to altitudes of 800 m.

It probably lives in xerophytic vegetation and is presumably an egg-laying species.

Long believed extinct in historic times, there were sightings (including photographic evidence) of a large lacertid in 2007 which may possibly correspond to this species.

Taxonomy

Working on fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...

 and subfossil
Subfossil
Subfossil refers to remains whose fossilization process is not complete, either for lack of time or because the conditions in which they were buried were not optimal for fossilization....

 evidence, this giant lizard was originally described as a subspecies
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...

 of the El Hierro Giant Lizard (Mateo et al. 2001). Later, it was elevated to full species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 rank (Afonso & Mateo 2003). Specimen remains from La Palma assigned to G. goliath
Gallotia goliath
Gallotia goliath is an extinct giant lizard species from the island of Tenerife of the Canary Islands, Spain. This reptile lived before the arrival of humans. It was described by the German herpetologist Robert Mertens. It is believed that it grew to at least three feet long...

seem to belong to this taxon instead; if this is correct, they indicate that the average size of this species had been decreasing over the last millennia, possibly due to humans preferring to hunt larger lizards (Barahona et al. 2000). The recently sighted individual of the La Palma Giant Lizard was slight more than 30 cm (~1 ft) long and had an estimated age of four years. New expeditions to the area of the rediscovery are planned in the hope of finding more individuals and possibly a breeding population.

However, scientist have not had the chance of studying any alive animal and the present fossil and subfossil material of G. auaritae does not allow for sufficiently detailed analyses of its phylogenetic status. Probably it belongs to the simonyi clade
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...

 like the other giant Gallotia species from the western islands, but whether it actually was as close to G. simonyi as presumed remains unverified. The reason for this is also that it was only discovered after the present species' description that G. goliath was not another local representative of G. simonyi, as was previously assumed, but a more distantly related species (Maca-Meyer 2003).

Status

Its decline may have started 2000 years ago with the arrival of humans on La Palma. Until its recent sightings, it was believed to have become extinct in the last 500 years. The main causes of this presumed extinction
Extinction
In biology and ecology, extinction is the end of an organism or of a group of organisms , normally a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and recover may have been lost before this point...

 were believed to have been introduced cats, consumption by the original human population of the Canary islands
Guanche
Guanche may refer to:*Guanches, an aboriginal people of the Canary Islands*Guanche language, extinct language, used to be spoken by the Guanches until the 16th or 17th century...

, and habitat
Habitat
* Habitat , a place where a species lives and grows*Human habitat, a place where humans live, work or play** Space habitat, a space station intended as a permanent settlement...

 destruction for agriculture
Agriculture
Agriculture is the cultivation of animals, plants, fungi and other life forms for food, fiber, and other products used to sustain life. Agriculture was the key implement in the rise of sedentary human civilization, whereby farming of domesticated species created food surpluses that nurtured the...

. It is not the only lizard from the Canary Islands to have been considered extinct only to be rediscovered later: This happened with other giant lizards of the Canary Islands, like the El Hierro Giant Lizard
El Hierro Giant Lizard
Gallotia simonyi is a species of lacertid that can be found on the island of El Hierro, one of the Canary Islands. The species was once present throughout much of the island and on the small offshore Roque Chico de Salmor, but is now confined to a few small areas of cliff with sparse vegetation...

 and La Gomera Giant Lizard
La Gomera Giant Lizard
The La Gomera Giant Lizard is a lacertid species that can be found on the island of La Gomera, one of the Canary Islands....

s (rediscovered 1974 and 1999, respectively); the somewhat smaller Tenerife Speckled Lizard
Tenerife Speckled Lizard
The Tenerife Speckled Lizard, Gallotia intermedia, is a recently-discovered lacertid of Tenerife in the Canary Islands...

was only discovered for the first time in 1996.

At this point, not a single living individual could have been captured and any remaining population, if existing, is assumed to be tiny.

External links

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