''Geckolepis megalepis'' is a

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 ...

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 ar ...

found in the limestone

karst Karst is a topography formed from the dissolution of soluble rocks such as limestone, dolomite, and gypsum. It is characterized by underground drainage systems with sinkholes and caves. It has also been documented for more weathering-resistant ro ...

formations of northern

Madagascar Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa ...

. It is the first addition to the '' Geckolepis''

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

since 1942. This species of gecko has the largest

scales Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number w ...

of any known gecko and can detach them as a defence mechanism when a predator attacks, leaving the predator with a mouthful of scales rather than itself; a character it shares with all other members of the

'' Geckolepis''. Its scales were reported to come away with greater ease than its congeners.

Distribution and conservation status

''Geckolepis megalepis'' was described from Ankarana National Park. It is thought to be restricted to the ''tsingy''

formations of this park. It was proposed to be

Near Threatened A near-threatened species is a species which has been categorized as "Near Threatened" (NT) by the International Union for Conservation of Nature as that may be vulnerable to endangerment in the near future, but it does not currently qualify fo ...

in its original description, due to ongoing anthropogenic degradation of its habitat, but probable resilience to these changes.

Defense mechanism

''Geckolepis megalepis'' has developed remarkably large scales (hence the specific epithet 'megalepis', from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

words for "very large scales") and an extreme variation of integumentary autotomy. Myofibroblastic contraction in a pre-formed splitting-zone sheds the keratinized epidermis, connective tissues and subcutaneous fat tissue. Typical integumentary autotomy in squamates only includes the keratinized epidermis, thus distinguishing the de-scalation methods of ''G. megalepis''. Scarless regeneration of the entire denuded integument occurs within several weeks, resuming superficial scalation patterns. The skin, being so easily shed, became difficult for scientists attempting captures or studies without causing structural damage to the epidermis. Eventually they were able to come up with a way to collect them, and discovered that the species' scales are dense and mineralized (though not recognized by the authors as osteoderms). Dermolytic scale autotomy in ''G. megalepis'' has remained poorly recorded thus far, only being witnessed in an anti-predator setting with a '' Blaesodactylus'' gecko''.'' Further documentation of the autotomy process is required to better understand the origins of regeneration and associated morphological characters in ''Geckolepis''.

Ecology

Little to nothing is known of the ecology of ''Geckolepis megalepis'', except that it is nocturnal,

arboreal Arboreal locomotion is the Animal locomotion, locomotion of animals in trees. In habitats in which trees are present, animals have evolved to move in them. Some animals may scale trees only occasionally, but others are exclusively arboreal. Th ...

, and insectivorous.

References

Geckolepis Endemic fauna of Madagascar Lizards of Africa Reptiles described in 2017 Taxa named by Mark D. Scherz {{gecko-stub