''Sphaerodactylus callocricus'', also known as the beautifully ringed sphaero, rough-banded sphaero or rough-banded least gecko, 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 ...

lizard Lizards are a widespread group of squamate reptiles, with over 7,000 species, ranging across all continents except Antarctica, as well as most oceanic island chains. The group is paraphyletic since it excludes the snakes and Amphisbaenia alt ...

in the family

Sphaerodactylidae The Sphaerodactylidae are a family of geckos (Gekkota) distributed in North America, Central America, South America, and the Caribbean, as well as in Southern Europe, North Africa, the Middle East, and into Central Asia. The family contains 12 li ...

. It 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 elsew ...

to the

Dominican Republic The Dominican Republic ( ; es, República Dominicana, ) is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean region. It occupies the eastern five-eighths of the island, which it shares wit ...

Taxonomic history

This species was described in 1976 by Albert Schwartz, who received multiple specimen collected by Louis G. Thompson in the

Samaná peninsula The Samaná Península is a peninsula in Dominican Republic situated in the province of Samaná. The Samaná Peninsula is connected to the rest of the state by the isthmus of Samaná; to its south is Samaná Bay. The peninsula contains many beache ...

during malacological surveys. The type locality is "2.9 mi. (4.6 km) S

Las Galeras Las Galeras is a Municipal district in the town Santa Bárbara de Samaná, Samaná province in the northeast coast of Dominican Republic. It is located at the eastern end of the Samaná Peninsula, on the Rincón Bay that is found between Cabrón ...

Samaná Province Samaná () is a Provinces of the Dominican Republic, province of the Dominican Republic in the Samaná Peninsula located in the eastern region. Its Capital (political), capital is Samaná (town), Santa Bárbara de Samaná, usually known as Samaná ...

, República Dominicana".

Etymology

The name "''callocricus''" has a

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 ...

origin, and bears reference to the banded color pattern of this

. The

specific epithet In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bot ...

can be translated to "beautifully ringed", with "''kallos''" meaning "beautiful" and "''krikos''" meaning "ring".

Distribution and habitat

This species is endemic to the

on eastern Dominican Republic. Within the peninsula, this species is not common, and is associated with karstic forests, where it can be encountered under stones, boulders,

leaf litter Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent ...

and other debris. Specimen can also be seen during the day active on the forest floor.

Morphology

''S. callocricus'' is a moderately sized species of ''Sphaerodactylus'', with relatively large, keeled and

imbricate Aestivation or estivation is the positional arrangement of the parts of a flower within a flower bud before it has opened. Aestivation is also sometimes referred to as praefoliation or prefoliation, but these terms may also mean vernation: the ar ...

dorsal scales In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publis ...

. Members of this species are conspicuously banded, with dark transverse bands on a pale, yellowish gray background color. A very large scapular patch is present, with paired

ocelli A simple eye (sometimes called a pigment pit) refers to a form of eye or an optical arrangement composed of a single lens and without an elaborate retina such as occurs in most vertebrates. In this sense "simple eye" is distinct from a multi-l ...

at its center. The head pattern consists on a series of stripes, blotches or bands forming a "W" shape. There is little

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...

in this species, and both adult males, females and juveniles resemble each other. The pattern in juveniles tends to be much more contrasting, and it gradually fades in intensity as the specimen matures.

Conservation

According to the most recent

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 ...

assessment, ''S. callocricus'' is listed as critically endangered (CR).The distribution of ''S. callocricus'' is very restricted, and the species has been estimated to occupy a range of less than 100 km². Tourism development, small scale agriculture and pasture expansion are the main

threats A threat is a communication of intent to inflict harm or loss on another person. Intimidation is a tactic used between conflicting parties to make the other timid or psychologically insecure for coercion or control. The act of intimidation for co ...

affecting this species. ''S. callocricus'' needs

old growth An old-growth forestalso termed primary forest, virgin forest, late seral forest, primeval forest, or first-growth forestis a forest that has attained great age without significant disturbance (ecology), disturbance, and thereby exhibits un ...

karstic forests to thrive, and these ecosystems are disappearing from the Samaná at a fast rate. As they are very sensitive to habitat perturbations, this species is threatened by human activities. The home range of the species is likewise drastically reduced, and recent surveys have failed to find surviving populations of this species in historical locations where habitat has been modified.

Images

File:Intact kartic forest in Samana 136757131 10165281253250131 8673179491435373054 o.jpg, Intact habitat of ''Sphaerodactylus callocricus''. File:Samana slash and burn agriculture 137535401 10165281253505131 7213273231808207397 o.jpg, Former habitat of ''S. callocricus'' after being destroyed by human activities.

References

{{Taxonbar, from=Q3493109 Sphaerodactylus Reptiles of the Dominican Republic Endemic fauna of the Dominican Republic Reptiles described in 1976 Taxa named by Albert Schwartz (zoologist)