The Stephen's Island gecko (''Toropuku stephensi''), also known commonly as the Cook Strait striped gecko, Stephen's sticky-toed gecko, and the striped 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 ...

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 ...

in the

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 ...

''Toropuku'' in the

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

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 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 ...

New Zealand New Zealand ( mi, Aotearoa ) is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and over 700 smaller islands. It is the sixth-largest island count ...

Taxonomy and etymology

The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

of ''T. stephensi'' is in the collection of the

Museum of New Zealand Te Papa Tongarewa The Museum of New Zealand Te Papa Tongarewa is New Zealand's national museum and is located in Wellington. ''Te Papa Tongarewa'' translates literally to "container of treasures" or in full "container of treasured things and people that spring fr ...

.'The

name, ''Toropuku'', derives from the Maori word for "secret" or "stealthy". www.reptile-database.org. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

, ''stephensi'', refers to Stephens Island, New Zealand.Beolens, Bo; Watkins, Michael; Grayson, Michael (2011). ''The Eponym Dictionary of Reptiles''. Baltimore, Maryland: Johns Hopkins University Press. xiii + 296 pp. . (''Hoplodactylus stephensi'', p. 253). ''Toropuku'' was believed to be a

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispec ...

genus until the 2020 description of '' Toropuku inexpectatus.''

Habitat

The preferred natural

habitat In ecology, the term habitat summarises the array of resources, physical and biotic factors that are present in an area, such as to support the survival and reproduction of a particular species. A species habitat can be seen as the physical ...

s of ''T. stephensi'' are coastal

forest A forest is an area of land dominated by trees. Hundreds of definitions of forest are used throughout the world, incorporating factors such as tree density, tree height, land use, legal standing, and ecological function. The United Nations' ...

and

shrubland Shrubland, scrubland, scrub, brush, or bush is a plant community characterized by vegetation dominated by shrubs, often also including grasses, herbs, and geophytes. Shrubland may either occur naturally or be the result of human activity. It m ...

, at altitudes from sea level to . ''T. stephensi'' is known from several small islands in the

Cook Strait Cook Strait ( mi, Te Moana-o-Raukawa) separates the North and South Islands of New Zealand. The strait connects the Tasman Sea on the northwest with the South Pacific Ocean on the southeast. It is wide at its narrowest point,McLintock, A H, ...

between

North Island The North Island, also officially named Te Ika-a-Māui, is one of the two main islands of New Zealand, separated from the larger but much less populous South Island by the Cook Strait. The island's area is , making it the world's 14th-largest ...

and

South Island The South Island, also officially named , is the larger of the two major islands of New Zealand in surface area, the other being the smaller but more populous North Island. It is bordered to the north by Cook Strait, to the west by the Tasman ...

of New Zealand. It was first described from Stephens Island, and occurs in higher densities on

Maud Island Maud Island, also called Te Hoiere in the Māori language, is one of the larger islands in the Marlborough Sounds on the northern tip of the South Island of New Zealand, with a total area of . Fauna Maud Island is an important predator free natu ...

. In 2019, a population was also established on Puangiangi Island. A discontinuous population found in the

Coromandel Peninsula The Coromandel Peninsula ( mi, Te Tara-O-Te-Ika-A-Māui) on the North Island of New Zealand extends north from the western end of the Bay of Plenty, forming a natural barrier protecting the Hauraki Gulf and the Firth of Thames in the we ...

of North Island was given its own species, ''T. inexpectatus'', in 2020.

Reproduction

''T. stephensi'' is

viviparous Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the m ...

and has a low reproductive rate, with females giving birth to 1-2 young every other year. Sexual maturity is estimated to be at six years, and total life expectancy exceeds 16 years.

Conservation status

As of 2012 the Department of Conservation (DOC) classified the Stephen's Island gecko as Nationally Vulnerable under the

New Zealand Threat Classification System The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand. The system was developed because the IUCN Red List, a similar conservation status system, had some ...

. The

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

lists ''T. stephensi'' as

endangered An endangered species is a species that is very likely to become extinct in the near future, either worldwide or in a particular political jurisdiction. Endangered species may be at risk due to factors such as habitat loss, poaching and inva ...

, as it occupies limited areas at a small population density. Mainland populations in particular (now ''T. inexpectatus'') are under pressure from introduced cats, rodents, and

stoats The stoat (''Mustela erminea''), also known as the Eurasian ermine, Beringian ermine and ermine, is a mustelid native to Eurasia and the northern portions of North America. Because of its wide circumpolar distribution, it is listed as Least Conc ...

. Urban development and a higher density of cats intensifies this pressure near the town of

Coromandel Coromandel may refer to: Places India *Coromandel Coast, India **Presidency of Coromandel and Bengal Settlements ** Dutch Coromandel *Coromandel, KGF, Karnataka, India New Zealand *Coromandel, New Zealand, a town on the Coromandel Peninsula *Coro ...

. In 2020, ''T. stephensi'' was split into two species, with the Coromandel peninsula populations placed into ''T. inexpectatus''. A re-evaluation of ''T. stephensi'''s conservation status is necessary, as the species is now believed to be restricted to the three islands in the Cook Strait. Despite the small area occupied by the Cook Strait island populations, they seem to be stable and protected from introduced predators, as the islands are nature reserves which can only be accessed by permit.

References

External links