Darevsky’s Ground Skink – Scincella darevskii – Nguyen, Ananjeva, Orlov, Rybaltovsky & Böhme, 2010

Science name: Scincella darevskii – Nguyen, Ananjeva, Orlov, Rybaltovsky & Böhme, 2010

Taxonomic:  Animalia>> Chordata>> Reptilia>> Squamata >> Scincidae >> darevskii

Species status: Endemic ; IUCN status: LC (Least Concern)

Description:

Physical Characteristics:

Size: Large skink, measuring up to 88.6 mm in snout-vent length (SVL).
Scales: Prefrontals are separated, and there are 5 supraoculars. The species has 28 midbody scale rows and 62 paravertebral scales, which are not widened. Dorsal scales are smooth and arranged in 6 rows across the back.
External Features: The external ear opening is present, with 3 lobules on the anterior margin of the tympanum. There is a prominent light dorsolateral stripe running from the neck to the hindlimbs.
Coloration and Appearance:
The dorsum and tail base are bronze-brown, with a light dorsolateral stripe extending from the neck to the hindlimbs. The upper lateral region has a dark brown stripe running from the nostril to the anterior corner of the eye and from the posterior corner of the eye to the base of the tail. Another light stripe runs from the nostril below the eye, continuing past the tympanum to the anterior groin.

Distribution and habitat:

Elevation:
The type locality of Scincella darevskii, commonly known as Darevsky’s Ground Skink, is situated at an elevation of 1,450 meters above sea level in Tuan Giao District, Dien Bien Province, Vietnam.

Area:
This species is currently known only from its type locality in Tuan Giao District, within Dien Bien Province. Its natural habitat includes evergreen forests and secondary forests that have regenerated after shifting cultivation. The skink is endemic to Vietnam, and no records of it exist outside of this region.

Habitat:
Scincella darevskii is primarily found in evergreen forests and regenerating forests at lower elevations up to 800 meters. The species typically inhabits rocky crevices and leaf litter in forest floors, where it seeks cover and forages. It is a diurnal species that feeds on insects and other small invertebrates. The species shows a preference for undisturbed forests and is sensitive to habitat loss and degradation.

Behaviour and ecology:

Lifestyle:
Scincella darevskii is a diurnal species, active during the daytime and typically found on the forest floor or in rock crevices. It is primarily insectivorous, feeding on insects and other arthropods found in the leaf litter and under rocks. The species is shy and retreats quickly when disturbed.

Reproduction:
This skink is oviparous, laying two eggs at a time. Eggs are typically laid in tree hollows or under leaf litter, providing a moist and protected environment for incubation.

Conservation and status:

IUCN Red List Category and Criteria:
Scincella darevskii is currently listed as Data Deficient on the IUCN Red List, as it is known only from a single specimen and there is insufficient information to assess its conservation status accurately. The most recent assessment was conducted in 2017.

Population Trend:
The population trend of Scincella darevskii is unknown. Since it has only been recorded from one specimen, no data are available on its population stability or potential decline.

Threats:
The primary threat to Scincella darevskii is likely habitat loss, particularly due to deforestation and the degradation of evergreen and regenerating forests. Although the species can tolerate secondary forests, it may be vulnerable to ongoing deforestation and habitat fragmentation, which could reduce suitable habitats for this species.

Conservation Actions:
Currently, there are no specific conservation actions in place for Scincella darevskii. Additional research is necessary to determine its population size, distribution, and habitat requirements. Protecting the forested areas where the species occurs is crucial for its conservation, and ensuring the preservation of both primary and secondary forest habitats would help mitigate habitat loss.

Etymology
The species name darevskii honors the Russian herpetologist Ilya S. Darevsky (1924–2009), who made significant contributions to the study of reptiles, particularly in Vietnam and other parts of Southeast Asia.