Murphy’s water skink – Tropidophorus murphyi – Hikida, Orlov, Nabhitabhata & Ota, 2002

Science name: Tropidophorus murphyi – Hikida, Orlov, Nabhitabhata & Ota, 2002

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

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

Description: Physical Characteristics:

Size: Adult males reach a snout-vent length (SVL) of 62.4 to 85.1 mm, with a tail length of 101 mm (tail tip lost in holotype). Adult females are larger, with an SVL of 79.3 to 95.6 mm and a tail length of 106.5 to 110.4 mm.
Head Scales: The scales on the upper head are smooth. The frontonasal scale is undivided, and the prefrontals are in contact with each other. Parietals do not contact posteriorly, and there are 2 loreals, with the anterior one usually divided.
Facial Features: The species has 6 supralabial scales and 5–6 infralabials, with the first one being the longest.
Body Scales: Midbody scale rows number between 30–32, with 55–67 paravertebral scales and 55–56 ventral scales.
Tail Scales: At the position of the tenth subcaudal, there are 12–13 scale rows, with 20–25 subdigital lamellae under the fourth toe.
Limbs: The limbs are well-developed and covered with smooth scales.
Coloration and Appearance:

The dorsum and base of the tail are dark grey with light transverse bands.
The body is flattened and adapted to its saxicolous lifestyle, blending well with the surrounding rocky environment.

Distribution and habitat: Elevation:
Tropidophorus murphyi, or Murphy’s Water Skink, is found at elevations between 700 and 750 meters above sea level.

Area:
This species is endemic to northern Vietnam, specifically in Quang Thanh Village, Nguyen Binh District, Cao Bang Province. The type locality is at coordinates 22°37’43”N, 105°54’46”E.

Habitat:
Tropidophorus murphyi inhabits subtropical/tropical moist lowland forests and rocky areas, particularly in humid, rocky environments near streams. This saxicolous (rock-dwelling) and presumably nocturnal species relies on the moist crevices in rocks along steep slopes, often in areas surrounded by brush, to hide during the day. The species is well adapted to this specific environment and may be highly vulnerable to drought conditions. It has been recorded living in sympatry with Tropidophorus sinicus.

Behaviour and ecology: Lifestyle:
Tropidophorus murphyi is a nocturnal and saxicolous species, spending most of its time hidden in moist rocky crevices. It likely comes out to bask on mossy rocks and find food, but retreats quickly when threatened. It is also ovoviviparous, giving birth to live young in litters of 3–5 neonates, each measuring about 28 mm.

Diet:
The skink’s diet mainly consists of small invertebrates found near streams in its rocky habitat.

Conservation and status: IUCN Red List Category and Criteria:
Tropidophorus murphyi is listed as Least Concern on the IUCN Red List (2017) due to its relatively stable population and presence in a protected area.

Population Trend:
The current population trend is unknown, and further research is needed to assess the population size and dynamics.

Threats:

Habitat Loss: The species may face threats from deforestation, habitat degradation, and human development in its limited range.
Environmental Changes: Being highly dependent on humid, rocky streamside habitats, the species is vulnerable to drought and water pollution.
Conservation Actions:

Protected Areas: The skink’s known habitat is within the boundaries of protected areas, providing some level of security against habitat destruction.
Further Research: More surveys are needed to better understand the species’ distribution, population size, and ecological requirements, especially regarding its vulnerability to climate change and habitat disturbance.