Pale Litter Frog – Leptobrachella pallida – (Rowley, Tran, Le, Dau, Peloso, Nguyen, Hoang, Nguyen & Ziegler, 2016)

Science name: Leptobrachella pallida – (Rowley, Tran, Le, Dau, Peloso, Nguyen, Hoang, Nguyen & Ziegler, 2016)

Taxonomic:  Animalia>> Chordata>> Amphibia>> Anura >> Megophryidae >> pallida

Species status: Endemic ; IUCN status: EN (Endangered Species)

Description: Size and Physical Characteristics: Leptobrachella pallida is a small frog, with males ranging from 24.5 to 27.7 mm in snout-vent length (SVL). Females have not been documented in the original description. The frog has a distinct morphology, including a truncate snout and rounded tympanum that is smaller than the eye.

Coloration in Life: The frog exhibits a brown dorsal surface with dark interorbital bars and pale brown spots. The thighs, tibia, tarsus, and digits display dark brown transverse bars, and there is a darker brown line along the supratympanic ridge. The ventral surface is dark brown with white speckles, and the macroglands, such as the femoral and pectoral glands, are white. The iris has a copper upper half and a golden lower half with black reticulations.

Coloration in Preservative: After preservation, the dorsal color becomes paler, and the ventral surface remains a medium brown with faint white speckles. The macroglands become a creamy white color in preservative.

Distribution and habitat: Geographic Range: Leptobrachella pallida is known only from Gia Rich Mountain in Bidoup Nui Ba National Park, Lam Dong Province, central Vietnam. Although it is only documented from this specific area, similar habitats exist in neighboring Khanh Hoa and Ninh Thuan Provinces, suggesting the species may occur in these regions as well. The species has an estimated extent of occurrence (EOO) of 142 km².

Elevation: Individuals of this species have been recorded at elevations ranging from 1,644 to 1,681 meters above sea level.

Area: The species inhabits montane evergreen forests. It is typically found in leaf litter, rocky crevices, and clay holes along dry stream beds in these environments.

Habitat: Leptobrachella pallida thrives in evergreen montane forests. The species is strongly associated with streams and is thought to be dependent on high-quality forest habitats. The continued degradation of its habitat due to deforestation and agricultural expansion is a significant threat.

Behaviour and ecology: Reproductive Biology: While the reproductive biology of Leptobrachella pallida has not been directly observed, males have been recorded calling near streams, suggesting that it breeds in aquatic environments. The species is presumed to have a free-swimming larval stage, similar to other Leptobrachella species. Males were observed calling in June, indicating that this may be part of the breeding season.

Habitat Use: The species is nocturnal and closely tied to montane forest streams. Males are typically found calling from clay holes in dry stream beds or under leaf litter. Habitat loss and degradation, driven by deforestation and agriculture, have been observed in its range, which poses a significant risk to its survival.

Conservation and status: IUCN Red List Category and Criteria: Leptobrachella pallida is currently listed as Endangered under criteria B1ab(iii) due to its restricted range and the ongoing decline in habitat quality within its small range.

Population Trend: The population is believed to be in decline, primarily due to habitat loss. The number of mature individuals is unknown, but the population is likely severely fragmented.

Threats: The main threat to Leptobrachella pallida is habitat loss due to deforestation and agricultural expansion. The degradation of its montane forest habitat continues to reduce the available suitable environments for this species.

Conservation Actions: Protection of the remaining evergreen montane forests within the species’ range is critical for its conservation. Further research is necessary to better understand the species’ distribution, population size, and reproductive biology. Monitoring habitat quality and implementing forest conservation measures will be key to ensuring the survival of Leptobrachella pallida.