Rock-face Litter Frog – Leptobrachella petrops – (Rowley, Dau, Hoang, Le, Cutajar & Nguyen, 2017)

Science name: Leptobrachella petrops – (Rowley, Dau, Hoang, Le, Cutajar & Nguyen, 2017)

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

Species status: Endemic ; IUCN status: NT (Near Threatened)

Description:

Size and Physical Characteristics: Like other species in the Leptobrachella genus, Leptobrachella petrops is a small frog, though detailed size measurements for this specific species have not been widely documented.

Coloration in Life: While detailed coloration information for this species is limited, it shares characteristics typical of Leptobrachella frogs, such as cryptic dorsal patterns suited for camouflage in rocky forest environments.

Coloration in Preservative: Information on coloration changes after preservation is not yet documented, but as with many small amphibians, colors are likely to dull and patterns may become less distinct.

Distribution and habitat:

Geographic Range: Leptobrachella petrops is known from northern Vietnam, specifically in Lai Chau, Tuyen Quang, and Ha Giang Provinces. The species has a relatively wide estimated extent of occurrence (EOO) of 27,903 km², though its actual range may extend into neighboring areas of northwestern Vietnam and potentially southern China. Surveys in these adjacent areas may reveal additional populations.

Elevation: This species inhabits elevations between 234 and 1,350 meters above sea level, typically within montane regions.

Area: The species occupies evergreen montane forests and is closely associated with rocky streams within these environments. It is commonly found in secondary forests as well. The ongoing degradation of forests within its known range poses a significant threat to the species.

Habitat: Leptobrachella petrops thrives in montane evergreen forests, particularly along rocky streams. During breeding seasons, males have been observed calling from rocks, stream banks, and vegetation adjacent to these streams. The species is likely forest-dependent, as it has not been observed in non-forest habitats, and habitat degradation due to agricultural expansion is a major concern.

Behaviour and ecology:

Reproductive Biology: Although the eggs and larvae of Leptobrachella petrops remain unknown, it is presumed to breed in streams, similar to other species within its genus. Males are known to call during the breeding season, typically from rocks and vegetation along streams. The species likely has a free-swimming larval stage, similar to other Leptobrachella species whose reproductive behavior has been studied.

Habitat Use: Leptobrachella petrops primarily inhabits rocky montane streams within evergreen forests. Males are more commonly observed during the breeding season in May, while females are typically found farther from water on limestone karsts during non-breeding periods. The species is highly dependent on forested areas, and its presence is strongly tied to high-quality habitat conditions.

Conservation and status:

IUCN Red List Category and Criteria: Leptobrachella petrops is currently listed as Near Threatened under criteria B1b(iii) due to its restricted range, continuing habitat degradation, and ongoing decline in the extent and quality of its forest habitat.

Population Trend: The population is believed to be decreasing, primarily due to habitat loss driven by agricultural activities. Fragmentation of the population is also suspected, though exact numbers of mature individuals remain unknown.

Threats: The primary threat to Leptobrachella petrops is the destruction and degradation of its montane forest habitat. Agricultural expansion, deforestation, and habitat fragmentation are the leading causes of habitat loss, reducing both the area and quality of the forest. The ongoing decline in suitable habitat poses a significant risk to the species’ long-term survival.

Conservation Actions: Efforts to conserve Leptobrachella petrops should focus on protecting the remaining montane forests within its range. Given that it is highly dependent on forested habitats, preventing further deforestation and promoting habitat restoration are crucial. Further research is also needed to understand the species’ population size, distribution, and reproductive biology better. Enhanced monitoring of its habitat could provide valuable data for future conservation actions.