Taxonomy
- Kingdom: Animalia
- Phylum: Chordata
- Class: Amphibia
- Order: Anura
- Family: Bombinatoridae
- Genus: Barbourula
- Species: Barbourula busuangensis
- Authority: Taylor & Noble, 1924
Common names
Philippine flat‑headed frog, Palawan flat‑headed frog, Busuanga jungle toad, Busuanga disk‑tongued toad, Philippine aquatic frog.
Description
Barbourula busuangensis is a large, heavily aquatic frog. It possesses a dorsoventrally flattened body, with the eyes and nostrils positioned on the top of the head. The species lacks external tympani. Both fore‑ and hind limbs are robust and muscular, and the digits of the hands and feet are fully webbed. The skin is covered with fine tubercles and the dorsal coloration is dark greenish‑black with faint pale green hatching and spotting on the hind limbs.
Distribution and habitat
The species is endemic to the western Philippines, occurring on the islands of Busuanga, Culion, Balabac, and Palawan. It inhabits clear, fast‑flowing, unpolluted streams within lowland tropical forests, typically at elevations below 800 m (2,600 ft) above sea level. The frogs are primarily aquatic, often floating on the water surface but quickly diving and seeking shelter when disturbed.
Reproduction
Little is known about the breeding biology of B. busuangensis. Tadpoles have not been observed in the wild. Pregnant females have been found with large, unpigmented eggs, leading researchers to hypothesize possible direct development (i.e., development without a free‑living tadpole stage), though this remains unconfirmed.
Conservation status
The International Union for Conservation of Nature (IUCN) classifies Barbourula busuangensis as Near Threatened. The assessment notes that the species occurs at a limited number of fragmented locations, with declining populations. Principal threats include habitat loss and degradation due to agricultural expansion, quarrying, mining, and pollution of streams from agricultural runoff.
References
- IUCN SSC Amphibian Specialist Group (2018). Barbourula busuangensis. The IUCN Red List of Threatened Species 2018: e.T23900A58474888.
- Frost, D. R. (2019). Barbourula busuangensis Taylor and Noble, 1924. Amphibian Species of the World, an Online Reference. American Museum of Natural History.
All information presented is based on verified encyclopedic sources.