Fejervarya cancrivora, commonly known as the Crab-eating frog, belongs to the family Dicroglossidae (Nadia et al., 2020). It is also known as the Asian brackish frog, Mangrove frog and “Katak paya bakau” in Malay. This frog can be found in Southeast Asia, especially in Thailand and Malaysia (Peninsular Malaysia, Sabah and Sarawak). It was also recorded at the Tasik Bera Ramsar Site (Norsham et al., 2000) and Ulu Paip Recreational Forest in Kedah (Shahriza & Ibrahim, 2014). It inhabits mangrove forests, estuaries, swamps and open, wet coastal areas, and man-made environments like rice paddy fields where it is the only amphibian that can adapt to different salinities (Ren et al., 2009; Nadia et al., 2020; IUCN SSC Amphibian Specialist Group et al., 2022).
The Crab-eating frog measures approximately 51–70 mm in males and 53–82 mm in females. It is a medium- to large-sized frog with a narrow head and oval snouts. There is a dark stripe on the head between the eyes, and the tympanum (an external hearing structure, the circular patch of skin directly behind its eye) is visible. The underside of the head varies from pure white to white with dark speckles (Gillespie et al., 2021; Ecology Asia, 2024). The sides and back of the body have glandular warts and discontinuous skin ridges. This frog is generally dark brown to grey on the back and legs. It has several markings on the upper legs and has long and pointed fingertips. The fingers on the hind legs have extensive webbing and adhesive discs, but the fingers on the front feet have none.
Fejervarya cancrivora is classified as least concern (LC) by the International Union for Conservation of Nature (IUCN) due to its wide distribution, tolerance to habitat modification and presumed large population. However, the population is decreasing because of over-harvesting for commercial trade for food, deforestation and habitat conversion to agriculture (IUCN SSC Amphibian Specialist Group et al., 2022).
As reported by Evong and Thompson (2001) and Ibrahim (2004), Fejervarya cancrivora is in high demand by local restaurants in Malaysia, where Chinese townspeople consume it for its sweet, tender and tasty meat. The demand for frogs from overseas has been increasing but meeting this demand was hard owing to limited supplies, particularly during the dry season. Thus, over-harvesting is a potential threat to this species (Kusrini & Alford, 2006; Altherr et al., 2011; Grano, 2020). Therefore, more research and surveys are needed to fully understand this species, especially its distribution and its population size, status and trends (IUCN SSC Amphibian Specialist Group et al., 2022).
