Masako fishing frog

Adult males typically measure 63–79 mm (2.5–3.1 in) in snout–vent length; females are larger. Their maximum length is about 100 mm (3.9 in). The tympanum is large and distinct, and the supratympanic fold is present. The finger and toe tips are rounded, but not enlarged. The fingers have only some dermal fringes, whereas the toes are moderately webbed. The dorsum is brown and has dark speckles. A white or off-white vertebral line may be present. The underside is speckled white over a brown background, turning almost entirely white in older individuals (the exception being from the throat). Both sexes have conspicuous yellow-brown femoral glands close to the knee.

A. masako occurs in swamps or along small streams in lowland forests, gallery forests, and degraded secondary habitats (farm bush) in the forest zone. Breeding takes places in standing water - pools, swamps, and marshes. It is nocturnal, burrowing in mud when inactive. Somewhat unusually for an amphibian, its diet consists of fish (e.g., Epiplatys), arthropods, and other amphibians, including younger conspecifics.