The Emerald green tree frog is an endemic species of tree frogs in Taiwan. They are distributed primarily along the Nanshi and Beishi river basins and low elevation areas such as Xindian’s Guangxin, Wulai’s Wa-Wa valley (renamed Neidong), Yi-lan’s Fushan Botanical garden and Jiaoshi, spreading across Yi-Lan and Taoyuan counties respectively. Their mating calls can be heard all year round, with breeding peaks from March to May and again from September to October.
Comparisons with related species: The Orange-belly green tree frog has ventral orange coloring but without black spots; the Moltrechtis green tree frog does not have white stripes on the lateral side of the body, and has orange irises.
Adult characteristics:This species is the largest green tree frog in Taiwan. Males and females vary greatly in size, with male body lengths reaching 5 to 6 centimeters, and female’s 6 to 8 centimeters. Their dorsal surface is green or yellowish-green, the skin texture coarse and covered in granules, and no mid-dorsal stripes and dorsolateral folds. The ventral surface is white and some have black spots or small granules. They have circular tympanums, yellowish-golden skin folds behind the eyes, black pupils and golden irises.
A white stripe extends from the snout to the flank, with black spots beneath the stripe. The toes are green, with well-developed sucker pads, the thigh flaps inconspicuous, and the digits fully-webbed. During rest, the front-hind limbs and the outer edges of the posterior end are white or golden yellow-colored. Males have outer vocal sacs and small granulated nuptial pads on their first and second digits.
Tadpole characteristics: Body lengths range from 12.8 to 15.2 millimeters (stage 31-38) and are oval-shaped. The snout is bluntly tipped and the mouth is located at the snout end. The eyes are located on the dorsal side, with a blow hole on the lower lateral side of the body. The dorsum is colored brown, dark brown or dark green, the ventral side is lightly pigmented, and the tail is unevenly colored in dark brown. The tail is lanceolate-shaped with a narrow circular tip.
Egg characteristics: The eggs are white and bundled in a pinkish foam mass, often grouped in several large clumps. The egg mass turns yellowish after drying in the air.
Habits and habitats
This species is often found around hills, orchards, tea plantations, bamboo groves or low shrubs. The males call to females by emitting a low “guah” sound while among aquatic plants, and mating and spawning are completed in trees. The eggs are laid in shrubs, tree holes in tea plantations, or on the walls of man-made water vessels, and the tadpoles develop within them. Adult frogs like to prey on flies.
National Museum of Natural Science