SUMMARY
PREVALENCE: Rare
ACTIVE PERIOD: Active at night
KEY ID FEATURES: Bulbous eyes protruding from top of head, highly webbed hind feet
SIZE: ~3cm
IUCN: LC - Least Concern
GALLERY
IMPORTANT: Many frogs have significant variance in coloration and pattern even within the same species. There can also be extreme differences in appearance from juveniles to adults and some species appear very similar in maturity.
DESCRIPTION
The floating frog that can currently be found in Hong Kong is an introduced population from South East Asia. The original floating frog population in Hong Kong became locally extinct as a result of habitat loss.
The floating frog has distinct morphology with a truncated body, short, minimally mobile forelimbs, compact fully webbed feet on the hindlimbs, and protuberant eyes positioned on top of the head allowing the frog to see out of the water while the majority of the head and body remain submerged. They can be dark brown, light brown, or nearly black with yellow undertones, and can also have thin broad green or light brown vertebral stripes. The body is covered in granules with tubercles visible on the lower flanks. The head is more narrow than the body and the snout is short and nearly completely rounded. Dark blotches and irregular striping can be seen on the body. The forelimbs have dark lines down from the shoulder transitioning to flecks and spots. Hindlimbs have dark blotches.
The venter is light in color, often white or light yellow on the chin and belly. There are densely clustered white tubercles under the chin that become more sparsely arranged on the belly. The same white tubercles form a distinct line on either side of the belly running in a curve and terminating on either side of the cloaca. Dark stripes can be found under the forelimbs and hindlimbs. Addition black blotches can been seen on the venter between the cloaca and the joint of the hindlimb and body.
Floating frogs have four digits on the forelimbs, absent webbing with the second digit being proportionally shorter. Digits on the hindlimbs are completely webbed.
HABITAT
The floating frog that can now be found in several restricted locations appears well established and, despite the highly localized populations on Lantau, can be found with relative ease where they occur. They are found in muddy wetland habitat with standing water. They can be found at night floating in small pools and puddles and quickly dive down to bury in mud and grass when disturbed.
MISTAKEN IDENTITY
The rough-skinned floating frog is a very distinct species with unique morphology and a highly restricted distribution. As a result it is not easily confused with any other species in Hong Kong. The most distinguishing features are the bulbous eyes positioned on top of the head and the truncated body, along with the unique arrangement of tubercles on the venter and extensive webbing on hindlimb feet.