Care Sheet: Mossy Frogs

By Richard Fife of Riparian Farms

The Mossy Frog has only recently become available in the pet trade. The care and breeding of this interesting frog is becoming more refined as our experience with them increases. Most breeders, in the USA have been working with this species for less than 3 years so we still have a lot to learn.

The Mossy Frog, Theloderma corticale, lives in karst zones of northern Vietnam. They make their home in flooded caves and deep niches in the banks of mountain streams. Their range includes the provinces of Vinh Phu, Back Tahi, Cao Bang, and Lang Son. They can be found from 700-1500 m elevation. Their range is decreasing due to habitat destruction and some biologists consider their status as threatened or endangered.

The color and texture of their skin looks like a bunch of moss. Their skin is colored in various shades of green with black and purple spots and stains. They are covered with numerous tubercles and spines thus providing them with a perfect camouflage.

They are mostly nocturnal, however, I have heard them calling during the day. Males have quite a repertoire of calls. Males can be identified by pronounced breeding calluses on the base of their inside finger. There doesn't seem to be much difference in size between males and females. Adults are 7 to 8 cm (3-inches), that can be attended within 6 to 9 months of metamorphism. These frogs will fold into a ball when frightened and play dead.

They actively feed, at night on large insects such as crickets and cockroaches. This is a semi-aquatic species spending much of the time hiding in the water under rocks and floating plants. They will also attach themselves to the crevice on a rock, just above the water appearing to be moss. Their eggs are deposited above the water to protect them from aquatic predators. The eggs hatch in 7 to 14 days with the newly hatched tadpoles dropping from their egg into the water directly below them. Metamorphous from tadpole to frog takes about 3 months.

I recommend that Mossy Frogs be maintained in a covered aquarium (these are tree frogs that have adhesive toe pads and can jump). A ten to twenty gallon aquarium can house two or three frogs. The aquarium should be 1/3 to 1/2 full of water with an aquarium filter. De-chlorinated water that has been conditioned by adding Indian Almond (Terminala cattapa) leaves or a similar commercial aquarium additive should be used. The aquarium can be decorated with broken pieces of clay pots protruding above the water, rocks, and other aquarium decorations. Overhanging rocks or pots are necessary if you intend to breed your frogs. I also use floating water plants like water lettuce. The feeder insects can climb on the water plants until the frogs find and eat them. I feed my frogs, at night, four or five times a week.

Mossy Frogs have been successfully maintained at daytime temperatures of 26- 30 degrees C (79- 86 degrees F) and 22 - 24 degrees C (72 - 75 degrees F) at night. I maintain mine at a constant 78 degrees F both night and day. It is know that local temperatures drop to 4 - 5 degrees C (39 - 41 degrees F) during the winter in their range. A cooling period may or may not be necessary to stimulate breeding and amplexus. I initially cooled my frogs a few degrees in late summer/early fall and breeding commenced shortly thereafter. Clutch size varies from 10 to 40 eggs. Eggs that are deposited in the water fail to develop. Tadpoles can be raised together (they are not cannibalistic) in an aerated aquarium in conditioned water. The tadpoles should be fed daily on Spirulina flakes.

With routine care you will be able to enjoy these unique frogs. They are not difficult to keep and can provide a lot of enjoyment for their owner. Through captive breeding the wild populations no longer need to be harmed by collectors for the pet trade. Have Fun!