That Reptile Blog – Reptile, Amphibian and Exotic Pet Care and Information
The wonderfully bizarre Malayan Leaf Frog, Megophrys nasuta, has always been a somewhat difficult species to keep. However, we now have a better understanding of its needs, and captive breeding is becoming more regular. As it turns out, the Malayan Leaf Frog’s reproductive behavior is as unusual as its appearance.
Natural History
Malayan Leaf Frogs range from southern Thailand through the Malayan Peninsula, Indonesia and Sumatra to Borneo. Despite the large range, uncanny camouflage and a preference for forested habitats renders them difficult to find. Little is known of their status and conservation needs.
Malayan Leaf Frogs are classified in the family Megophryidae, a group of 150+ largely nocturnal, leaf-mimicking species. Most prefer walking to hopping, and many are largely unstudied.
Early Problems: Supply and Care
A shortage of males was the main impediment to breeding this frog when it first began showing up in the USA. Even working through my Bronx Zoo connections, it was well over a year before I could find a male in the mid 1980’s. It seemed that collectors did not bother with the thin, 3 ½ inch-long males since the stout, russet-colored females, which reached 6 ½ inches in length, brought a much higher price.
Also, Malayan Leaf Frogs are difficult to transport…many new arrivals bore snout injuries, which often led to fatal infections.
Basic husbandry was and remains a problem for some keepers. Despite their tropical origins, these forest specialists fare best at temperatures of 66-70 F; most were kept warmer and did not thrive. They do not last long on a diet comprised of 2-3 insect species; roaches, silkworms, sowbugs, earthworms and wild-caught invertebrates are essential to their long-term health (please see article below).
Courtship
Males begin calling sporadically throughout the year, it seems. Their odd voices sound like a person “clucking” their tongue (please see video below).
A rain chamber might be useful in stimulating bringing these frogs into breeding condition, but it seems not absolutely necessary. A 4-inch-deep, well-filtered pool should be available at all times, in case breeding should commence.
Amplexus
In common with African Clawed Frogs, Surinam Toads and other “primitive species”, male Malayan Leaf Frogs grasp females just above the rear legs when entering the mating embrace. This position is known as Inguinal Amplexus. Most other frogs utilize Axillary Amplexus, wherein the female is grasped just behind the front legs.
Egg Deposition Sites for Cave-Breeders
Curved pieces of cork bark should be positioned over the water area in the terrarium. Malayan Leaf Frogs are unique in that females attach their eggs to the ceilings of natural caves and other such shelters (you can try artificial caves as well, but cork bark offers, I believe, the best attachment site).
The jelly surrounding each clump of eggs is extremely thin, so take care not to jostle the caves when you check them.
The eggs hatch in 10-12 days, at which time the tadpoles slide down strands of jelly (which may reach 6 inches in length) to the water.
Rearing the Tadpoles
The 1/2-inch-long tadpoles should be transferred to a filtered aquarium that has been set up before hand; undergravel, sponge or corner filters are preferable, as the delicate frogs-to-be cannot tolerate swift currents. Water temperatures should be slightly higher than is acceptable for adults; 75-77 F works well.
The tadpoles will remain motionless for 2 days after hatching. Malayan Leaf Frog tadpoles have huge, funnel-shaped mouths and are, like African Clawed Frog tadpoles, filter feeders. However, these unique mouthparts do not develop until 6-8 days after hatching; prior to that, the tadpoles do not feed. This is an unusually long fasting period for a tadpole… and is a very frustrating period for keepers!
Once equipped to eat, the tadpoles will swim about sucking in finely-crushed tropical fish food flakes and fry foods. Provide live plants and floating cork bark, as resting tadpoles tend to group up near such shelters.
Metamorphosis
Rear legs appear by day 70-80, at which time the tadpoles are nearing 2 inches in length. The mouthparts then begin to regress, and the tadpoles cease feeding and remain motionless on the tank bottom. The front legs sprout within a few days.
At this point, reduce the water level to 1 ½ inches, and provide easy access to land; platforms, gravel islands or tilting the aquarium (to provide a sloped land area) all work well. The emerging froglets are barely 1/2 inch long, and must be kept cool and moist, and should be provided with access to a shallow water source and plenty of cover. Newly-transformed Malayan Leaf Frogs will choose leaf-letter or growing plants over caves as shelters. Live pothos plants root in gravel and serve well as hideaways.
The classic “horns” above the eyes do not appear until the frogs are at least 1 month of age. Age at sexual maturity has not been definitively established, but reportedly may occur as quickly as age 11 months in captivity.
Feeding Young Frogs (Metamorphs)
While pinhead crickets are the simplest diet to provide, relying solely upon crickets, even if they are powdered with a vitamin/mineral supplement, and will lead to a very poor survival rate. Best to set up breeding colonies of fruit flies, flightless house flies (for use as the frogs grow), earthworms, flour beetles, springtails and sow bugs well ahead of time, so that a supply of newly-hatched invertebrates of several species is assured.
Aphids (please see photo), tiny moths, leaf litter invertebrates and wild-collected “meadow plankton” will ensure your success in raising these captivating but delicate little fellows (please see article below).
Further Reading
Video: Malayan Leaf Frog calling (great!)
Malayan Leaf Frog Natural History
Horned Frog image referenced from wikipedia and originally posted by Olaf Leillinger
Aphids image referenced from wikipedia and originally posted by Michel Vuijlsteke
Aphids image referenced from wikipedia and originally posted by Michel Vuijlsteke
Frank thanks a lot for this article. nasutas are probably one of the most bizarre family of frogs.. i am in the look out for a pair or 2 if i manage to find some.. i seem to find only wc animals i would like cb animals but not many people has nay success breeding them
Hello Mike, Frank Indiviglio here.
Thanks for the kind words. WC females still predominate, especially in stores. Specialist private breeders are the best source of CB animals, but young are often spoken for ahead of time,
Best regards, Frank Indiviglio.
Hi Frank, thanks for the information. I just wondered what other species you can keep with them ? I have recently purchased two cb and would like to add other species to the tank but. Was unsure what could be added. Thanks
Thanks for your interest and the kind words. Nice you were able to find CB frogs. They are still viewed as a somewhat sensitive species; I would advise keeping them alone.
When mixing species, there is a real danger that micro-organisms/parasites which do little harm to one can be fatal when transferred to a related species. Similar to the concept of tourists becoming ill after drinking tap water in foreign countries, or the tragedies that occurred when certain common illnesses were transferred from Europeans to Native American many years ago. In zoos, we test animals very carefully before mixing, and avoid doing so in many cases, as would be true for Malayan leaf frogs.
Also, feeding competition/stress and other factors can be very difficult to access, especially with nocturnal animals.
I’ve set up many mixed species exhibits with other amphibians…please let me know if you have any others in mind, and I’ll be glad to help. Please update me on how your frogs work out as well…still much to learn about them.
Good luck, enjoy and please keep me posted.
Best regards, Frank Indiviglio.
Hi Frank,
Thank you for your information – it was certainly helpful. Do you have any idea what could be the cause of illness in the tadpoles- what sickness could they be prone to?
In addition, how often should the tadpoles be fed?
I am currently rearing three tadpoles at a water temperature of 22°C, and after 2.5 months the largest of these is only 3 cm big, with no hind legs in sight. I’m feeding them a ground mixture of algae wafers and fish food.
Hello,
Thanks for the kind words, much appreciated.
It’s difficult to gauge how much food filter-feeders need; as they tend to be feeding whenever active. Best to have food available as often as possible, as long as you can maintain water quality as well. You’re doing quite well, as losses often occur early, soon after they hatch. Rear legs can appear at age 2-3 months, but this varies with diet type, water quality, temperature. They are usually a bit larger than you describe by age 2.5 months, but this is not a great concern; you can try feeding more, but poor water quality will kill them faster than a reduced diet. You might try very slowly raising the temperature to 24-25 C; some zoos have used 26 C as well, but make any changes very slowly.
Medicating tadpoles is extremely difficult, as we know little about their diseases and treatments. I’ve had good results with methylene blue (other species); standard fish medications can be used in some cases, but recommended dosages are usually too strong for tadpoles, which absorb meds over a greater surface area than do fishes. Please keep me posted, enjoy and let me know if you need more info, best, Frank
Dear Frank,
Unfortunately, my raising the temperature to 24 C resulted in death for all 3 tadpoles – death occurred in a very short space of time, in 25 minutes. The increase in temperature may not have been gradual enough.
Thank you for your time and reply though, it is much appreciated.
Hi,
Sorry to hear…yes, tadpoles sometimes adjust to quick changes but ideally changes should take place over several days. You had done so well with them, which is not common, so, unfortunately, I did not think to mention that; I apologize, i should have been more specific. best, Frank