THE KOKOE FROG
Phyllobates aurotaenia

Chris Miller

Introduction & Natural History
Although Phyllobates aurotaenia (Silverstone 1976) is one of the newest species in the dart frog hobby, it is also one of the most over looked species. With its bold behaviour and canary like trill, this species deserves a closer look by enthusiasts. All stock in the hobby can be traced back to a couple of shady German importations during the mid-nineties, and several years later, captive stock made it to the U.S.

P. aurotaenia was first described by Silverstone in 1976 and placed in a group with P. bicolor, being one of the three (only two known at the time) species used to poison darts. It comes from the Colombian Chocó, west of the Andes, and bordered by Río Atrato on the northeast: and Río San Juan on the southwest. It is mainly a lowland species with the upper reaches of range at about 500m (1700 ft) above sea level. P. aurotaenia has at least four colour forms in the wild, three of which are present in the hobby today, all of which have a base colour of black with blue to white marbling on the bellies, and metallic blue to green spotting on the legs. The forms in captivity are:

Highland with wide coppery gold metallic dorso-lateral stripes, which may fuse and completely cover the back of the frog.

Lowland with narrow yellow to gold stripes, like those of P. lugubris. On some of the larger females and older males, flecking may develop down the back of the frog in between the stripes, but not enough to make the frog easily confused with the highland form.

Green, with wide metallic green stripes and some moderate green flecking down the back of mature animals.

While the highland and lowland forms share the same call, an irregular bird-like trill, much like a lower, slower version of a P. vittatus call, the green form is markedly different. Its call is a much more even trill, a bit higher in pitch than the other two that sometimes sounds like an even, melodic chirping. This fact has led some of us to wonder whether the green form is its own species, along with the other known form, a red striped frog.

The red form looks and sounds exactly like the green form with red stripes and flecking. As far as I know, this frog is know from only a few specimens in the wild and a pair of males in captivity. Unfortunately we will not be sure what the true story is until Colombia becomes a more hospitable place to conduct research.

One other interesting point about P. aurotaenia's call is that they do not make a "chase" call like P. terribilis and P. bicolor, both of which will buzz when they have a female following them during courtship, a call which differs from the trill they produce when they defend their territory.

Aside from the males' call, the only other way to sex P. aurotaenia is by size and body type. Males grow to about 25mm and have a slender build; females grow to about 30mm and have a chunkier shape. The highland form seems to be the largest, followed by the lowland, with the green being the smallest, though this seems to vary from collection to collection.

Captive Care
Phyllobates aurotaenia is as undemanding as dart-poison frogs go. Their small size enables a trio to be maintained a 10-gallon terrarium. All my frogs are in the finished part of the basement where the temperature ranges between 20 and 23˚C all year rounD. The setups are simple, with a layer of gravel topped off by 3 inches of orchid grade extra long fibre Sphagnum moss purchased at the local orchid greenhouse. I prefer this to other soil mixes, as it will stand up to wet conditions for longer periods of time. A spent fruit fly culture vial with its bottom cut out is used as a siphon access to drain off extra water. I use the little plastic cap that comes with the vials to keep curious frogs out of the tube. The moss is then topped with ordinary leaf litter from outside, and a fresh layer is just laid down over the old whenever needed. Philodendron and Selaginella kraussiana are the main plants, with several accidental Phragmipedium besseae seedlings and some random Pleurothallis round out the greenery. A T-Rex corner water dish with suction cups is suspended in every tank for soaking. I put a honeymoon hut underneath the dish, as the males like the overhead security, and will call from the top of the hut with more gusto. Film canisters lying horizontally are scattered about the tank as alternative sites and are used on occasion.

Like all other Phyllobates they relish large prey items, and, while they will devour fruit flies by the hundreds. They seem to breed better after a meal of medium crickets. These frogs will also eat small waxworm, small earthworms, and small tropical cockroaches. Frogs will actually fight over the wriggling end of a wax worm sticking out of a cage mate's mouth. Food is dusted with MinerAll and Herptivite every other week (similar to Nutrobal)

Breeding
Not only are they easy to keep, but also they are easy to breed as long as certain conditions are met. As previously stated, I keep my breeders in trios, two males and one female. This ratio is more productive as females are almost always willing to breed, where the males may not be. However, when an extra male is added to the pair, they keep each other at peak condition, and clutches are produced regularly. Two things are needed to stimulate a properly sexed pair to breed. Firstly, they need to be well fed; they produce larger clutches with larger eggs, and have a higher hatch rate at a borderline obesity.

Secondly, the enclosure needs to be sopping wet. The wetter the better, they like the water level even with the land, and some pockets of open standing water in the low areas are appreciated. This poses quite a problem in the planted vivarium, allowing the water level be kept high, without the plants rotting, keeping the standing water fresh and the leaf litter from turning into slime. The way I solved these problems is by creating a cycle that lasts 2 weeks. Starting with a low waterline, the enclosure is misted twice a day for 5 days, with exact time not being important. A heavy feeding period begins with larger food items offered every other day. By day 6, the frogs are fat and the water level is high, so feeding and spraying stops, for days 6, 7, and 8. It is usually during the transition period, that the frogs will lay their eggs. For the remainder of the second week, the frogs are fed fruit flies every 3 days, and not misted. On day 9 or 10, the water is drained out of the tank, and the cycle is started over again at the end of the week. It took just I month or 2 cycles for the frogs to catch on.

When they do lay eggs, the clutch size varies from as few as 6 to as many as 35. More seasoned breeders will lay their eggs on the Petri dish 99% of the time, with the extra going to film canisters. Unfortunately the younger frogs leave their eggs around the enclosure randomly, and can produce many hundreds of eggs before getting a fertile clutch.

Eggs are pulled out nightly, and moved to the cooler part of the basement and kept at 65°F. The eggs are not light sensitive and are kept on an orchid bench. They are irrigated with water and a few drops of mould inhibitor until they hatch, usually 14 to 21 days after fertilisation. After the tadpoles hatch they are transferred to a plastic shoebox filled with softened well water. I generally put 5 tadpoles in a shoebox along with a clump of hornwort for food and shelter. They are offered Sera Micron on their third day in the water, enough food is put in the water to turn it light green when mixed in. The food settles out in a day, and the tadpoles are fed again when the bottom of the box is no longer green. Water is changed every other week, the box is rinsed out and the sides and bottom are wiped clean. The tadpoles take about 55 to 65 days to start metamorphosing. When the front legs pop through, the tadpole is moved to a half land half water box in the frog room to complete the metamorphosis.

Rearing Froglets
Despite their small size the froglets can feed on large prey items. The young are not the best- hunters, and do not thrive on D. melanogaster. The froglets do not seem to chase down food that runs away, so they are better suited to take D. hydei even right out of the water. I like to raise my babies in shoeboxes for several months as this seems to increase their growth rate, as the froglets spend less energy on hunting. The froglets will mature and be ready to reproduce between 10 and 14 months of age.