Phyllobates bicolor color patterning is very striking. The dorsum and sides are a uniform golden yellow or orange, as well as the dorsal surfaces of the upper arm and thigh (Myers et al. 1978). In contrast, the dorsal surfaces of the forearm and calf are black, and may or may not have dense yellow (or sometimes blue) spotting (Myers et al. 1978). The ventrum may be completely black, or washed with light orange, light gold, or bluish green (Myers et al. 1978). There is occasionally a black patch on the throat (Silverstone 1976). The tympanum is partly yellow-orange and partly black (Silverstone 1976). In some individuals, the tip of the snout is black (Silverstone 1976). Irises are black or reddish-brown (Silverstone 1976).

This species, like P. terribilis, exhibits an ontogenetic color change; juveniles are dark brown to black in color, with two yellowish dorsolateral bands. As the frogs reach maturity, the dorsolateral stripes disappear, and the frogs become more brightly colored. In contrast, the juvenile pattern of light stripes on a dark background is retained into adulthood in other members of the P. bicolor group, P. aurotaenia, P. lugubris and P. vittatus (Myers et al. 1978; Silverstone 1976).

Phyllobates bicolor closely resembles P. terribilis, but P. bicolor is smaller in size and has legs and venter of a different hue than the body color (Myers et al. 1978).
 

As is true of other species in the genus Phyllobates, this species produces batrachotoxins. However, captive-born and bred dendrobatid frogs lack toxicity, since the toxins are acquired at least in part from dietary sources such as ants, mites or beetles (Daly et al. 1980; Daly et al. 1992; Dumbacher et al. 2004). In contrast, the toxins persist in wild-caught animals even when they are maintained in captivity (Daly et al. 1978).

Myers et al. (1978) have speculated that there might be either hybridization or a cline between P. bicolor and P. aurotaenia in the upper San Juan drainage, due to the intermediate size and coloration of the Phyllobates found there.

Phyllobates bicolor inhabits the tropical rain forests of Central and South America. The Choco Indians report finding them most commonly in the Pacific River area of Western Colombia (National Aquarium in Baltimore, 1987).

Biogeographic Regions: neotropical (Native )

Phyllobates bicolor is typically golden-yellow in color and has black flecks on its hind legs. However, the color pattern varies widely. All of the poison-dart frogs have very bright aposematic coloration. This is used as a defense mechanism to warm potential predators of there extreme toxicity. These skin toxins are produced by special poison glands which are scattered all over the animal's body (National Aquarium in Baltimore, 1987). Phyllobates bicolor has terminal discs on its digits that allow them to climb well in shrubs and up mossy tree trunks (Mattison, 1987). Unlike males of most frog species, which are smaller than the females, male poison-dart frogs are relatively the same size when compared to the females (Badger et al, 1995).

• Terrestrial
• Freshwater

Phyllobates bicolor are inhabitants of the tropical rain forests. They live colonially on the forest floor, often near small streams. They do well in the moist, humid conditions that the rainforests provide. The temperature rarely falls below 80 degrees Fahrenheit and the minimal annual rainfall is about 80 inches. Some areas may recieve as much as 400 inches of rain per year. This constant warmth and rainfall keep the habitat of Phyllobates bicolor green all year long (National Aquarium of Baltimore, 1987).

Terrestrial Biomes: rainforest

Phyllobates bicolor is primarily carnivorous. Adults feed on ants, termites, tiny beetles, and other small leaf litter arthropods. They capture their prey using their long, sticky retractable tongue. The young tadpoles may eat each other if placed together in a small area, but mostly they feed on insect larvae, detritis, and on unfertilized eggs left by a visiting female (National Aquarium in Baltimore, 1987).

Most populations of Phyllobates bicolor breed continuously througout the rainy season, some every other month or even more frequently. In order to attract a female, the male will sit on a leaf and call by trilling or buzzing. This may go on for several days. Once a female is attracted, the mating pair must find a suitable location to lay their eggs. In some species, the male will select a location for the eggs prior to obtaining a mate. They are usually laid in a moist place, such as, in the leaf litter, under rocks, or even on certain rain forest plants (National Aquarium in Baltimore, 1987). Phyllobates bicolor have external fertilization with the male fertilizing the eggs as the female deposits them. During amplexus, the male has to clasp his mate under her chin instead of around her waist due to the similarities in size between the males and females (Badger et al, 1995). The female lays from 4-30 eggs in a jelly-like mass, which keeps them moist. Then, they are usually gaurded by either parent until they are ready to hatch. At this point in their development, water is required. The attending parent will squat in the gelatinous mass and allow the young to wriggle up his/her legs and onto their back. The larvae may remain on the adult's back for a few minutes or for several hours. The young are firmly attached by a mucous secretion which is only broken down by the immersion in water (Mattison, 1987). The parent will take the tadpoles to a suitable body of water where they are able to continue their development. This may consist of a puddle in a tree hole or a water holding plant such as a bromelaid or the leaf axils of palms or aroids. It takes about 3 weeks for the tadpoles to complete metamorphosis. After this time, the young will return back to their natural arboreal or terrestrial habitat (Badger et al, 1995).

The pet trade and the destruction of the tropical rain forests are leading to a decline in the Dendrobatids such as Phyllobates bicolor. When the rain forests disappear, so do the animals that inhabit it (National Aquarium in Baltimore, 1987). One of the most spellbinding exhibits of live poison-dart frogs frogs in the United States is located at the National Aquarium in Baltimore, Maryland. Herpetologists there have had success breeding as many as 20 species, but they have also encountered a potential problem. Poison-dart frogs that are born in captivity do not secrete skin toxins. Scientists aren't sure why, but they speculate that the absence of certain bacteria in the environment or perhaps something missing in their diet may be the reason (Badger et al, 1995). The rain forest exhibit at the National Aquarium exists to make the public aware of the diversity of life found within the rain forests throughout the world. Hopefully, this awareness will create a desire to help protect the habitat of species like Phyllobates bicolor (National Aquarium in Baltimore, 1987).

CITES: appendix ii

IUCN Red List of Threatened Species: near threatened

Like other dendrobatids, Phyllobates bicolor are diurnal and are very active. Little has been published on the reproductive behavior of this species in the wild. Zimmermann (1989) has published sonograms of P. bicolor calls, and reports that in captivity, P. bicolor, males initiate courtship by giving a "long-range" courtship call. The female then follows the male to a covered egg deposition site. Once the female approaches within 8 cm, the male emits a "short-range" courtship croak call, ceasing before the female oviposits. Circling and body-anal touching was observed but not amplexus. In captivity, a single female may lay up to three clutches of 12-20 eggs per month. The male moistens the clutch at irregular intervals (hydric brooding). Tadpoles hatch in about 14 days, after which the male transports them to a water-filled brooding site (Zimmermann 1989).

Native peoples in Colombia collect brightly colored frogs and use their poisonous skin secretions to coat the ends of hunting arrows. This method, first reported by British naval captain, Charles Stuart Cochrane, is highly effective in hunting jaguars, monkeys, birds, and small game animals. These skin toxins are of great interest to medical researchers because of their remarkable potency. The batrachotoxins secreted by Phyllobates bicolor are especially valuable for medical science and the study of anesthetics, muscle relaxants, cardiac stimulants, and the control of rapid or irregular heartbeats (Badger et al, 1995).

Scientists believe that the skin toxins of Phyllobates bicolor are so toxic that .0000004 ounces may be enough to kill a human being. Toxins from these frogs work quickly, attacking the nerves and muscles. Nerve cells can no longer transmit impulses and muscle cells remain in an activated, contracted state. The result is death by respiratory or muscular paralysis (Badger et al, 1995).