Three-Toed Toadlets: Brachycephalidae

Physical characteristics: Reaching just 0.5 to 0.8 inches (1.25 to 2 centimeters) long, the pumpkin toadlet is one of the smallest frogs on the planet. Its name comes from its bright orange color, its warty skin, and its tiny size. Sometimes the frog's color is yellow rather than orange, and people call it a gold frog instead. Its head has a short, rounded snout and two large, black eyes. Beneath the skin of its back, this toadlet has a bony plate or shield that is attached to the backbone. The bony plate led to the third common name of this species, Spix's saddleback toad. Its front legs are thin and end in two, stubby Reaching just 0.5 to 0.8 inches (1.25 to 2 centimeters) long, the pumpkin toadlet is one of the smallest frogs on the planet. Its name comes from its bright orange color, its warty skin, and its tiny size. Sometimes the frog's color is yellow rather than orange, and people call it a gold frog instead. (Photograph by B. Kevin Schafer/Corbis.) toes. The slender hind legs, which are longer than the front pair, end in three stubby toes. The other toes on their feet are either just nubs or missing altogether. The bones inside the toes are each shaped like a "T" at the tip.

Geographic range: Pumpkin toadlets live in southeastern Brazil along the Atlantic coast.

Habitat: These frogs live and breed in humid, warm forests along the ocean. They spend most of their time in piles of dead leaves that cover the ground.

Diet: Pumpkin toadlets scrounge around in the leaf piles for small arthropods, including mites and tiny insects called springtails. Studies of pumpkin toadlets show that the frogs get more than half of their diet from springtails.

Behavior and reproduction: Pumpkin toadlets, which are active during the daytime in the rainy season, are not difficult to spot. Their bright orange or yellow color is very noticeable as these tiny frogs slowly walk over leaves. If the day is very humid, they may climb onto low branches of bushes and trees. In a rather unusual behavior, this frog swipes its front and back legs over its head on down its body. The frog performs this leg-waving movement when cleaning its body of dirt. A male frog also will wave its front legs in front of its eyes when another male comes close. This sometimes scares off the newcomer. If it does not work, the male will protect his territory by wrestling with and shoving the other male until he leaves.

Each male calls from his own territory during the rainy season. He holds his body up high, draws in air to fill up his vocal sac, and performs his call, which is a repeated buzzing sound. When a female approaches, he wraps his front legs around her waist and then walks with her in this position as she shuffles around looking for a good spot to lay her eggs. Once she finds a site under a log or in a pile of leaves, the male scoots up to grab onto her near her front legs. For the next 30 minutes or so, she lays her eggs. Females usually lay five, large, yellowish white eggs at a time. After the female lays the eggs, the male leaves, but the female stays behind for a few moments to roll the eggs along the ground with her hind feet. Now covered with dirt, the eggs are well-hidden from the view of predators. The eggs hatch 64 days later, skipping the tadpole stage, and small, reddish brown toadlets crawl out. The newborn toadlets have a tiny tail, but this disappears soon.

Pumpkin toadlets and people: Scientists are studying the medical uses of the very strong poisons, or toxins, that ooze from this frog's skin. The toxins affect the heart and other muscles and the nerves.

Conservation status: The IUCN does not consider this frog to be at risk. Although it lives in a fairly small area, the pumpkin toadlet is quite common there. In addition, part of its habitat falls within various protected areas. ∎