Asian Toadfrogs: Megophryidae

Most of the Asian toadfrogs have vertical, cat-like pupils, paddle-shaped tongues, and colors and patterns on their heads and backs that blend in with their environment. Some species have warty skin, but others have smooth skin. A few do not have the cat-eye pupils. These include species like the Asian mountain toad, which has a diamond-shaped pupil. The males and females look quite similar for most of the year. In the breeding season, the males of some species develop bright red-, yellow-, or orange-colored spots on their sides and upper legs or some colorful tints on their front toes or on their vocal sacs. The vocal sac is a balloon-like area under the chin that blows up and deflates when the male performs its call. Also during the mating season, the males of some species, including those known as alpine toads and cat-eyed frogs, develop rough patches on the chest and front toes. Male moustache toads are unusual in that they grow spiny "moustaches" when they are ready to mate.

Asian toadfrogs are split into two main groups. One group includes the leaf litter and dwarf litter frogs, the slender mud frogs, the lazy toads, and the moustache toads. All of these frogs have a bump that runs from the second toe onto the first, or big, toe. They usually have large or small "horns" on their eyebrow ridges. The horns are actually pieces of flesh that are pointed. In fact, the name of the family, Megophryidae, is from two Greek words that mean "large eyebrow." Some, like the Asian horned frog, have large, pointed eyebrows. The "horns" on other species are much smaller, and some do not have them at all. This group of frogs has tadpoles with mouths that are pointed upward on their heads and look like funnels. The tadpoles also have a small, fingernail-like beak on the lower jaw.

The other main group of Asian toadfrogs include a variety of mostly large-eyed frogs that have a large bump at the bottom of the second front toe but not on the first toe. Species in this family are the horned frogs, broad-headed frogs, Asian mountain toads, Burmese spadefoot toads, and others. Their tadpoles have larger beaks on both the upper and lower jaws, and mouths that open on the bottom of the head.

The species in this family come in many sizes, too. The smallest only grow to 0.7 inches (1.8 centimeters) long from snout to rump, but the largest top 5.5 inches (14 centimeters) in length. The broad-headed toads can grow to 6.6 inches (16.8 centimeters) long. The females usually outgrow the males, but in the moustache toads, the males are slightly longer.