Leptodactylid Frogs: Leptodactylidae

With more than 1,100 species of leptodactylid frogs, this is a huge family that has many different-looking species. The smallest species grow only to 0.4 inches (1 centimeter) long from the tip of the snout to the back of the rump, while female helmeted water toads can reach as much as 12.8 inches (32 centimeters) long. Many species in this family have toadlike features, including short legs and warty backs, while others have the look of a typical frog with long, jumping hind legs and smooth skin on their backs. Some have chunky bodies, some are slender, and a few are quite flat. Some of the more unusual members of this family have very baggy skin that hangs in folds from their sides and the upper part of each hind leg, and others have fleshy points, or "horns," on the eyelids.

Although they may look different on the outside, they do share some common features. For example, most of the leptodactylid frogs have teeth on the upper jaw, as well as horizontal pupils in their eyes. A few have vertical pupils. The bones at the tips of the toes of all species in this family either are T-shaped or have knobs. In some species, small pads cover the tips and help the frog to climb up slippery rocks or tall trees. Most species in this family are gray, green, or brown and blend into the background.

A few, however, have bright patterns. The gold-striped frog, for instance, is black with bright yellow stripes. Scientists think that these bright colors trick predators into thinking the gold-striped frog is actually a species of poison dart frog that is also black with yellow stripes. Predators will not eat the poison dart frog, because it oozes a poison from its skin, and may also avoid the look-alike species, even though it is harmless. In addition to its copycat color, the gold-striped frog has red "flash colors" at the tops of its legs. When threatened, this frog and some other species in the family that have similar bright patches move their legs so these spots show. This sudden burst of color may surprise a predator and give the frog time to escape. The gray four-eyed frog has another feature on its back that can scare off attackers. When threatened, it rounds its lower back to show off two large, dark-colored glands. This display gives the impression that a larger animal with two big eyes has suddenly appeared.

Males and females usually look alike. In some species, however, the males develop spines on the front toes and/or chest during the breeding season. These spines help the male ride piggyback and hold onto the female during mating. The males of many species in this family grab the female around her front legs, but some hold her near her back legs while she lays her eggs.