Amero-Australian Treefrogs: Hylidae

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AMERO-AUSTRALIAN TREEFROGS: Hylidae

PHYSICAL CHARACTERISTICS

The many species of Amero-Australian treefrogs often appear very different from one another. Inside their bodies, however, they have similar skeletons. For example, the set of bones on one side of the chest overlaps with the set on the other side, and the bones at the tips of the toes are shaped like claws. From the outside, most of the treefrogs have slender bodies, long legs, and wide toe pads that may be round or triangular-shaped. A few of them have plump bodies and short legs, and some have no toe pads. Most have webs that reach at least halfway up their rear toes. Webbing on the front toes is present in some species, but not in others.

All of the Amero-Australian treefrogs have teeth on the top of the mouth. Only a few have teeth or teethlike bones on the bottom of the mouth. Most have a round eardrum that shows on each side of the head. Some have smooth, shiny skin, but others are covered with small bumps. A few, like the horned treefrog, have large heads, small spikes above their eyes, and two large points on the top of the head that might be mistaken for ears or horns.

Most of the frogs in this family are green or brown with dark markings. These camouflage colors and patterns help them to blend in with their surroundings. Their undersides are typically light in color, sometimes with light brown, brown, or black marks. Many have bright patches on their sides and/or the insides of the hind legs. The red-eyed treefrog, for example, is a lime green frog with sides that are each colored with a set of large blue areas separated by thin white to yellowish lines. A few treefrogs, such as the Chachi treefrog, are very colorful on their backs, too. This frog is yellow with a detailed pattern of red to reddish brown on its back and head.

Depending on the species, Amero-Australian treefrogs may be as small as 0.8 inches (2 centimeters) from the tip of the snout to the end of the rump or as large as 4.8 inches (2 to 12 centimeters). Males usually look similar to females, but commonly are smaller and may have bright yellow or dark gray vocal sacs. In addition, most males have rough patches and occasionally spines that form on their front legs and/or feet during the breeding season. These patches are called nuptial (NUHP-shul) pads and help the male hold onto the female during mating.

GEOGRAPHIC RANGE

Amero-Australian treefrogs live in much of North, South, and Central America, Europe, eastern and parts of southeastern Asia, Australia, and far northern Africa. They are not found in the northern reaches of North America, where the weather is frigid, nor in extreme southern South America.

HABITAT

Most Amero-Australian treefrogs live in rainforests or in other warm, moist forests. Some rainforests around the Amazon River in South America are home to more than 40 different species from this family. Numerous other species, however, live in cooler areas like the forests of the northern United States and Canada. Some treefrogs prefer drier spots, such as grassy fields and even deserts. The majority of treefrogs live up to their name and live in trees or at least on plants. Some, especially those that live in dry areas, may live on the ground or underground.

DIET

Amero-Australian treefrogs hunt by ambush, which means that they sit still, wait for a creature to wander by, and then quickly nab it and eat it. The majority of the treefrogs eat only arthropods (AR-throe-pawds), which are insects, spiders, and other animals that have no backbones, but have jointed legs. An animal without a backbone is called an invertebrate (in-VER-teh-breht). A few treefrogs are especially picky eaters. The greater hatchet-faced treefrog, for instance, is a small, green frog that usually only eats ants. Some of the treefrogs, such as the Sumaco horned treefrog, have large heads and large mouths and are able to grab and swallow larger animals, including small lizards and frogs.

BEHAVIOR AND REPRODUCTION

Almost all of the treefrogs are active at night and hide during the daytime. Their hiding places may be underneath loose bark on the side of a tree, between two leaves or between a leaf and a stem, in a crack in a rock, or tucked into any number of other tiny openings. A few species, including the northern cricket frog of North America, are active during the day instead. Those that are active at night spend most of the time sitting still on leaves or branches, or on the ground, waiting for a meal to wander past. People usually see them most often during or after a rain when the frogs move around more.

The treefrogs that live in deserts and grassy fields take special steps to keep from drying out. The water-holding frog of Australia lives in very dry parts of Australia. To survive, it spends most of its life underground. Like other burrowing treefrogs, it has shovel-like bumps, called tubercles (TOO-ber-kulz), on its feet to help it dig backward into the ground. Once it is completely buried, it sheds its skin, which hardens into a waterproof coat. The frog remains inside the coat until the rainy season arrives, and then comes out of its burrow to mate and to eat until the dry weather returns. This resting period is called estivation (es-tih-VAY-shun). Some treefrogs in hot places in South America can survive above the ground. They ooze a goop from their skin and smear it on the rest of the body. The goop is waxy and prevents the frog from drying up.

Frogs that live in cold climates, such as the northern United States and Canada, spend the winter in a state of deep sleep. This is called hibernation (high-bur-NAY-shun). Cope's gray treefrog is an example. It crawls into a hiding place under leaves or underground and stays there until spring. During hibernation, much of the frog's body freezes solid, but the frog thaws out safely when the weather starts to warm up.

The typical treefrog avoids many of its predators by staying out of sight during the daytime and by remaining still for most of the night and blending into its surroundings. If a predator spots a treefrog and draws near, most treefrogs are good jumpers and will simply leap away. A few, like the black-eyed leaf frog, can soar many feet (several meters) after leaping from a high branch. Others, such as the northern cricket frog, can hop to the water and continue scooting across the surface for a short distance. Some species of Amero-Australian treefrogs do not try to leap away and instead play dead by tucking their legs against the body and freezing in that position. Often a predator will lose interest and wander away, leaving the frog alive. The Amazonian milk frog and several other treefrogs have another way to avoid predators. These frogs ooze a milky substance from the skin that hurts the eyes and mouth of a predator.

Breeding season for the frogs that live in moist forests, such as cloud forests in the mountains or rainforests, may continue off and on throughout year after almost any heavy rain. These frogs usually mate in streams or ponds that are filled with water all year long. The frogs that live in cooler climates typically breed in the spring and use temporary pools of water that will dry up later in the year. Treefrogs that live in dry areas also use temporary pools, but they breed only when the rainy season arrives, which sometimes does not happen for a year, two years, or more. While many other species of treefrogs will call and mate in large groups, the males of those species that breed on land usually call alone. For example, a male spiny-headed treefrog calls alone from a tree hole or from a bromeliad (broh-MEE-lee-ad), which is a plant that grows on trees and holds little puddles of water between its leaves. When the male pairs with a female, the two also mate away from the other frogs.

TWIN FROGS

Two of the treefrogs that live in the forests of North America are able to change colors from a bright grass green to a brown-and-black, tree bark pattern—or vice versa— in a matter of about an hour. The two frogs, known as the eastern gray treefrog and Cope's gray treefrog, not only have the same color-changing ability, but they also look almost identical. Even frog experts often cannot tell one from the other unless they hear them. The males of both species make a trilling call, but when they are calling at the same time, the call of the male Cope's gray treefrog is noticeably faster.

The males' calls announce the breeding season. The males usually have a single vocal sac, a bit of flesh on the throat area that blows up and deflates when they call. Most call from the ground or on plants or trees. A few species, like the Manaus slender-legged treefrog, have two vocal sacs that inflate upward around the head, and they call while floating in the water. If they had the typical single vocal sac that inflates out and down from the throat, they would bob around in the water. In most species, the male finds a good spot for breeding and makes his calls not only to attract a female but also to announce his territory to other males of his species. If another male tries to move into his territory despite his calls, the two may wrestle with one another, sometimes even resorting to biting. Perhaps the most vicious fighters are the male gladiator frogs, which have sharp spines on the inner toe of each front foot. Two battling males will swipe their spines at each other, often causing bad cuts and sometimes death. Spiny-headed treefrogs may also fight by gashing one another with their head spines.

Once a female approaches a male for mating, he scrambles up and lays flat against her back while hanging on with his front legs wrapped around the top of her back. The females of some treefrogs, including many of the species in North America, lay their eggs in the water, and the eggs hatch into tadpoles. Some treefrogs instead dig a shallow dip or a deeper hole in the ground or find an already-made dip and lay their eggs there. When rain floods the dip or the burrow, the tadpoles hatch and float off to a nearby pool of water. The females of other treefrog species lay their eggs on leaves that hang over the water or make foamy nests for them on plants above the water. A number of treefrog females lay their eggs on the sides of tree holes or on bromeliad leaves above a little puddle of water. These eggs hatch into tadpoles and slide off the leaves, drop out of the nests, or wriggle from the sides of bromeliad leaves and tree holes to fall into the water below. In some species of treefrogs, the eggs spend time inside a pouch on the female's back or simply stuck to her back. Among several of these species, the eggs hatch into tadpoles inside the pouch or on the female's back, and she drops them off at a pond or in a puddle inside a tree hole or bromeliad. The eggs in a few species never become tadpoles at all and hatch right into froglets.

AMERO-AUSTRALIAN TREEFROGS AND PEOPLE

Some local people in tropical areas eat the larger Amero-Australian treefrogs, including the very large tadpoles that are seen in some species. Some treefrogs, however, are not safe to eat. The giant waxy monkey treefrog, for instance, oozes a very powerful poison from its skin that can cause a person to become extremely sick or to die.

Many species of treefrogs can be found in the pet trade. The red-eyed treefrog with its green back, blue-and-white sides, orange toes, and large, red eyes is especially common.

CONSERVATION STATUS

The World Conservation Union (IUCN) lists one species that is Extinct, which means that it is no longer in existence; fifty-three species that are Critically Endangered and facing an extremely high risk of extinction in the wild; seventy-seven species that are Endangered and facing a very high risk of extinction in the wild; fifty-four that are Vulnerable and facing a high risk of extinction in the wild; twenty-seven that are Near Threatened and at risk of becoming threatened with extinction in the future; and 183 that are Data Deficient, which means that scientists do not have enough information to make a judgment about the threat of extinction.

The one Extinct species was from Brazil. Known as the spiny-knee leaf frog, the first—and only—one was seen more than eighty years ago. Scientists have looked for others since then, but have found none. Many of the fifty-three Critically Endangered species in this family have had die-offs because of infection with a fungus, called chytrid (KIT-rid) fungus. This fungus has also killed frogs from many other species in different frog families around the world. Morelet's treefrog, which is found in Central America and Mexico, is one of the species of Amero-Australian treefrogs that has had a loss in numbers because of the fungus. Some individuals have probably also died as their forests have been destroyed. This frog was once quite common, but now it has disappeared from many places. Scientists believe that its population will drop by another 80 percent by the year 2014.

RIOBAMBA MARSUPIAL FROG (Gastrotheca riobambae): SPECIES ACCOUNTS

Physical characteristics: Also known as the Ecuadorian marsupial frog, the Riobamba marsupial frog gets its name from the pouch, or marsupium (mar-SOUP-ee-uhm), on the rear of the female's back. The male has no pouch. The Riobamba marsupial frog is a plump green to brown frog sometimes with darker colored oblong blotches of color on its back. The blotches are outlined in dark brown. Its back is smooth or has a cracked appearance. Its underside is grainy-looking, has a cream color, and is sometimes spotted with gray or brown. The frog has a small head with large, brown eyes and a wide mouth on its rounded snout. All four of its short legs have toes with slightly rounded pads on the tips. Males may be a bit shorter than females. Males usually grow to 1.4 to 2.3 inches (3.4 to 5.7 centimeters) from snout to rump, while females reach 1.4 to 2.7 inches (3.4 to 6.6 centimeters) in length. Until 1972, this frog's scientific name was Gastrotheca marsupiata, but that name is now used by a different species found only in Peru and Bolivia.

Geographic range: It lives in northwestern South America among the Andes mountains in parts of Ecuador.

Habitat: It lives along the ground, making its home in mountain fields, farmlands, and even city gardens.

Diet: It eats beetles, as well as other arthropods.

Behavior and reproduction: The Riobamba marsupial frog hides during the day in small openings in rock piles and stone walls and among plant leaves. At night, it becomes active and looks for food on the ground. The frog is most known for the unusual way it has its young. Mating begins when the male calls with a "wraaack-ack-ack" sound and attracts a female. In most frogs, the male sheds fluid, which contains microscopic cells called sperm, over the female's eggs as she lays them. Only after the sperm mixes with the eggs can they start developing into baby frogs. In the Riobamba marsupial frog, the male sheds the sperm-filled fluid, but spreads it on her back behind her pouch. As she lays her eggs, he pushes them through the fluid and into her pouch. A single female may lay sixty-four to 166 eggs at a time. The eggs hatch inside her pouch seventy to 108 days later. The female moves to shallow water, pulls open the pouch, and the tadpoles swim out. The female uses her hind feet to scoop out any stragglers. The tadpoles change into froglets in four to 12 months.

Riobamba marsupial frogs and people: Scientists are interested in the frog because of the unusual way it reproduces.

Conservation status: The IUCN lists this species as Endangered, which means that it faces a very high risk of extinction in the wild. It was once a common species, but now is rare. Scientists are not sure why its numbers have dropped, but they think that the change in its habitat from forests and meadows to farm fields is likely part of the reason. ∎

SUMACO HORNED TREEFROG (Hemiphractus proboscideus): SPECIES ACCOUNTS

Physical characteristics: The many jagged edges of the Sumaco horned treefrog set it apart from most other frogs. Its head is very large compared to its body. The snout is wide and triangular with a very pointy front. It has other edges on its head that give it the appearance of having pointy "cheeks" and "ears." Its eyes are large and set toward the side, and it has additional small points above its eyes. The Sumaco horned treefrog is several shades of brown, often with noticeable dark streaks on its face and dark bands on its legs. Its body is a bit flattened, and parts of the backbone poke up enough that they are visible as bumps down the middle of the back. The underside is brown and spotted with light brown or orange. It has long, thin legs and long, knobby toes. The toes on the front feet have no webs, but the toes on the back feet do have some webbing. Females are larger than males. Males reach 1.8 to 2.0 inches (4.3 to 5.0 centimeters) long, but females grow to 2.3 to 2.7 inches (5.7 to 6.6 centimeters) in length.

Geographic range: The Sumaco horned treefrog lives in northwestern South America, including parts of Ecuador, Peru, and Colombia.

Habitat: This frog can be found climbing through moist forests of lowland areas or low on mountains. It does not mate or have its young in the water.

Diet: With its large mouth, this frog is able to eat large arthropods, as well as small lizards and other frogs.

Behavior and reproduction: The Sumaco horned treefrog is active at night, when it moves through the trees of the forest. When it stays still, its body color and shape blend into the leaves. If a predator approaches, the frog will open its quite large mouth to flash its bright yellow tongue. This display may startle a predator and convince it to leave the frog be. Like the female Riobamba marsupial frog, the female Sumaco horned treefrog carries her eggs on her back, but the Sumaco horned treefrog does not have a pouch. Instead, the eggs stick to the top of her back. A typical female has about twenty-six large eggs at a time. The eggs skip the tadpole stage and hatch right into froglets.

Sumaco horned treefrogs and people: People rarely see or bother this frog.

Conservation status: The Sumaco horned treefrog is not considered endangered or threatened. ∎

HOURGLASS TREEFROG (Hyla leucophyllata): SPECIES ACCOUNTS

Physical characteristics: The hourglass treefrog, which is also known as the Bereis' treefrog, is a small, slender, reddish brown frog that looks as if someone has dabbed it with streaks of cream or yellow paint. A triangle of color covers the head from one of its large eyes to the other and down onto its short, rounded snout. The color continues down each side of the smooth body, leaving a somewhat hourglass-shaped patch of brown in the middle of the back. An oblong cream or yellow patch sits on the rump, and additional rounded or oblong patches dot the front and back legs. It has long, thin legs, and its toes are tipped in rounded pads. In some individuals, the toes are yellow. The undersides of its legs are orange, as is the slight webbing between its toes. Males are 1.3 to 1.5 inches (3.3 to 3.6 centimeters) from the snout to the rump. Females are larger at 1.6 to 1.8 inches (4.0 to 4.4 centimeters) in length.

Geographic range: This treefrog makes its home in northern South America, from northern and western Brazil through Bolivia to Peru, and also in Colombia, Ecuador, Suriname, French Guiana, and Guyana.

Habitat: It lives in hot and humid, lowland rainforests. Tadpoles develop in shallow ponds.

Diet: It mainly eats moths, but will also eat other small insects. Tadpoles swim to the pond bottom and feed on large bits of plants and other items underwater.

Behavior and reproduction: The hourglass treefrog is active at night, when it climbs through trees looking for food. To mate, a male begins calling from a spot in plants above a pond. His call may be three to eight notes long, with the first being the longest. When a female approaches, he positions himself on her back, clutching her near her front legs, and she lays her eggs. One female can lay about six hundred eggs, which she drops onto the plants. In five to seven days, the eggs hatch into tadpoles, which plop down into the water below.

Hourglass treefrogs and people: It is occasionally seen in the pet trade.

Conservation status: The IUCN does not consider this frog to be endangered or threatened. ∎

AMAZONIAN SKITTERING FROG (Scarthyla goinorum): SPECIES ACCOUNTS

Physical characteristics: The Amazonian skittering frog is a small and slender frog. Its head, back, and legs are light green and grainy-looking. Its head has a small, somewhat pointed snout and two large eyes, one on each side. The legs are thin, and the hind legs are long. All of its toes are webbed and have small rounded pads at the tips. Brown and white stripes run from the chin down the sides of its body. Its underside is white. Males, which grow to 0.6 to 0.8 inches (1.5 to 2.0 centimeters) long, are slightly smaller than females. Females reach 0.7 to 0.9 inches (1.8 to 2.3 centimeters) in length.

Geographic range: It lives in western South America, including far western Brazil, Bolivia, Colombia, and Peru.

Habitat: This small frog lives among the leaves of plants that stretch along and over ponds in warm and humid lowland rainforests.

Diet: It mainly eats spiders, but also eats other small arthropods.

Behavior and reproduction: Active at night, it either sits among leaves that hang low over ponds or skitters across the water. When it skitters, it scoots across the surface of the water without sinking. To attract females for mating, the male makes his whistling calls with a pattern of eight to ten notes in a row. Each female lays 130 to 202 small eggs, which she drops in the pond water. The eggs hatch into tadpoles, each of which is able to flip its strong tail and soar free of the water and through the air, sometimes eight to twelve inches at a time. Usually, however, the tadpoles stay in the water, swimming just below the surface.

Amazonian skittering frogs and people: Although it is quite common, people rarely see this frog.

Conservation status: The Amazonian skittering frog is not considered endangered or threatened. ∎

YUCATECAN SHOVEL-HEADED TREEFROG (Triprion petasatus): SPECIES ACCOUNTS

Physical characteristics: The Yucatecan shovel-headed treefrog is a slender frog with a flattened head somewhat shaped like the blade of a shovel. It is sometimes called a duckbill frog or a casque (kask)-headed frog. The head has a flat outer rim on the snout and a V-shaped ridge on the top of the snout. The large, copper-colored eyes are set far apart on the sides of the head. Its hind legs are long and thin, but its front legs are strong. The toes on all four feet are widened at the tips into round pads. The front toes have little webbing, but the back toes are about two-thirds webbed. The frog is tan to dark brownish green with brown spots on its back and blotches on its legs. Its belly is white, and the bottoms of its legs are tan, sometimes with a pink tint. Females, which reach 2.6 to 3 inches (6.5 to 7.5 centimeters) long, are larger than males. Males grow to 2 to 2.5 inches (4.8 to 6.1 centimeters) in length.

Geographic range: It is found in far southern Mexico, as well as Guatemala and Belize in Central America. A small population also survives in northwestern Honduras.

Habitat: It lives in fairly dry, shrubby forests and grasslands. Eggs and tadpoles develop in pools of water that form in the rainy season.

Diet: Like many other treefrogs in this family, it eats small arthropods. It also sometimes eats other, smaller frogs.

Behavior and reproduction: It is active at night, when it moves across the ground and through shrubs and low trees, looking for things to eat. Its body color provides excellent camouflage when it sits still against the trunk of a tree. After heavy rains create small pools on the ground, all of the males hop near the pools and begin calling from land and in bushes and trees. Each male's call is a duck-like quacking sound. Together, the males sound like a whole flock of ducks. The females approach the males and mate with them, laying their eggs in clumps in the water. All of the frogs mate in about a one-week period. The eggs hatch into tadpoles that remain in the pool until they change into froglets.

Yucatecan shovel-headed treefrogs and people: It is a very common frog that is often seen near towns.

Conservation status: This frog is not considered threatened or endangered. ∎

WATER-HOLDING FROG (Cyclorana platycephala): SPECIES ACCOUNTS

Physical characteristics: The water-holding frog is a chubby frog that has a round but flattened body. Its head blends into its body and does not have an obvious neck. Its eyes sit toward the top of the head. Its legs are strong, but rather short, almost disappearing under the body when the frog is sitting still. Each hind foot has a bump, or tubercle, that is shaped like the edge of a shovel blade. The toes are webbed. The frog is dark brown, gray, or green with dark blotches on its back. It usually becomes greener in the mating season. Its underside is white. Females are the larger sex. Females grow to 2.0 to 2.9 inches (5.0 to 7.2 centimeters) in length, while males reach 1.7 to 2.6 inches (4.2 to 6.4 centimeters).

Geographic range: The water-holding frog lives in three parts of Australia: a large area of the far west, a small spot in the north, and a large area in the middle of the continent from the center to the east.

Habitat: It spends much of its life beneath the ground of deserts and dry grasslands. During the rainy season, males and females come to the surface to mate and have their young in new, small pools of water that have filled with the rain.

Diet: It eats various arthropods that it finds during the rainy season.

Behavior and reproduction: The weather for most of the year is very dry where this frog lives, and the frog survives by digging with its hind feet and tubercles and burrowing backward into the soil to bury itself. Once dug in, sometimes as much as 3.3 feet (1 meter) deep, it sheds a few layers of skin, which harden into a cocoon that keeps its body from drying out. The frog enters a deep resting stage, called estivation, and remains in that state until the rainy season begins. In some years, even the rainy season is not wet enough, and the frogs stay underground for the entire year to wait for the next heavy rains.

When the rains fall hard enough to make shallow pools on the ground, the frogs crawl out from underground. The males call with long, snore-like sounds. Females find the males and mate with them. Each female lays clumps of eggs—sometimes several hundred—in the pools. The eggs hatch into tadpoles, which must turn into frogs before the pools dry up. This can take as little as thirty days. As the rainy season ends, the frogs fill their bodies with water before digging back underground to wait for the next bout of wet weather.

Water-holding frogs and people: Native people, called Australian aborigines (ab-or-RIJ-ih-neez), live in the same area as the frogs. The people sometimes dig the animals from their underground burrows and squeeze them to get a sip of water out of the frog.

Conservation status: The water-holding frog is not considered threatened or endangered. ∎

GREEN TREEFROG (Litoria caerulea): SPECIES ACCOUNTS

Physical characteristics: The green treefrog, also known as White's treefrog, is a pudgy animal with skin that drapes over its sides to make the frog appear almost as if it were melting. The flabby-looking skin behind each side of the back of the head covers large, flat, poison glands. The green treefrog is a round frog with a head that blends back into the body rather than having an obvious neck. Its head has large, white eyes, a short snout, and a wide mouth. Its eardrums are visible on the sides of its head. Its legs are rather short, but its webbed toes are thick and long, ending in wide, triangular-shaped pads. The typical green treefrog is the color of a lime, sometimes with a tinge of yellow on its face and legs. It has a grayish or yellowish white underside. Females, which grow to 2.9 to 4.5 inches (7.0 to 11.0 centimeters) long, are larger than males. Males reach 2.7 to 3.1 inches (6.6 to 7.7 centimeters) in length. Sometimes this frog is listed with the scientific name Pelodryas caerulea instead of the name listed here.

Geographic range: It lives in northern and eastern Australia and has also been introduced to New Zealand.

Habitat: It spends most of its life in the trees of forests, which may be dry or humid. Eggs and tadpoles develop in the calm water of swamps or slow streams.

Diet: This rather large frog eats various arthropods, as well as larger organisms, such as other frogs and even small mammals.

Behavior and reproduction: It often sits in trees with its front feet crossed and held close to its body. It becomes active at night. Following rains, usually from November until February or March, the males begin calling with a deep, repeated "crawk" or barking sound. They call from spots near the water. Females follow the calls to the males and they mate. The females may lay as few as two hundred eggs or ten times that many, dropping them onto the surface of calm water. The eggs soon sink and later hatch into tadpoles. The tadpoles turn into froglets in about six weeks.

Green treefrogs and people: The skin of this frog oozes a substance that can help control high blood pressure in people. High blood pressure, which happens when the blood moves with too much force through the blood vessels in the body, is a dangerous condition. Scientists now make the frog's skin substance in laboratories as a human drug.

Conservation status: The green treefrog is not considered threatened or endangered. ∎

PARADOX FROG (Pseudis paradoxa): SPECIES ACCOUNTS

Physical characteristics: The paradox frog, also known as the paradoxical frog, has large, bulging eyes on the top of its head and a rounded and somewhat pointed snout. It has long and powerful hind legs and shorter but still strong front legs. Its toes are webbed. Its back is light brown to greenish brown, sometimes with light-colored stripes, and its underside is white. Females grow to 1.7 to 3.2 inches (4.0 to 6.5 centimeters) from snout to rump, while males reach 1.6 to 2.7 inches (3.8 to 6.5 centimeters) in length.

Geographic range: Populations of this frog are scattered through parts of northern and central South America, from Uruguay and southern Brazil in the south to Venezuela in the north.

Habitat: It lives in grassy or open forest areas near marshes, ponds, or slow-moving creeks.

Diet: It eats water-living arthropods, as well as small frogs.

Behavior and reproduction: This frog remains in the water most of the time, often with just its eyes poking above the surface. It is mainly active at night except during its breeding season, when the males may make their loud, croaking calls at any time of night or day. Females come to the males and mate with them, laying their eggs among the plants that grow in the water. The eggs, which are grouped together in foamy clusters, hatch into tadpoles. Tadpoles continue to grow in the water and can reach lengths of 11 inches (27 centimeters) before changing into froglets. Much of the length of the tadpole is in its tail, and once that shrinks away, the froglet is much smaller.

Paradox frogs and people: Some local people eat the large tadpoles of this species.

Conservation status: The paradox frog is not considered threatened or endangered. ∎