Amphibians are cold-blooded vertebrates that require water for survival. Their skin is smooth, lacking scales or feathers.

Amphibians possess a special system of skin glands that produce mucus, allowing them to breathe through their skin instead of their lungs. This adaptation enables them to live in both water and land environments.

Oacian

The Oacian is an amphibian species native to Costa Rica that was first observed in the wild. Males feature bright orange dorsum coloration while females are dark to pale olive with red spots edged in yellow (Savage 1966).

This terrestrial, diurnal animal inhabits forests and along streams. It communicates with other males by waving its forefeet and emitting a soft trilled call.

Oacians breed rapidly during April through June during wet, heavy rainy seasons, congregating in large numbers around ground puddles. Competition between males and females is fierce, often with males outnumbering them by an 8:1 ratio.

Females lay 200-400 eggs each week for six weeks, each measuring 3mm in diameter. These eggs are placed into small pools no deeper than an inch, and the tadpoles emerge after only a few days. It takes these tadpoles another four or five weeks to fully develop.

Green tree frog

The green tree frog is a member of the frog family and often found near ponds, lakes, rivers and streams. They prefer habitats with plenty of floating plants like lily pads or duckweed.

These amphibians require clean water, especially during breeding season. Males sit atop floating plants near a small body of water and emit an insistent bell-like call to attract females.

During breeding season, female frogs lay 400 to 600 soft-shelled eggs that hatch into tadpoles after several weeks. Throughout their lifecycle, these amphibians will consume various insects.

Frogs live in a variety of habitats, from forests and woodlands to swampy edges of watercourses. Some even take refuge near suburban houses, drainpipes, water tanks and letterboxes.

Hellbender

Hellbenders are a type of salamander found throughout the United States. They’re sometimes referred to as “mud devils,” “devil dogs” or “ground puppies.”

These salamanders are the largest species found in North America, growing up to 30 inches long and weighing up to 5.5 pounds.

The hellbender differs from most salamanders in that it breeds by external fertilization. Male hellbenders dig a brood site under a log or rock that faces downstream during their breeding season.

The female then produces 150 to 200 eggs. The male then positions himself slightly above or alongside the eggs and sprays them with sperm.

These solitary creatures spend most of their lives on the river bottom, though some may also climb trees to escape predators. Dams and water pollution have been identified as two primary factors contributing to declines in their population.

Axolotl

Axolotls are gilled, aquatic salamanders. Unlike most amphibians, they don’t go through metamorphosis and can live in water all of their lives.

They possess feathery gills which they use for breathing. Furthermore, these animals can take oxygen directly from the water’s surface – an adaptation that allows them to survive in low oxygen environments.

Their skin is a combination of olive-tan with gold patches. Genetic mutations can alter their hue, such as leucistic, golden albino or xanthic forms.

Carnivorous, they eat a wide range of foods such as small fish and brine shrimp to worms and snails. When hungry, axolotls may even engage in cannibalism by biting off parts of family members to gain nourishment; this can lead to injury but the ability for regrowth after injury.