Hopping To It ... Rib-bit, Rib-bit

Some of the world’s most fascinating amphibians hopped into the nation’s Post Offices earlier this month when USPS released its Frogs stamps.

Frogs live on every continent except Antarctica. There are approximately 4,800 different species of frogs, including more than 90 species that live in the United States.

Each stamp features one of four North American frogs:

• The Pacific tree frog (Pseudacris regilla): Known for its familiar “rib-bit, rib-bit” call, this frog is nicknamed the “Hollywood frog” because it’s often featured in movies and television shows that call for nighttime scenes.

• The northern leopard frog (Rana pipiens): This frog is known for its highly distinctive rattle-like snoring noise, followed by several “chuckling” or “clucking” sounds.

• The American green tree frog (Hyla cinerea): Also called the rain frog or the cowbell frog, it’s usually noisy after a warm rain.

• The squirrel tree frog (Hyla squirella): Known for a raspy, quack-like call — much like the scolding noise of gray squirrels — this frog is found from southeastern Virginia through Florida and along the Gulf Coast to Texas.

William J. Gicker designed the stamps based on digital illustrations by Nancy Stahl, who used a palette of green and brown colors to capture distinctive features of each frog.