The word "amphibian" comes from a Greek word meaning “double life.” This term reflects how most amphibians begin their lives in water, breathing with gills, then later mature into land animals that breathe with lungs (though most still stay near water).
Amphibians belong to the class Amphibia, which has three orders:
Anura: This order consists of tailless amphibians—namely, frogs and toads.
Caudata: These are the tailed amphibians—namely, salamanders, newts, and sirens.
Gymnophiona: This order consists of legless, tailless, burrowing amphibians, which are called caecilians.
Roughly 5,000 species of frogs and toads are known to exist, and there are about 500 species of salamanders, newts and sirens. Caecilians are the least common amphibians, at about 160 species.
Most common amphibian types
Similarities and Differences Between Frogs and Toads
Similarities | Differences | |
|---|---|---|
__________________________________________________ | ||
Frogs | Toads | |
Both hatch from eggs Young have gills Adults have lungs Young live in water | Lay eggs in clusters | Lay eggs in chains |
Teeth in upper jaw | No teeth | |
Moist, smooth skin | Dry, lumpy skin | |
Jump | Walk | |
Bulging eyes | Eyes don't bulge | |
Some Common Salamandersa and Newts
Type | Location | Habitat | Length |
|---|---|---|---|
Axolotl salamanderb | Native to Xochimilco and Chalco lakes, Mexico City | Strictly aquatic habitats | 8–11 in (20–28 cm) |
Blackbelly and shovelnose salamanders | Appalachia; springs and streams | Springs and streams | Blackbelly: 3.9–7.1 in (10–18 cm) Shovelnose: 3.5–5.0 in (9–12.5 cm) |
Eastern hellbender salamander | Eastern United States | Fast-moving, clear streams; under large flat rocks | 12–29 in (30–74 cm) |
Marbled salamander | Southern New England and west to parts of Texas, Illinois, and Oklahoma, and south to northern Florida | Variety | Up to 4.25 in (11 cm) |
Ozark hellbender salamander | Southern Missouri and northern Arkansas | Fast-moving, clear streams; under large flat rocks | 11–22 in (28–56 cm) |
Redback salamander | Canada and northern United States to Midwest | Woodlands | 2.6–4.9 in (6.5–12.5 cm) |
Seal salamander | Southwestern Pennsylvania to Georgia and Alabama | Streams, ravines, and similar habitats | 3.3–5.0 in (8.3–12.5 cm) |
Tiger salamanderb | Western-central Canada south to Mexico and east and north to Long Island, New York | Sandy soils | Varies by type; up to 12 in (30 cm) |
Two-lined and Junaluska salamanders | Limited range in Tennessee and North Carolina for Junaluska, broader range for Two-lined | Junaluska: lower-elevations (< 2,395 ft, or 730 m); rocky, wide-basin streams and forests Two-lined salamander: woodlands, stream banks | Up to 4.7 in (12 cm) |
California newt | California and west coast of United States | Small ponds and creeks, moist woodlands | Up to 8 in (20 cm) |
Eastern or red-spotted newt | Eastern half of North America, southern Canada, Texas, Oklahoma, and Florida | Watery areas | 2.25–5.0 in (5.7–12.7 cm) |
Fire-bellied newtb | China and Japan; | Still-water habitats such as ponds, rice terraces, forest ditches | Varies; generally 3–5 in (8–13 cm) |
Rough-skinned Oregon newt | Coastal Pacific Northwest from southeast Alaska to San Francisco, California | Aquatic habitats or woodlands | 5.0–8.5 in (13–22 cm) |
a Salamanders should never be taken from the wild, because some species are illegal in some US states. b Common as pets. |
Amphibians vary widely in size and color. The largest are the Chinese and Japanese giant salamanders, which reach 6 feet (1.8 meters) long and weigh up to 140 pounds (63 kilograms). The smallest amphibians are the tiny poison dart frogs, which are less than ½ inch (1.3 centimeters) long and weigh only about an ounce (3 grams).
Most amphibians have moist skin coated with a mucus film known as a slime layer. Adult amphibians breathe through lungs and also through their skin, which must stay moist for oxygen exchange. Lifespans range from months to many years.
Amphibians can be good pets, but they should be handled as little as possible because their skin is delicate. Some amphibians release irritating toxins from their skin or glands, so humans should wear powder-free disposable gloves—moistened with either water from the animal's own enclosure or commercially available chlorine-free water—before handling amphibians or cleaning their enclosures, to protect both themselves and their pets.
Injuries
Typical injuries to pet amphibians include cuts, fractures, internal bleeding, drying out (desiccation), and loss of toes, limbs, or tails. Prompt veterinary care and support is essential for an injured amphibian.
Desiccation is common in amphibians that escape their enclosures or that are housed improperly (see Housing for Amphibians).
Fractures in small amphibians (weighing less than 1 ounce, or 30 grams) can often be treated with rest, but fractures in larger amphibians may require casts or internal pins.
Pain control is important for injuries. Amphibians have opioid receptors, so your vet may prescribe opioids for pain. Your vet may also recommend anti-inflammatory drugs, such as meloxicam. Regardless of the medication, never give your amphibian drugs without consulting with your veterinarian.
