What are the common groups of amphibians and their representative species?

Amphibians are a group of cold-blooded vertebrates whose larvae live in water and breathe with gills, while the adults mostly move onto land, switching to lungs and relying on their skin to assist respiration. Their skin is bare and moist and can carry out gas exchange, so they usually live in damp environments close to water, and their body temperature changes with the outside temperature.

In terms of classification, living amphibians mainly fall into three major groups. The Anura (tailless amphibians) is the most common group, covering all kinds of frogs and toads; the adults have a reduced tail and well-developed hind legs, making them good at jumping. The Caudata (tailed amphibians) retain a tail throughout life, and representative animals include the Chinese giant salamander, newts and salamanders, and the lesser salamander. The Gymnophiona are slender and shaped like earthworms, mostly burrowing in moist soil; there are fewer species, and they are usually the hardest to see.

In ecosystems, amphibians occupy an important middle position: they prey on insects and other small invertebrates, and they are also prey for animals such as birds and snakes. For farmland, frogs can prey on many kinds of pests and are natural helpers in biological control, which is also why ecological farming methods such as raising frogs in rice paddies have attracted attention. In addition, their skin is fairly sensitive to environmental changes, so they are often regarded as indicator animals reflecting the state of the ecological environment.

As for common questions, the difference between frogs and toads is the one most often raised: frogs have smooth skin and strong jumping ability, while toads have rough skin and mostly move by crawling. It should be noted that the skin secretions of some toads and salamanders contain toxins, so hands should be washed after contact, and eating wild amphibians is not recommended. As habitats shrink and water quality changes, the survival of many amphibians is under threat, and protecting wetlands and water environments is especially important for them.