Salamanders are amphibians and are, despite their appearance, not reptiles or even lizards. There are around 500 different species of salamanders in the world today. Salamanders are found in the order Cuadata but are sometimes referred to as belonging to Urodela. They are divided into 3 suborders and 10 different families.

In most species, the mature salamander will have a body similar to a lizard; i.e. a slender body with four legs and a tail. Most species have four toes on the front feet and five on the back feet. There are however salamander species that, to various degrees, have reduced or absent limbs making them look more like snake or eels. Many species of salamander are brightly coloured and their beauty have turned them into popular pets. There are also colourless and rather dull looking species of salamander but they are not very common in the pet trade.

Most salamanders live on land and are semi-aquatic but there are also species that live below ground. Salamanders can seem slimy and this is due to a mucus they excrete to stay moist on land and help regulate osmosis flows in the water (i.e. retain the right level of salts in the body). This mucus also helps the salamander move more easily through water.

Salamanders often hide and hibernate in old wood which gave birth to the myth that salamanders are born from fire. People put pieces of dry wood on the fire containing hidden salamanders that would crawl out of the fire apparently unharmed.

One third of all known salamander species are native to North America, but salamanders can be found in most places and in both arid and moist environments. They do not live on Antarctica and are absent from most parts of Africa and Australia as well. The greatest concentration of salamander species can be found in the Appalachian Mountains in North America.

Most salamanders grow to be between 10-20 cm / 4-8 in. There are however many species that grow smaller or larger than that. The world’s largest salamander is the Chinese giant salamander which is an endangered species that can grow to a length of 1.8 metres (5.9 ft) and weigh up to 65 kg (140 lbs). The smallest salamander species in the world is the Minute salamander that grows to a total length of 2.7 cm (1.1 in).

Salamanders are a diverse group of animals with very different anatomical characteristics. Some species have lungs while others breathe through gills. There are also species that have both lungs and gills as adults. Interestingly enough, salamander lungs are much simpler than type of lung found in mammals. There are also some species of salamander that lack both gills and lungs and breathe through their skin. Some species with lungs retain this ability to breath through the skin.

Salamanders need moisture to reproduce. Most species deposit their eggs in water but some species use moist dirt and there are also species that give birth to live young after having retained the eggs until they are ready to hatch. Most salamanders use internal fertilization where the male deposit a sperm sac in the female’s cloaca.  However, some of the more primitive species, Cryptobranchoidea, use external fertilization.

Some Salamander larvae are fully aquatic while others are terrestrial depending on species. The larvae of some species have legs. Eventually, the larvae go through a metamorphosis that includes a lot of anatomical changes, with the larvae of different species going through different changes. The larval stage can last anything from days to years depending on the species.