The amphibians are the oldest class of terrestrial vertebrates - the first to bridge the gap between the land and sea, and in their time the dominant order on the last with species reaching up to 30ft long.  However, in the modern world they are essentially small species with even the largest species being only 180cm long at most - significantly smaller than the largest fish, reptiles, birds or mammals.    They are represented by 3 modern orders - Urodela (newts and salamanders), Anura (frogs and toads) and Apoda (caecilians) totaling around 7000 species.  They are perhaps most notable for going through an aquatic larval stage before developing into a full adult - something that no other vertebrate order does.

URODELA - The Newts and Salamanders
Salamanders are superficially lizard like amphibians found primarily in the Northern hemisphere, They are found in both fresh water and on land, but also a number of species are subterranean, dwelling in water filled underground caves.   There are 655 known species with a particular concentration in North America which contains one third of all species.

Great Crested Newt (Triturus cristatus)
Smooth Newt (Lissotriton vulgaris)

ANURA - The Frogs and Toads
The frogs and toads represent 90% of the species of Amphibian - they are short bodied, tailess ampbians as adults, primarily associated with fresh water. They are very varied and can be found in a wide range of habitats including fresh water, dry land and trees.  There is no actual differentiation between frogs and toads - it tends to be that wartier species and named toads and smoother frogs without any actual taxonomic relevance.

Banded Bullfrog (Kaloula pulchra)
Common Frog (Rana temporaria)

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