>>What is the most unusual species of salamander?
>>I am just curious.
>>
>>Thank you.

Most salamanders look similar. They have 2 pairs of legs and a tail. Therefore the Sirens are quite unusual since they only have a pair of front legs but no rear legs.

Another salamander that is unusual is the Ribbed Newt, Pleuordeles waltl. It has sharp ribs that can pierce the skin and the poison glands in the skin. That is a unique and effective defense against potential predators.

A third unusual species is the Pacific Giant Salamander. It is capable of producing a barking sound when annoyed. Salamanders are often called water dogs by people who are not scientists or naturalists. The Pacific Giant Salamander is one species that actually lives up to that vernacular name.