In the context of discussing the eight sheratzim (creeping creatures) all of whom will render someone who touches them to be tameh (ritually defiled), if they are dead – see Sefer Vayikra 11:29-30 – the Gemara relates the following:
Our Rabbis taught: ‘The tzav after its kind’ (Vayikra 11:29) includes the arod, the nephilin, and the salamander. When Rabbi Akiba read this verse he used to say: ‘How manifold are Thy works, O Lord! Thou hast creatures that live in the sea and Thou hast creatures that live upon the dry land; if those of the sea were to come up upon the dry land they would straightway die, and if those of the dry land were to go down into the sea they would straightway die. Thou hast creatures that live in fire and Thou hast creatures that live in the air; if those of the fire were to come up into the air they would straightway die, and if those of the air were to go down into the fire they would straightway die. How manifold are Thy works, O Lord!’
Salamander is the common name applied to approximately 500 species of amphibians with slender bodies, short legs, and long tails. The common (or “fire”) salamander, salamandra salamander, lives in and around rivers and swamps in Israel and around the world. There is a superficial resemblance to lizards, but they have no scales and their skin is covered with moist mucous. This salamander is mentioned in the same context as the mythical “salamandra of fire,” which is described in the Midrash. Some suggest that Rabbi Akiva’s reference is to the common salamander, which was seen as fire-proof because of its moist body; however, the description of this creature in the Midrash cannot be reconciled with that idea.
The Hatam Sofer suggests that the salamander mentioned by Rabbi Akiva lives in places where there are active volcanoes, and only in these climates can such creatures survive.