 
Saliguana was a hybrid of an iguana & a mythical salamander, capable of living in & breathing fire. He could also extend his tongue & use it as a rope. Salaguana was created by Lord Zedd from Miss Appleby's pet iguana. After Salaguana terrorized Bulk & Skull, he fought Zack & Billy. Because of the iguana half, Saliguana was cold-blooded and therefore his powers would be weakened by cooler temperatures. Zack and Billy finally extinguished his flame breath with an ice weapon & assaulted him with the Power Blaster, weakening him to the point of his near destruction, forcing Zedd to make him grow. After the ensuing battle, which involved the Saliguana's tongue being severed after binding the Thunder Megazord with it (and eventually planning to eating it, as inferred by Saliguana stating "Ah! Lunch!" right before his tongue was chopped in half), the Thunder Megazord destroyed Saliguana with its Thunder Saber.
Because Zedd's magic was lifted, Saliguana reverted back to Miss Appleby's iguana, whom Bulk and Skull attempted to use to track down the Rangers in a failed attempt (although it did clear out everyone but the Power Rangers, Bulk and Skull, and Miss Appleby.
Saliguana was later re-created by Finster to battle the Rangers in the "Specter Theater." After fighting them, Saliguana attended Zedd & Rita's wedding, bringing them a human skull as a wedding gift. When the monsters attacked the Rangers, Saliguana was destroyed, by the Thunder Megazord.
The Saliguana suit was later recycled for the alien creature known as Tritor, in Power Rangers Zeo's "King for a Day"
Note: Saliguana comes from what is commonly referred to as "Zyu2" footage, and was not seen in the original ZyuRanger. Saliguana was intended to be destroyed by the Dino Megazord. Discongruity between the monster and zords also explains why the black tongue of Evil Bookala is shown.