Reptilicus

Reptilicus, a giant monster film about a fictional prehistoric reptile, is a DanishAmerican coproduction, produced by American International Pictures and Saga Studio, and isupon close examinationtwo distinctly different films helmed by two different directors.

Danish miners Svend Viltorft dig up a section of a giant reptiles tail from the frozen grounds in Lapland, where they are drilling. The section is flown to the Danish Aquarium in Copenhagen, where it is preserved in a cold room for scientific study. But due to careless mishandling, the room is left open and the section begins to thaw, only for scientists to find that it is starting to regenerate.Professor Otto Martens, who is in charge of the Aquarium, dubs the reptilian species Reptilicus upon a reporters suggestion and compares its regeneration abilities to that of other animals like earthworms and starfish. ........

Source: Wikipedia