Daikyojû Gappa (1967) aka Monster From a Prehistoric Planet (repost)

An expedition in the South Pacific lands on a tropical island where the natives worship the mysterious deity Gappa. An earthquake opens up an underground cavern and a baby reptile is ... See full summary »

Director:

 Haruyasu Noguchi

Writers:

 Ryûzô Nakanishi, Gan Yamazaki

Stars:

 Tamio Kawaji, Yôko Yamamoto, Yuji Okada - via IMDB 

https://archive.org/details/Monster_From_a_Prehistoric_Planet