The Space Amoeba

Spore creatures take control of a space probe headed to Jupiter and turn it back towards earth. Crash-landing off an island being studied for a resort's development, the alien life forms take over and enlarge three local creatures, a squid (Gezora), a crab (Ganime) and a snapping turtle (Kameba, who later went on to make a brief appearance in Tokyo SOS). A scientist and Photographer fight to save the island from the giant mutants as they try to figure out how to stop the alien life force. (official distributor synopsis)