He explained that the bones, which included a skull that was almost complete, were found by a team of scuba divers who were exploring an underwater cave in the area.
“It’s miraculous that they even saw it,” he told BBC News.
“When they discovered it, they were fearful the bones were exposed, so they moved the material to a little nook to protect it.”
Having sought official permission to remove the fossil from the cave, Dr Rosenberger returned to with the scuba divers to retrieve it in October of last year.
The divers packed the skeleton into tupperware boxes in order to bring it safely to the surface.