A 32-year-old male from rural Odisha presents with fever, chills, and sweating for 3 days. He reports that the fever occurs every alternate day with a regular pattern. Physical examination reveals splenomegaly and mild jaundice. A blood smear prepared during a fever spike shows ring forms and Schüffner's stippling. Which Plasmodium species is most likely responsible, and what is the significance of the fever pattern?