Plasmodium vivax and falciparum differentiation?

Hello everyone,

I'm learning Malaria right now, and thought it would be good for me to differentiate plasmodium vivax and plasmodium falciparum.

P.V

Produces benign tertian malaria,

Some sporozoites remain as hypnozoites,

Merozoites enter new RBCS

Ring stage, amoeboid, shizont, gametocyte can be identified using microscope

P.F

Produces malignant tertian malaria,

Cause more severe infection

No hynozoites,

Merozoites enter RBC of all ages

Only ring stage and gametocyte can be identifed using microscope

Now my questions are,

1. What is the difference between malignant and benign malaria? Malignant one obviously sounds bad but what is the exact difference.

2. Now why are amoeboids and shizonts not seen with P.F. To complete the life cycle these stages must occur right, are these stages occuring with plasmodium falciparum, if so why can't we see it in peripheral blood.

Also if there are any difference between too, please add. Thank you