This would be a pointer that points to a struct body.
The way you've declared it, newHeadptr could point to a struct body. Remember, though, that you haven't allocated a struct body for it to point to. Initially, newHeadptr will just have some garbage value. To rectify that, you could to this:
headerptr newHeaderptr = malloc(sizeof(*newHeaderptr));
or:
struct body newBody;
headerptr newHeaderptr = &newBody;