Spotted Silver Dollars And Spotted Metynnis

[Goggy]

I wanna know the difference in these two fish Metynnis Lippincottianus ( Spotted Silver dollar ) and the Metynnis Maculanntus ( Spotted Metynnis ) to me they look the same from google images, but i know there not. i want to know which one is more "Spotted" which one is smaller, which one is more Flashy in color and how to tell the difference
Thanks!
Goggy
 
I like this one best but i dont know what type it is please identify it:
 

 
btw i changed My profile pic