Looking through the USDA Plants listing of
Euphorbia in Florida, and looking more closely, I'd still guess
Euphorbia heterophylla.
Is #5 a different plant than photos 1-4? Or a different part of the same plant?
Here's some info about
Euphorbia cyathophora (which usually has some coloured or white leaves underneath the flowers) and also about
Euphorbia heterophylla, incuding a photo comparing the two:
http://keyserver.lucidcentral....
Anyway, regardless,
Euphorbia heterophylla has variable leaf shape, and it would still be my guess even if these are 2 different plants... might be wrong, as I'm not familiar with these plants.