Other than that link posted by Lin, I have been unable to find photos of this plant as Desmodium floridanum. In that link it is ID'd as D. floridanum but since I can find nothing else, I consider that a weak reason by itself to base my ID on it. I found some sample in the herbararium but again, they do not state anything about the leaf sizes. I need to find some bonafide reference to the leaf size & I have searched high & low & come up empty.
@JRsbugs can you possibly locate any references? You are so good at coming up with photos & references.