By some definitions, there are possibly over one thousand different sub species of the Human race in the Union. The reasons for the uncertainty is in large part due to the the minor genetic tailoring some Terran Human colonists received during the Second Exodus and disagreements on how much change would be needed for those colonists to be considered sub species.
Under more rigid definitions, it includesTerrans, the 41 Clone Species, the Sarans/Pan Sarans, the Saresii the Celtest, and the Mini Terrans.