It appears Barbara is his 1st wife, and probably the mother of his children.
5-27=1890 Melchor m Barbara FLUKE, Fred. Co MD 8-14-1790 Melchor m. Eve Margaret BARE,""
I'm assuming the ch you know are Jacob and Susanna Barbara. A tree on familysearch.org has Melchoir's parents: Henry STALEY/Maria STEINBRUCKEL both b Switzerland.If this is correct, I would assume Melchoir would name ch Henry & Maria.
Another tree, on Ancestry, states Anna Barbara's name is MIZKEL.
Since Melchoir made compensation to his other ch thru son Jacob, you may want to check into court records for dispensation of these monies.