A characterization of betalain and anthocyanin pigments from Christmas Cactus (Schlumbergera buckleyi) and Mammillaria vivapara var. vivapara flower petals by LC/MS-MS/ESI was conducted. The analysis of the Christmas Cactus flower petals by mass spectrometry was compared to previous work. The molecular weights and retention times obtained for betalain and its many isomers allowed the assignment of several previously identified molecules. Further analysis of the data yielded several previously unknown betalain isomers. As reported in the research literature anthocyanins were not found in the mass spectrometry analysis of the Christmas Cactus flower petals. The analysis of the mass spectrometry data for the Mammillaria vivapara petals was carried out and several betalain isomers common to the Christmas cactus were identified. In addition to the expected betalains two anthocyanins were identified in the flower petals. The discovery of these anthocyanins in Mammillaria vivapara var. vivapara is a novel discovery in the species.