The orchid Zygopetalum Sedenii is a hybrid in the Zygopetalum genus. registered with the Royal Horticultural Society by Veitch in 1874. Registered parents are Zygopetalum mackayi (syn Zygopetalum maculatum) × Zygopetalum maxillare. The key influencing species of this hybrid are No items in the list. listed in order of their genetic contribution.