These 2-ribbed cactus epiphytes with similar undulating rib margins are Disocactus (Nopalxochia) ackermannii (upper shoot) and D. nelsoni (lower shoot).
These 2-ribbed cactus epiphytes with similar undulating rib margins are Disocactus (Nopalxochia) ackermannii (upper shoot) and D. nelsoni (lower shoot).