Melocactus pachyacanthus subsp. viridis
Melocactus pachyacanthus subsp. viridis in Bradleya 9: 40–41. 1991 sec. Zappi & Taylor 20201
- ≡Melocactus neoviridescens in Cactology 5 (Suppl. 10): 2. 2020 syn. sec. ???2
- ≡Melocactus viridescens in Cactology 5 (Suppl. 8): 3. 2020, nom. illeg., syn. sec. ???2 [non Melocactus viridescens 1845 nec Melocactus viridescens 1845]
- ≡Melocactus pachycephalus in Phytotaxa 470(3): 256. 2020, nom. illeg., syn. sec. ???2