Pachycereus
Pachycereus is a genus of 9–12 species of large cacti native to Mexico and just into southern Arizona, United States. They form large shrubs or small trees up to 15 m tall, with stout stems up to 1 m in diameter. Pachycereus comes from the ancient Greek παχύς meaning "thick" and the Latin cereus meaning "torch".
Species
| Image | Scientific name | Common Name | Distribution |
| Pachycereus fulviceps D.R.Hunt | Mexico | ||
| Pachycereus gatesii D.R.Hunt | Mexico | ||
| Pachycereus gaumeri Britton & Rose | Morelos, Puebla - Mexico | ||
| Pachycereus grandis Rose | Mexico | ||
| Pachycereus hollianus Buxb. | Mexico | - | |
| Pachycereus lepidanthus Britton & Rose | Guatemala; Honduras | ||
| Pachycereus marginatus Britton & Rose | Mexico | ||
| Pachycereus militaris D.R.Hunt | Colima, Guerrero, Jalisco and Michoacán states of México | ||
| Pachycereus pecten-aboriginum Britton & Rose | Indian comb | Mexico | |
| Pachycereus pringlei Britton & Rose | cardón cactus | states of Baja California, Baja California Sur, and Sonora Mexico | |
| Pachycereus schottii D.R.Hunt | totem cactus, senita cactus | southern Arizona and north-western Mexico, particularly Baja California and Sonora. | |
| Pachycereus tepamo Gama & S.Arias | Mexico | ||
| Pachycereus weberi Backeb. | Mexico |
P. pringlei is the tallest cactus species in the world, with a maximum recorded height of 19.2 m.
;Synonymy
These genera have been brought into synonymy with Pachycereus:
- Backebergia Bravo
- Lemaireocereus Britton & Rose
- Lophocereus Britton & Rose
- Marginatocereus Backeb.
- Mitrocereus Backeb.
- Pterocereus T.MacDoug. & Miranda