Cephalocleistocactus
| Cephalocleistocactus | |
|---|---|
| File:Cephalocleistocactus chrysocephalus.jpg | |
| Kingdom | Plantae |
| Family | Cactaceae |
| Subfamily | Cactoideae |
| Tribe | Cereeae |
| SubTribe | Trichocereinae |
| Genus | Cephalocleistocactus |
| Species | |
| Notes | Taxonomy follows Joël Lodé (2015). |
Etymology
The name Cephalocleistocactus means "Closed head cactus". This refers to the two most prominent features of the genus: the tubular, almost closed flowers (characteristic of Cleistocactus) and the specialized flowering zone known as a pseudocephalium (Cephalo).
Description
Cephalocleistocactus is a monotypic genus of columnar, shrubby cacti that branch primarily from the base. The stems feature low ribs marked by distinctive V-shaped grooves. The areoles bear finely setose (bristle-like) spines.
The flowers are diurnal and self-sterile. They are tubular, bright red, and emerge from a lateral pseudocephalium—a specialized area covered with long bristles. These flowers are adapted for pollination by hummingbirds. The fruits are reddish, containing small, shiny black seeds.
Habitat
This genus is endemic to a very limited area in Bolivia. it grows at altitudes of approximately 2000 m.
Distribution
- Bolivia (La Paz)
Species
Currently, the genus is considered monospecific:
Notes
- The taxonomic position of this genus has been highly controversial. While some authors (Hunt & Taylor) included it within Cleistocactus, others (Mottram, Anderson) maintained it as a separate genus.
- Joël Lodé recognizes it as a correct genus, supported by phylogenetic studies (Schlumpberger et al., 2012) which place it in a clade between Yungasocereus and Samaipaticereus.
- Some researchers, such as R. Mottram, have suggested that the genus might have originated as a natural hybrid between Cleistocactus and Espostoa.
