Brachycereus
| Brachycereus | |
|---|---|
| File:Brachycereus nesioticus.jpg | |
| Kingdom | Plantae |
| Family | Cactaceae |
| Subfamily | Cactoideae |
| Tribe | Phyllocacteae |
| SubTribe | Corryocactinae |
| Genus | Brachycereus |
| Species | |
| Notes | Taxonomy follows Joël Lodé (2015). |
Etymology
The name Brachycereus means "Short wax candle", referring to the relatively small and compact stems of the genus compared to other columnar cacti.
Description
Brachycereus is a monotypic genus that grows in dense, low-lying clumps. The stems are cylindrical, non-articulated, and branch from the base. They feature 18 to 22 low ribs, which are densely covered by stiff, yellow spines that turn blackish with age, almost completely obscuring the epidermis.
The flowers are white and emerge near the base of the stems. There has been debate regarding their opening times; however, recent observations suggest they open around 9:00 PM and stay open until nearly noon the following day. While they may be pollinated by insects similar to those of Jasminocereus, some observers suggest that ants (Camponotus sp.), which are active both day and night, may play a significant role. The fruits are fleshy and reddish when mature, covered with deciduous (falling) spines. The seeds are small, ovoid, and dark brown.
Habitat
The genus is endemic to the Galápagos Islands, where it grows from sea level up to approximately 500 m in altitude. It is a pioneer plant, often being among the first to colonize recent lava flows. It grows exclusively in extremely arid areas, thriving in full sun within the crevices of volcanic lava fields.
Distribution
- Ecuador (Galápagos Islands: Fernandina, Genovesa, Isabela, Pinta, Santa Cruz, Santiago)
Species
The genus contains only one recognized species:
Notes
- DNA sequences (Wallace, 2002) have determined that Brachycereus and Jasminocereus are closely related, with their nearest mainland relative being Armatocereus, found on the coasts of Ecuador and Peru.
- Morphologically, Brachycereus nesioticus shows some similarities to the genus Haageocereus, leading to theories that it might be a stabilized hybrid of a now-extinct parent.
- Although currently placed within the tribe Phyllocacteae (subtribe Corryocactinae), some researchers note that the current assemblage of this subtribe may be polyphyletic.
