Cumarinia
| Cumarinia | |
|---|---|
| File:Cumarinia odorata.jpg | |
| Kingdom | Plantae |
| Family | Cactaceae |
| Subfamily | Cactoideae |
| Tribe | Cacteae |
| SubTribe | |
| Genus | Cumarinia |
| Species | |
| Notes | Monotypic genus. Taxonomy follows Joël Lodé (2015) and Breslin et al. (2021). |
Etymology
The name is derived from **coumarin**, an aromatic chemical compound found in plants like tonka beans (Dipteryx odorata) and fragrant bedstraw. The flowers and fruits of this genus produce a similar scent, which is used industrially for flavoring.
Description
Cumarinia is a monotypic genus containing only the species Cumarinia odorata. It consists of small, globose to short-cylindrical plants that cluster from the base.
Key morphological features include:
- **Tubercles:** Long, soft, and cylindrical, each featuring a distinct longitudinal groove (furrow).
- **Spines:** Long, fine, and notably **hooked** at the tips, resembling fishhooks.
- **Flowers:** Small, diurnal, and self-fertile. they emerge from the base of the tubercle groove and are typically yellowish-pink or cream-colored with a strong fragrance.
- **Fruits:** Distinctive cylindrical berries that start as carmine red before turning dark. They are fragile and highly fragrant.
- **Seeds:** Tiny, brownish, egg-shaped, smooth, and shiny.
Habitat
The genus grows at altitudes up to 1600 m, specifically on **limestone soils**. Unlike many other desert cacti, it prefers more sheltered positions, growing in rocky crevices or in the shade of larger vegetation. It is often found in pockets of humus that remain relatively humid compared to the surrounding environment.
Distribution
- Mexico: San Luis Potosí and Tamaulipas.
Species
The genus contains only one recognized species:
Notes
- Taxonomic History: This taxon has been moved between Coryphantha, Neobesseya, and Neolloydia. While some authors (Anderson, 2001) merged it into Coryphantha, Joël Lodé maintains it as a separate genus to avoid making Coryphantha polyphyletic.
- Molecular Evidence: Studies by Crozier (2005) and more recently by **Breslin et al. (2021)** confirm that Cumarinia is a distinct lineage within the Mammilloid clade, more closely related to Cochemiea than to Coryphantha s.s.
- Convergent Evolution: The fragrant flowers are considered a result of evolutionary convergence with certain species of Mammillaria.
