PlantaeDB Logo
Login Sign-up

Genus Calibrachoa in Tribe Petunieae

In botanical taxonomy, a genus (plural genera) is a rank used to group closely related species within a family. In the hierarchy, genus sits below family and above species.

Genera are defined by shared morphological, anatomical, and genetic characteristics (for example, features of flowers, fruits, seeds, or leaves) that indicate a close evolutionary relationship among the species they contain.

Each genus can include one or more species. Examples include Rosa (roses) and Solanum (nightshades, including tomato and eggplant).

Do you wish to read more about plant taxonomy? Click here!

Genus Description

Suggest a correction!

Calibrachoa (authority Cerv. ex Kunth) belongs to Solanaceae and comprises about 18–22 herbaceous species native chiefly to southern South America, with centers of diversity in southern Brazil, Uruguay, and northeastern Argentina and secondary occurrences in Bolivia, Paraguay, and Chile; a few taxa are cultivated globally. The type is Calibrachoa spathulata Hook. (Hunziker 2001). The genus is distinguished by its low, often somewhat woody-based or suffrutescent habit, with simple, entire leaves lacking stipules; sessile or subsessile blades are commonly oblanceolate to spatulate with cuneate bases. The inflorescence is a reduced cyme or solitary flower; calyces typically enclose the bud and, in some species, the corolla at anthesis, and the corolla is small, rotate to shallowly campanulate, five-lobed, white to lavender, usually with a yellow throat. The ovary is bilocular with axile placentation and numerous ovules, and the fruit is a dehiscent capsule. These features, together with chromosome number x = 9, separate Calibrachoa from its close relative Petunia, which has larger, longer corollas that exceed the calyx and usually x = 7 (Olmstead & Bohs 2007).

Diversity and range are concentrated in temperate to subtropical grassland, campo, and disturbed habitats, with numerous species from lowlands to moderate elevations in southern Brazil and the Uruguayan-Argentine pampas; several taxa are regional endemics (WFO 2024). Lacking broad pan-tropical distributions, the genus shows clear phylogeographic structure, with lineages segregated by major river basins and coastal versus inland areas (T贵的的reply, Floyd & Olmstead 1997).

Intrinsic biology is dominated by insect visitation, with widespread use in horticulture and relatively recent domestication driving trait selection for compact habit and abundant flowering (Floyd & Olmstead 1997). Base chromosome number is well supported as x = 9 (Olmstead & Bohs 2007).

Taxonomy and phylogeny place Calibrachoa within the petunioid clade, resolved as sister to Petunia in multiple molecular analyses (Olmstead & Bohs 2007; Olmstead et al. 2008). The genus has been treated in a broad sense, with synonymization of several segregate names (WFO 2024). Divergent clades are well sampled, but some species boundaries remain to be fully resolved (Floyd & Olmstead 1997).

Human relevance is primarily horticultural, since C. × hybrida and selections derived from it are globally used as ornamental bedding plants and container subjects (Floyd & Olmstead 1997).

Conservation and outlook include regional endemics subject to habitat loss from agriculture and urbanization; better-supportedRed List assessments and targeted field surveys are priorities (POWO 2024).

Pick a Species to see its components: