PlantaeDB Logo
Login Sign-up

Genus Coptosperma in Family Rubiaceae

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!

Coptosperma Hook.f. (Rubiaceae, tribe Coptosperma) contains about twenty accepted species (POWO, 2024; WFO, 2024) and is distributed across tropical Africa from West‑Guinean forests to the Eastern Arc of Kenya and Tanzania (Verdcourt, 1989). Its centre of diversity lies in the Guineo‑Congolian region, with several narrow endemics in the East African highlands.

Diagnostic morphology: Plants are small trees or shrubs with opposite, simple leaves bearing interpetiolar stipules that are triangular to filiform. Inflorescences are terminal paniculate thyrses bearing numerous five‑lobed, actinomorphic corollas that are white to pale yellow, the tube slender and the limb spreading. The ovary is inferior, usually bilocular with axile placentation, and the fruit is a fleshy drupe. These characters—interpetiolar stipules, white tubular flowers, and an inferior bilocular ovary—distinguish Coptosperma from the closely related Aulacocalyx, which typically has a longer corolla tube and a superior ovary (Govaerts et al., 2023).

Diversity & range: The genus occupies lowland to mid‑elevation rainforests, secondary forest and forest margins up to roughly 1 500 m (Verdcourt, 1989). The West African rainforest belt hosts the greatest species richness, while several species are endemic to the Eastern Arc Mountains, reflecting historical fragmentation of the African rainforest biome.

Intrinsic biology: The white, nectar‑rich flowers suggest insect pollination, and field notes report visits by small bees and flies, though detailed pollinator data remain scarce (Davis et al., 2022). The fleshy drupes are presumably dispersed by birds and mammals, a pattern common in Rubiaceae, yet quantitative dispersal studies are lacking.

Taxonomy & phylogeny: Coptosperma is treated as a monotypic genus without formal subgeneric ranks (Govaerts et al., 2023). Molecular phylogenies confirm its monophyly within tribe Coptosperma but unresolved deep nodes preclude a robust infrageneric classification (Davis et al., 2022). Historically, some authors synonymised the genus with Aulacocalyx (e.g., Hallé 1978), an arrangement now rejected by contemporary revisions (POWO, 2024).

Human relevance: No Coptosperma species is cultivated as an ornamental or commercial crop; a few are locally harvested for timber or fuel, but the genus has negligible economic significance (Verdcourt, 1989). It is not considered invasive.

Conservation & outlook: Habitat loss from logging and agricultural expansion threatens several endemics, yet comprehensive IUCN assessments are scarce (POWO, 2024). Focused field surveys and taxonomic clarification are essential to develop effective conservation strategies for this understudied genus.

Pick a Species to see its components: