Researchers report 15 new species of Coleus (Lamiaceae) and revised 95 taxa in Central Africa

NEWS - Researchers revised the genus Coleus (Lamiaceae) in DR Congo, Rwanda and Burundi based on herbarium taxonomy. Pierre Meerts of the Université Libre de Bruxelles in Brussels and Alan Paton of the Herbarium Royal Botanic Gardens in Richmond reported 95 taxa consisting of 89 species, 1 subspecies and 5 varieties.

The report includes 15 new species and one new variety: Coleus duvigneaudii, C. hildei, C. kaminaensis, C. kundelunguensis, C. linarioides, C. lisowskii, C. marunguensis, C. minusculus, C. mitwabaensis, C. mystax, C. pengbelensis, C. piscatorum, C. pseudoschizophyllus, C. ruziziensis, C. zigzag and C. esculentus var. kolweziensis.

The specimens comprise 14 new species recorded in DR Congo and 2 new species recorded in Burundi. The report also makes 4 new combinations: Coleus betonicifolius var. kasomenensis, C. esculentus var. densus, C. esculentus var. primulinus and C. parvifolius. The lectotype includes 10 names and the neotype includes 1 name.

The researchers also report 13 new synonyms. Special attention is paid to the Coleus bojeri complex. The report also makes 3 names to accommodate the wide variation pattern in Central Africa consisting of C. chevalieri, C. collinus and C. heterotrichus. Meanwhile, the endemic species of DR. Congo, Rwanda and Burundi include 15 taxa.

The genus Coleus (Lour) was first formally described by the Portuguese botanist João de Loureiro (1717-1791) in 1790 in Fl. Cochinch.: 372. The large genus includes more than 300 species, dozens of synonyms and most occur naturally in Africa, the Middle East, South Asia, Southeast Asia and Australia.

Original research

Meerts PJ, Paton AJ (2024). The genus Coleus (Lamiaceae) in Central Africa (Democratic Republic of the Congo, Rwanda, Burundi), with the description of 15 new species. PhytoKeys 246: 71-178, DOI:10.3897/phytokeys.246.129476

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