Coleus calaminthoides (Baker) A. J. Paton, Phytokeys 129: 30. 2019. ≡ Solenostemon calaminthoides Baker in D. Oliver & auct. suc. (eds.), Fl. Trop. Afr. 5: 421. 1900. Type: Gabon, Gabon River, G. Mann s. n. (holotype K [K 001615425]). Description. Paton (2022: 44). The materials from DR. Congo differ from the materials in the rest of the range in having the hairs on the stem either retrorse or antrorse (always antrorse out of DR. Congo). Distribution. Cameroon, Equatorial Guinea, Gabon, DR. Congo. Habitat and ecology. Coastal scrub on sandy soil; 0–100 m elev. Additional specimens. DR. Congo, Côtier, Plateau de Tshikai, route Boma-Banana, 13 Apr 1960, Compère 1863 (BR); Route Boma-Banana, entre Malemba et Matamba ma Kanzi, 13 Mar 1959, J. Wagemans 2230 (BR); Mayumbe, Luki, 5 ° 34 ' 50.73 " S, 13 ° 9 ' 34.16 " E, 6 Apr 2010, S. Dessein 3222 (BR); Forêt de Moba [entre Luki et Boma], route de Boma, 5 Dec 1948, C. Donis 2233 (BR); without locality, Aug-Sep 1899, Tilman in Cabra 67 (BR). Notes. 1. The species was identified in DR. Congo for the first time by A. J. Paton in 2021; it had been hitherto misidentified as C. monostachyus. The Congolese localities represent the southernmost limit of the species’ distribution range. 2. Paton et al. (2022) consider that C. calaminthoides differs from C. monostachyus in having antrorse hairs on the stem. However, this character is variable in DR. Congo, with C. Donis 2233 having antrorse hairs, while the other specimens have retrorse hairs. 3. The specimen Tilman in Cabra 67 (BR) is close to C. calaminthoides, except for the yellow corolla; it could be a different taxon.

Published as part of Meerts, Pierre J. & Paton, Alan J., 2024, The genus Coleus (Lamiaceae) in Central Africa (Democratic Republic of the Congo, Rwanda, Burundi), with the description of 15 new species, pp. 71-178 in PhytoKeys 246 on pages 71-178, DOI: 10.3897/phytokeys.246.129476