A synoptic revision of the creeping herbaceous African species of Ardisia (Primulaceae or Myrsinaceae) with six new species from Cameroon and Gabon
Published 2025-11-17
Keywords
- ardisiaquinones,
- bacterial nodules,
- conservation,
- extinct species,
- Paraburkholderia
How to Cite
Copyright (c) 2025 Peng Peng, Martin Cheek

This work is licensed under a Creative Commons Attribution 4.0 International License.
Abstract
Currently 39 species of Ardisia are recognised from continental Africa, of which three (A. sadebeckiana Gilg, A. schlechteri Gilg, and A. ebo Cheek, each endemic to Cameroon and known from a single collection) are herbaceous, with creeping, horizontal, rooting herbaceous stems, the stem apex more or less ascending to up to c. 10 cm tall above the ground (decumbent). These species lack the distinctive plagiotropic (perpendicular and horizontal) aerial reproductive stems seen in most woody Ardisia species of Africa (instead sporadically producing rooting ascending stems from the horizontal stem) and have distichous leaves (not spiralled as in most species in Africa). Accordingly, they are proposed as a separate subgenus Kamardisia. Study of herbarium material revealed that six additional species exist which are described and illustrated in this paper, together with preliminary conservation assessments. These are: A. hansii (South Region, Cameroon and Belinga, Gabon), A. massaha (Belinga, Gabon), A. chaillu, A. minuta, A. waka (all Chaillu Massif, Gabon), A. ngounie (Ogooué-Maritime, Gabon). We provide a key to the identification of the nine herbaceous species, provide preliminary conservation assessments for each, and notes on shared characteristics of the African herbaceous species including the taxonomic value of leaf microcharacters (oil glands and trichomes). We also make a preliminary report on the possibility of bacterial colonisation of marginal leaf pores in some of these herbaceous species. All of the species are range restricted, the most wide-ranging with only three sites. All but one species is threatened, and almost all of those are Critically Endangered (provisional assessments). The two first published species have not been seen for more than 125 years, despite being in easily accessible, well-botanised locations, and are both feared extinct. We discuss actions to attempt to refind these species and safeguard the remainder.
References
- Anon. 1905. Scientific Notes and Views, Science, New Series. 21(536): 556 https://www.jstor.org/stable/1630357?seq=
- Beentje H. 2016. The Kew Plant Glossary: An Illustrated Dictionary of Plant Terms. Royal Botanic Gardens, Kew, London.
- Cable S, Cheek M. 1998. The Plants of Mt Cameroon, a Conservation Checklist. Royal Botanic Gardens, Kew.
- Capuron R. 1963. Le genre Ardisia Swartz (Myrsinacées) a Madagascar. Adansonia ser. 2(3): 384
- Chapman J, Chapman H. 2001. The Forests of Taraba and Adamawa States, Nigeria an Ecological Account and Plant Species Checklist. University of Canterbury: Christchurch, New Zealand. Pp. 221.
- Cheek M, Cable S. 1997. Plant Inventory for conservation management: the Kew-Earthwatch programme in Western Cameroon, 1993–96: 29–38. In Doolan S. (Ed.) African Rainforests and the Conservation of Biodiversity. Earthwatch Europe, Oxford.
- Cheek M, Cable S. 2000a. Ardisia etindensis. The IUCN Red List of Threatened Species 2000:e.T39527A10245428. https://doi.org/10.2305/IUCN.UK.2000.RLTS.T39527A10245428.en. Accessed on 11 July 2025.
- Cheek M, Cable S. 2000b. Ardisia schlechteri. The IUCN Red List of Threatened Species 2000:e.T39529A10245538. https://doi.org/10.2305/IUCN.UK.2000.RLTS.T39529A10245538.en. Accessed on 24 April 2025.
- Cheek M, Onana JM. 2024. Keetia nodulosa sp. nov. (Rubiaceae-Vanguerieae) of West-Central Africa: bacterial leaf nodulation discovered in a fourth genus and tribe of Rubiaceae. Webbia. 79(1): 31–46. https://doi.org/10.36253/jopt-15946
- Cheek M, Williams S. 1999. A Review of African Saprophytic Flowering Plants: 39–49. In: Timberlake J, Kativu S. (Eds.) African Plants. Biodiversity, Taxonomy & Uses. 15th AETFAT Congress, Harare, Zimbabwe.
- Cheek M, Xanthos M. 2012. Ardisia ebo sp. nov. (Myrsinaceae), a creeping forest subshrub of Cameroon and Gabon. Kew Bulletin. 67(2): 281. https://doi.org/10.1007/s12225-012-9362-8
- Cheek M, Cable S, Hepper FN, Ndam N, Watts J. 1996. Mapping plant biodiversity on Mt. Cameroon: 110–120. In: van der Maesen, van der Burgt, van Medenbach de Rooy (Eds.), The Biodiversity of African Plants (Proceedings XIV AETFAT Congress. Kluwer.
- Cheek M, Etuge M, Williams S. 2019. Afrothismia kupensis sp. nov. (Thismiaceae), Critically Endangered, with observations on its pollination and notes on the endemics of Mt Kupe, Cameroon. Blumea. 64: 158–164. https://doi.org/10.3767/blumea.2019.64.02.06
- Cheek M, Feika A, Lebbie A, Goyder D, Tchiengue B, Sene O, Tchouto P, van der Burgt X. 2017. A synoptic revision of Inversodicraea (Podostemaceae). Blumea. 62: 125–156. https://doi.org/10.3767/blumea.2017.62.02.07
- Cheek M, Harvey YB, Onana J-M. 2010. The Plants of Dom. Bamenda Highlands, Cameroon: A Conservation Checklist. Royal Botanic Gardens, Kew.
- Cheek M, Harvey YB, Onana J-M. 2011. The Plants of Mefou Proposed National Park. Yaoundé, Cameroon: A Conservation Checklist. Royal Botanic Gardens, Kew.
- Cheek M, Nic Lughadha E, Kirk P, Lindon H, Carretero J, Looney B, Douglas B, Haelewaters D, Gaya E, Llewellyn T, Ainsworth M, Gafforov Y, Hyde K, Crous P, Hughes M, Walker BE, Forzza RC, Wong KM, Niskanen T. 2020. New scientific discoveries: plants and fungi. Plants, People Planet. 2: 371–388. https://doi.org/10.1002/ppp3.10148
- Cheek M, Onana J-M, Pollard BJ. 2000. The Plants of Mount Oku and the Ijim Ridge, Cameroon, a Conservation Checklist. Royal Botanic Gardens, Kew.
- Cheek M, Pollard BJ, Darbyshire I, Onana JM, Wild C. 2004. The Plants of Kupe, Mwanenguba and the Bakossi Mts, Cameroon. A Conservation Checklist. Royal Botanic Gardens, Kew.
- Cheek M, Prenner G, Tchiengué B, Faden RB. 2018.Notes on the endemic plant species of the Ebo Forest, Cameroon, and the new, Critically Endangered, Palisota ebo (Commelinaceae). Plant Ecology & Evolution. 151(3): 434–441. https://doi.org/10.5091/plecevo.2018.1503
- Cheek M, Sidwell K, Sunderland T, Faruk A. 1992. A Botanical Inventory of the Mabeta-Moliwe Forest. Royal Botanic Gardens, Kew; report to Govt. Cameroon from O.D.A.
- Cheek M, Soto Gomez M, Graham SW, Rudall PJ. 2024. Afrothismiaceae (Dioscoreales), a new fully mycoheterotrophic family endemic to tropical Africa. Kew Bulletin. 1–19. https://doi.org/10.1007/s12225-023-10124-w
- Cheek M, Tsukaya H, Rudall PJ, Suetsugu K. 2018. Taxonomic monograph of Oxygyne (Thismiaceae), rare achlorophyllous mycoheterotrophs with strongly disjunct distribution. PeerJ. 6: e4828. https://doi.org/10.7717/peerj.4828
- Darbyshire I, Anderson S, Asatryan A, Byfield A, Cheek M, Clubbe C, Ghrabi Z, Harris T, Heatubun CD, Kalema J, Magassouba S, McCarthy B, Milliken W, Montmollin B de, Nic Lughadha E, Onana JM, Saıdou D, Sarbu A, Shrestha K, Radford EA. 2017. Important Plant Areas: revised selection criteria for a global approach to plant conservation. Biodiversity Conservation. 26: 1767–1800. https://doi.org/10.1007/s10531-017-1336-6
- Davies NMJ, Drinkell C, Utteridge TMA. 2023. The Herbarium Handbook. Kew Publishing
- de Wit HCD. 1958. Revision of Afrardisia Mez (Myrsinaceae). Blumea. 4 (supplement): 242–262.
- Dzoyem JP, Ndontsa BL, Santosh KG, Inshad A, Khan ASK, Vishwakarma RA, Tane P. 2014. Antiproliferative and antimicrobial activities of alkylbenzoquinone derivatives from Ardisia kivuensis. Pharmaceutical Biology. 52(3): 392–397, https://doi.org/10.3109/13880209.2013.837076
- GBIF. continuously updated. Global Biodiversity Information Facility [online]. Available from https://www.gbif.org/occurrence/map?taxon_key=3169458&occurrence_status=present. Aaccessed 9 Feb. 2021.
- Ghogue J.-P. 2010. Ledermanniella batangensis. The IUCN Red List of Threatened Species 2010: e.T185525A8428951. https://doi.org/10.2305/IUCN.UK.2010-3.RLTS.T185525A8428951.en. Accessed on 14 July 2025.
- Gilg E. 1902. Myrsinaceae africanae. Botanische Jahrbücher fur Systematik, Pflanzengeschichte und Pflanzengeographie. 30: 95–101. https://www.biodiversitylibrary.org/page/211309#page/100/mode/1up
- Gilg E, Schellenberg G. 1913. Myrsinaceae africanae. II.Botanische Jahrbücher fur Systematik, Pflanzengeschichte und Pflanzengeographie. 48: 512–525 https://www.biodiversitylibrary.org/item/136883#page/552/mode/1up
- Good RD. 1927. Myrsinaceae. Journal of Botany, British and foreign. 65(supplement): 69.
- Gosline G, Cheek M, Onana JM, Ngansop Tchatchouang E, van der Burgt XM, MacKinnon L, Dagallier LMJ. 2022. Uvariopsis dicaprio (Annonaceae) a new tree species with notes on its pollination biology, and the Critically Endangered narrowly endemic plant species of the Ebo Forest, Cameroon. PeerJ. Jan 6; 9:e12614. https://doi.org/10.7717/peerj.12614
- Halliday P. 1984 Myrsinaceae. In: Polhill RM (Ed.) ,Flora of Tropical East Africa: 16–19. Balkema, Rotterdam.
- Harvey YB, Pollard BJ, Darbyshire I, Onana J-M, Cheek M. 2004. The Plants of Bali Ngemba Forest Reserve. Cameroon: A Conservation Checklist. Royal Botanic Gardens, Kew.
- Harvey YB, Tchiengue B, Cheek M. 2010. The Plants of the Lebialem Highlands, a Conservation Checklist. Royal Botanic Gardens, Kew.
- Hepper FN. 1963. Flora of West Tropical Africa 2: 31. Crown Agents, London.
- IPNI. continuously updated. The International Plant Names Index. http://ipni.org/ (accessed: 07/2023).
- IUCN. 2012. IUCN Red List Categories and Criteria: Version 3.1. Second edition.–Gland, Switzerland and Cambridge, UK: IUCN. Available from: http://www.iucnredlist.org/. Accessed on April 2025.
- Julius A, Utteridge TMA. 2012. Revision of Ardisia subgenus Bladhia in Peninsular Malaysia; studies in Malaysian Myrsinaceae I. Kew Bulletin. 67(3): 379–388. https://doi.org/10.1007/s12225-012-9374-4
- Julius A, Utteridge TMA. 2021. Ardisia recurvisepala (Primulaceae-Myrsinoideae), a new species from Peninsular Malaysia. Phytotaxa. 480(1): 79-84. https://doi.org/10.11646/phytotaxa.480.1.7
- Julius A, Utteridge TMA. 2022. Ardisia whitmorei (Primulaceae-Myrsinoideae), a new species from Peninsular Malaysia. PhytoKeys. 204: 35–41. https://doi.org/10.3897/phytokeys.204.86647
- Julius A, Kajita T, Utteridge TMA. 2017. Ardisia gasingoides (Primulaceae-Myrsinoideae), a new species from southern Peninsular Malaysia. Phytotaxa. 291(4): 281–286. https://doi.org/10.11646/phytotaxa.291.4.5
- Julius A, Gutiérrez-Ortega JS, Sabran S, Tagane S, Naiki A, Darnaedi, D, Aung M, Dang S, Nguyen N, Binh H, Watano Y. 2021. Phylogenetic relationship of tropical Asian Ardisia and relatives (Primulaceae) shows non-monophyly of recognized genera and subgenera. Shokubutsu Kenkyu Zasshi. 93: 149–165.
- Julius A, Siti-Munirah MY, Utteridge TMA. 2023. Ardisia recurvipetala (Primulaceae-Myrsinoideae), a new species from northern Peninsular Malaysia. PhytoKeys. 232: 89–98. https://doi.org/10.3897/phytokeys.232.103649
- Kitajima K, Fox AM, Sato T, Nagamatsu D. 2006. Cultivar selection prior to introduction may increase invasiveness: evidence from Ardisia crenata. Biological Invasions. 8:1471–1482. https://doi.org/10.1007/s10530-005-5839-9
- Larsen K, Hu CM. 1995. Reduction of Tetrardisia to Ardisia. Nordic Journal of Botany. 15: 161–162. https://doi.org/10.1111/j.1756-1051.1995.tb00134.x
- Larson DA, Chanderbali AS, Maurin O, Gonçalves DJ, Dick CW, Soltis DE, Utteridge TM. 2023. The phylogeny and global biogeography of Primulaceae based on high-throughput DNA sequence data. Molecular Phylogenetics and Evolution. 182: 107702. https://doi.org/10.1016/j.ympev.2023.107702
- Lemaire B, Vandamme P, Merckx V, Smets E, Dessein S. 2011. Bacterial leaf symbiosis in angiosperms: host specificity without co-speciation. PLoS One. 6(9): e24430. https://doi.org/10.1371/journal.pone.0024430
- Lersten NR, Horner HT. 1976. Bacterial leaf nodule symbiosis in angiosperms with emphasis on Rubiaceae and Myrsinaceae. Botanical Review. 42: 145–214 https://doi.org/10.1007/BF02860721
- Liu B, Liu R, Liu Q, Ashby Jr CR, Zhang, H, Chen ZS. 2022. The ethnomedicinal and functional uses, phytochemical and pharmacology of compounds from Ardisia species: an updated review. Medicinal Research Reviews. 42(5): 1888–1929. https://doi.org/10.1002/med.21894
- Lockwood H, Tchatchouang EN. 2025. Begonia ebo sp. nov. (Sect. Filicibegonia-Begoniaceae), endangered in Ebo, a highly threatened forest in Littoral Region, Cameroon. Webbia. 80(1): 77–87. https://doi.org/10.36253/jopt-17739
- Lovell R, Cheek M. 2020. Ardisia ebo. The IUCN Red List of Threatened Species 2020: e.T172490315A172490333. https://doi.org/10.2305/IUCN.UK.2020-3.RLTS.T172490315A172490333.en. Accessed on 13 April 2025.
- Magtoto LM, Tamayo MN, Udasco LC, Bustamante RAA. 2021. Ardisia kalimbahin (Primulaceae, Myrsinoideae), a new species from the Philippines. Phytotaxa. 525: 4 doi:10.11646/phytotaxa.525.4.4
- Mao SZ, Hu CM. 2013. Ardisia rubricaulis sp. nov. (Primulaceae) from Guangxi, China. Phytotaxa. 138(1): 39–42. https://doi.org/10.11646/phytotaxa.138.1.5
- Maisels FM, Cheek M, Wild C. 2000. Rare plants on Mt Oku summit, Cameroon. Oryx. 34: 136–140. https://doi.org/10.1017/s0030605300031057
- Mez, C. 1902. Myrsinaceae. In: Engler A. (Ed.), Das Pflanzenreich, Heft 9 (IV. Fam. 236). Verlag von Wilhelm Engelmann, Leipzig, 437 pp.
- Murphy B, Onana JM, van der Burgt XM, Tchatchouang Ngansop E, Williams J, Tchiengué B, Cheek M. 2023. Important Plant Areas of Cameroon. Royal Botanic Gardens, Kew.
- Nuraliev MS, Kuznetsov AN, Kuznetsova SP, & Hu CM. 2021. Ardisia patentiradiosa (Primulaceae), a new species from southern Vietnam. Phytotaxa. 522(1): https://doi.org/10.11646/phytotaxa.522.1.7
- Oliver D. 1877. Flora of Tropical Africa 3: 495. L. Reeve and Company, London.
- Onana J-M. 2011. The Vascular Plants of Cameroon. A Taxonomic Checklist with IUCN Assessments. Flore Du Cameroun 39. Ministry of Scientific Research and Innovation, Yaoundé, Cameroon.
- Onana JM, Cheek M. 2011. Red Data Book of the Flowering Plants of Cameroon, IUCN Global Assessments. Royal Botanic Gardens, Kew.
- Perrier de la Bâthie H. 1952. Pharmacopée malgache. Mémoires de l’Institut Scientifique de Madagascar. Série B. Biologie Végetale 4:207.
- POWO continuously updated. The Plants of the World online [online]. Available from http://www.plantsoftheworldonline.org/. Accessed on 29 Jan. 2025.
- Pinto-Carbó M, Gademann K, Eberl L, Carlier A. 2018. Leaf nodule symbiosis: function and transmission of obligate bacterial endophytes. Current opinion in plant biology. 44: 23–31. https://doi.org/10.1016/j.pbi.2018.01.001
- Quan D-L, Tan YH. 2024. Ardisia chimingiana (Primulaceae), a New Species from Yunnan, China. Annales Botanici Fennici. 61(1): 7–15 https://doi.org/10.5735/085.061.0102
- Simpson, W. (continuously updated). Ardisia crenata, coral berry in: https://www.fdacs.gov/Agriculture-Industry/Pests-and-Diseases/Plant-Pests-and-Diseases/Noxious-Weeds/Ardisia-crenata-Coral-Ardisia . Accessed July 2025.
- Sosef MSM, Wieringa JJ, Jongkind CCH, Achoundong G, Azizet Issembé Y, Bedigian D, Van Den Berg RG, Breteler FJ, Cheek M, Degreef J. 2006. Check-list des plantes vasculaires du Gabon. Scripta Botanica Belgica 35: 1-435. National Botanic Garden of Belgium.
- Ståhl B, Anderberg AA. 2004. Myrsinaceae. In: Kubitzki K. (Ed.), The Families and Genera of Vascular Plants 6: 266–281. Springer, Berlin.
- Stone RD, Tchiengué B, Cheek M. 2024. The endemic plant species of Ebo Forest, Littoral Region, Cameroon with a new Critically Endangered cloud forest shrub, Memecylon ebo (Melastomataceae-Olisbeoideae). Kew Bulletin. 79: 867–879. https://doi.org/10.1007/s12225-024-10223-2
- Swartz O. 1788. Nova Genera & Species Plantarum seu Prodromus descriptionum Vegetabilium, maximam partem incognitorum quae sub itinere in Indiam Occidentalem annis 1783–87. Acad. M. Swederi, Stockholm. https://doi.org/10.5962/bhl.title.4400
- Taton S. 1979. Contribution à l’étude du genre Ardisia Sw. (Myrsinaceae) en Afrique tropicale. Bulletin du Jardin Botanique National de Belgique. 49(1–2): 91–114. https://doi.org/10.2307/3667819
- Taton S. 1980. Myrsinaceae. Flore d’Afrique Centrale: 12–29, National Botanic Garden, Meise.
- Taton S, Lejoly J. 1980. Une espèce nouvelle d’ Ardisia (Myrsinaceae) du Zaïre. Bulletin du Jardin Botanique National de Belgique. 50(1–2): 463. https://doi.org/10.2307/3667783
- Thiers B. 2025. (continuously updated). Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. [continuously updated].–Available from: http://sweetgum.nybg.org/ih/. Accessed on Feb. 2023.
- Turland NJ, Wiersema JH, Barrie FR, Greuter W, Hawksworth DL, Herendeen PS, Knapp S, Kusber W-H, Li D-Z, Marhold K, May TW, McNeill J, Monro AM, Prado J, Price MJ, Smith GF. (Eds.) 2018. International Code of Nomenclature for algae, fungi, and plants (Shenzhen Code) adopted by the Nineteenth International Botanical Congress Shenzhen, China, July 2017. Regnum Vegetabile. 159. Glashütten: Koeltz Botanical Books.
- Tzinieris S. 2014. Bidding for untapped Gabon iron ore reserve, world’s largest, could spark mining sector. War Studies. https://kclpure.kcl.ac.uk/portal/en/publications/bidding-for-untapped-gabon-iron-ore-reserve-worlds-largest-could-. Accessed on April 2025.
- Wildeman ED. 1925. Plantae Bequaertianae Etudes sur les Récoltes Botaniques du Dr. J. Bequaert Chargé de Missions au Congo Belge (1913–1915). 3: 216, Lechevalier, Paris.
- Yang CJ, Hu JM. 2018. Bacterial Leaf Nodule Symbiosis in Flowering Plants, Symbiosis. IntechOpen. https://www.intechopen.com/chapters/58848
