Plant Ecology and Evolution 152(3): 546-553, doi: 10.5091/plecevo.2019.1595
Justicia gigantophylla (Acanthaceae), an endangered litter-gathering species from southern Cameroon
expand article infoHarry J. Smith, Con Moran§, Olivier Lachenaud|, Iain Darbyshire
‡ Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, United Kingdom§ School of Medicine, College of Medicine and Health, University College Cork, Ireland| Botanic Garden Meise, Nieuwelaan 38, 1860 Meise, Belgium
Open Access

Background and aims – The taxonomic status of Duvernoia gigantophylla Lindau from southern Cameroon is considered in relation to the wider Justicia extensa-laxa complex of tropical Africa. Its unusual litter-gathering habit (currently unique in Acanthaceae) is also discussed.

Methods – This study was based on normal practices of herbarium taxonomy and morphological analysis. All relevant protocols were followed in the production of the conservation assessment and selection of the lectotype.

Key results – A new combination Justicia gigantophylla (Lindau) H.J.Sm. & C.Moran is proposed for this narrowly endemic and endangered species, which is re-instated, with a new description and conservation assessment. A basic key to the wider J. extensa-laxa complex is presented. Justicia gigantophylla is assessed as Endangered (EN B1ab(iii)+2ab(iii)) according to the 2012 criteria of IUCN and a new lectotype is also designated.

Cameroon, Acanthaceae, Justicia, litter-gathering, species complex, conservation


  • African Plant Database (2018, continuously updated) African Plant Database (version 3.4.0). Conservatoire et Jardin botaniques de la Ville de Genève and South African National Biodiversity Institute, Pretoria, Available at [accessed 1 Oct. 2018].
  • Bachman S., Moat J., Hill A.W., de la Torre J., Scott B. (2011) Supporting red list threat assessments with GeoCAT: geospatial conservation assessment tool. Zookeys 150: 117–126.
  • Cheek M., Pollard B.J., Darbyshire I., Onana J.-M. (2004) Plants of Kupe, Mwanenguba and the Bakossi Mountains, Cameroon: a conservation checklist. 226. Royal Botanic Gardens, Kew.
  • Cheek M., Horwath A., Haynes D. (2008) Psychotria kupensis (Rubiaceae) a new dwarf, litter-gathering species from western Cameroon. Kew Bulletin 63(2): 243–246.
  • Burkill H., Clarke C.B. (1900) Acanthaceae. In: Oliver D. (ed.) Flora of Tropical Africa vol. 5: 1–262. Royal Botanic Gardens, Kew.
  • Burkill H. (1985) The Useful Plants of West Tropical Africa, vol. 1, Families A–D. 2nd edition: 16–18. Royal Botanic Gardens, Kew.
  • Darbyshire I., Vollesen K., Kelbessa E. (2010) Acanthaceae (Part 2). In: Beentje H. (ed.) Flora of Tropical East Africa. Royal Botanic Gardens, Kew.
  • Darbyshire I., Vollesen K., Ensermu Kelbessa (2015) Acanthaceae (part II). In: Timberlake J.R., Martins E.S. (eds) Flora Zambesiaca vol. 8, pt. 6. Royal Botanic Gardens, Kew.
  • Graham V.A.W. (1988) Delimitation and infra-generic classification of Justicia (Acanthaceae). Kew Bulletin 43(4): 551–624.
  • Hawthorne W.D. (2013) Six new Pavetta (Rubiaceae), including three ‘litter-bin’ species from the evergreen forests of Western Africa. Kew Bulletin 68(4): 559–577.
  • Heine H. (1963) Acanthaceae. In: Hutchinson J., Dalziel J.M., Keay R.W.J., Hepper N. (eds.) Flora of West Tropical Africa vol. 2(2): 391–432. Royal Botanic Gardens, Kew.
  • Heine H. (1966) Acanthacées. In: Aubréville A. (ed.) Flore du Gabon vol. 13. Paris, Muséum national d’Histoire naturelle.
  • IPNI (continuously updated) The International Plant Names Index. Available at [accessed 5 Jul. 2018].
  • IUCN (2012) IUCN red list categories: Version 3.1. 2nd edition. IUCN Species Survival Commission, Gland, Switzerland and Cambridge, U.K., IUCN.
  • Kiel C.A., Daniel T.F., Darbyshire I., McDade L.A. (2017) Unraveling relationships in the morphologically diverse and taxonomically challenging “justicioid” lineage (Acanthaceae: Justicieae). Taxon 66(3): 645–674.
  • Kiel C.A., Daniel T.F., McDade L.A. (2018) Phylogenetics of New World ‘justicioids’ (Justicieae: Acanthaceae): major lineages, morphological patterns, and widespread incongruence with classification. Systematic Botany 43(2): 459–484.
  • Klopper R.R., Chatelain C., Bänninger V., Habashi C., Steyn H.M., de Wet B.C., Arnold, T.H., Gautier L., Smith G.E., Spichiger R. (2006) Checklist of the flowering plants of sub-Saharan Africa. An index of accepted names and synonyms. South African Botanical Diversity Network Report No. 42, SABONET, Pretoria.
  • Lachenaud O., Jongkind C. (2013) New and little-known Psychotria (Rubiaceae) from West Africa, and notes on litter-gathering angiosperms. Plant Ecology and Evolution 146(2): 219–233.
  • Lebrun J.-P., Stork A.L. (1997) Enumération des plantes à fleurs d’Afrique tropicale. Vol. 4. Gamopetales: Clethraceae à Lamiaceae. Geneva, Conservatoire et Jardin Botaniques de la Ville de Genève.
  • Lindau G. (1913) Acanthaceae africanae. IX. Botanische Jahrbücher fur Systematik, Pflanzengeschichte und Pflanzengeographie 49(3): 398–409.
  • Manning J.C., Getliffe-Norris F.M. (1995) Acanthaceae, Fascicle 1: Justiciinae: Duvernoia. In: Baden C., Balkwill K., Getliffe Norris F.M., Immelman K.L., Manning J.C., Munday J. (eds)Flora of Southern Africa vol. 30(3): 15–17. Pretoria, National Botanical Institute.
  • Manning J.C., Goldblatt P. (2014) Nomenclatural adjustments in African plants 1. 1. Synopsis of the genus Justicia L. (Acanthaceae) in southern Africa, with eight new combinations for species of Adhatoda Miller and Monechma Hochst. Bothalia 44(1): 42–47.
  • Turland N. J., Wiersema J. H., Barrie F. R., Greuter, W., Hawksworth D. L., Herendeen P. S., Knapp S., Kusber W.-H., Li D.-Z., Marhold K., May T. W., McNeill J., Monro A. M., Prado J., Price M. J., Smith G. F. (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.
  • Onana J.-M. (2011) The Vascular Plants of Cameroon, a Taxonomic Checklist with IUCN Assessments: 195. Yaoundé, IRAD-National Herbarium of Cameroon.
  • Onana J.-M. (2013) Synopsis des espèces végétales vasculaires endémiques et rares du Cameroun: 279. Check-liste pour la gestion durable et la conservation de la biodiversité. Flore du Cameroun 40. Yaoundé, Ministry of Scientific Research and Innovation.
  • Shorthouse D.P. (2010) SimpleMappr, an online tool to produce publication-quality point maps. Available at [accessed 5 Jul. 2018].
  • Smith H.J. (in press) Justicia gigantophylla. The IUCN Red List of Threatened Species.
  • Thiers B. (continuously updated) Index Herbariorum: A global directory of public herbaria and associated staff. New York Botanical Garden’s Virtual Herbarium. Available from: [accessed: 5 Jul. 2018].
  • White F. (1983) The vegetation of Africa. A descriptive memoir to accompany the UNESCO/AETFAT/UNSO Vegetation Map of Africa. Paris, UNESCO.
  • Zona S., Christenhusz M.J.M. (2015) Litter‐trapping plants: filter‐feeders of the plant kingdom. Botanical Journal of the Linnaean Society 179(4): 554–586.