Abstract
As a result of ongoing studies of the Rubiaceae of Gabon, the new species Colletoecema gabonensis is here described and illustrated. It is endemic to Gabon, where it is the only species of the genus, and is so far only known from three collections from the Ogooué-Lolo and Ngounié provinces. The new species is morphologically intermediate between its two congeners, C. dewevrei (from Cameroon, Central African Republic, Republic of the Congo, DR Congo, and Angola) and C. magna (endemic to Cameroon). The new species agrees with C. dewevrei in having flowers with exserted anthers and style, but differs in its sessile flowers and fruits. In the latter characters, it resembles C. magna, from which it can be separated by its smaller fruits and leaves, and by its different floral morphology. An IUCN conservation assessment has been made and the species is provisionally assessed as Vulnerable, based on its restricted area of occupancy and the small number of known locations.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
Literature Cited
Breteler, F. J. 2010. Revision of the African genus Anthonotha (Leguminosae, Caesalpinioideae). Plant Ecology and Evolution 143: 70–99.
Callmander, M. W., G. E. Schatz & P. P. Lowry. 2005. IUCN Red List assessment and the Global Strategy for Plant Conservation: taxonomists must act now. Taxon 54: 1047–1050.
Dauby, G., I. Parmentier & T. Stévart. 2008. A new species of Afrothismia (Burmanniaceae) from Gabon. Nordic Journal of Botany 25: 268–271.
De Wildeman, E. 1904. Plectronia dewevrei. Annales du Museé du Congo (Belge), Botanique, série 5, 1: 203.
Hallé, N. 1966. Rubiacées (1re partie). In: A. Aubréville (ed.) Flore du Gabon no. 12, pp. 278. Muséum national d'Histoire naturelle, Paris.
———. 1972. Rubiacées (2e partie). In: A. Aubréville & J.-F. Leroy (eds.) Flore du Gabon n° 17, pp. 335. Muséum national d'Histoire naturelle, Paris.
IUCN. 2001. IUCN Red List Categories and Criteria: Version 3.1. IUCN Species Survival Commission. Gland, Switzerland and Cambridge, U.K.
Ntore, S., O. Lachenaud, S. Janssens & S. Dessein. 2010. Four new Pauridiantha species (Rubiaceae) reflect the richness of Gabon’s rainforests. Belgian Journal of Botany 142: 177–193.
Petit, E. 1963. Rubiaceae Africanae X. Colletoecema, genre nouveau de Rubiaceae d’Afrique. Bulletin du Jardin botanique de l’État à Bruxelles 33: 375–380.
Piesschaert, F., L. Anderson, S. Jansen, S. Dessein, E. Robbrecht & E. Smets. 2000 Searching for the taxonomic position of the African Colletoecema (Rubiaceae): morphology and anatomy compared to an rps16-intron analysis of the Rubioideae. Canadian Journal of Botany 78: 288–304.
Robbrecht, E. & J.-F. Manen. 2006. The major evolutionary lineages of the coffee family (Rubiaceae, angiosperms). combined analysis (nDNA and cpDNA) to infer the position of Coptosapelta and Luculia, and supertree construction based on rbcL, rps16, trnL-trnF and atpB-rbcL data. A new classification in two subfamilies, Cinchonoideae and Rubioideae. Systematics and Geography of Plants 76: 85–146.
Sonké, B., S. Dessein, H. Taedoumg, I. Groeninckx & E. Robbrecht. 2008. A new species of Colletoecema (Rubiaceae) from southern Cameroun with a discussion of relationships among basal Rubioideae. Blumea 53: 533–547.
Sosef, M. S. M., J. J. Wieringa, C. C. H. Jongkind, G. Achoundong, Y. Azizet Issembé, D. Bedigian, R. G. van den Berg, F. J. Breteler, M. Cheek, J. Degreef, R. B. Faden, P. Goldblatt, L. J. G. van der Maesen, L. Ngok Banak, R. Niangadouma, T. Nzabi, B. Nziengui, Z. S. Rogers, T. Stévart, J. L. C. H. van Valkenburg, G. Walters & J. J. F. E. de Wilde. 2006. Check-list of Gabonese vascular plants. Scripta Botanica Belgica 35: 1–438.
White, F. 1979. The Guineo-Congolian Region and its relationship to other phytochoria. Bulletin du Jardin botanique national de Belgique 49: 11–55.
Acknowledgments
The herbarium curators of Paris (P) and Wageningen (WAG) are thanked for sending specimens on loan. We are grateful to Steven Darwin and an anonymous reviewer for their valuable comments, and to Antonio Fernandez for preparing the botanical drawing. The second author is a research fellow of the F.R.S.-F.N.R.S. (Belgian National Fund for Scientific Research).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Dessein, S., Lachenaud, O. & Sonké, B. Colletoecema gabonensis, a third species of an unusual African genus of Rubiaceae. Brittonia 63, 215–219 (2011). https://doi.org/10.1007/s12228-010-9153-1
Published:
Issue Date:
DOI: https://doi.org/10.1007/s12228-010-9153-1