Angraecum section Afrangraecum Summerh. Kew Bull., 13, 276 (1958).
Angraecum section Afrangraecum Summerhayes (1958: 276), typified by Angraecum reygaertii De Wildeman (1916: 190), has been established to accommodate species with long, slender, several-flowered, determinate or indeterminate inflorescences with medium to large flowers. Garay (1973: 503) accepted the section in his synopsis of the genus and recognised two groups, one with a prominent peduncle and inconspicuous bracts and a second with a short peduncle and prominent bracts. Later, Stewart et al. (2006: 93) identified two main groups within the section, the first comprising species with white/whitish flowers and a second with green/yellowish flowers. However, the most recent revisions of Angraecum failed to clarify the position of sect. Afrangraecum. Szlachetko et al. (2013) included one accession of Angraecum multinominatum Rendle (1913: 107) as the only representative of the section in their study, which resulted in misplacement and could not explain its position in the phylogenetic tree.
The recent study of Andriananjamanantsoa et al. (2016) represented the most comprehensive phylogenetic reconstruction of genus Angraecum and included all sections sensu Garay (1973) except the African members of sect. Afrangraecum. The centre of diversity of sect. Afrangraecum appears to be in Central Africa, as the majority of its species are restricted to the region, with only a few species occurring in East Africa.
Species of section Afrangraecum sensu Garay (1973) have highly diverse, even opposite morphological characters, such as resupinate and non-resupinate flowers, e.g., A. angustum (Rolfe 1898: 570) Summerhayes (1936a: 452) vs. A. affine Schlechter (1905: 19); two different types of inflorescences, determinate in A. claessensii De Wildeman (1916: 184) vs. indeterminate in A. reygaertii; different flower colours from pure white to green or orange; and diverse lip shapes, elliptic, subtrilobed, trullate etc. Species relationships within the section remain unclear, and therefore the description of new species may help to unravel the phylogenetic relationships of A. sect. Afrangraecum.
Type:
Angraecum reygaertii De Wildeman (1916
Key to the species of Angraecum section Afrangraecum:
References:
Taxonomy of Atlantic Central African orchids, 6: three new species of Angraecum sect. Afrangraecum (Orchidaceae, Angraecinae) from Gabon and São Tomé, Phytotaxa 323 (2): 143–158,2017
World Checklist of Monocotyledons. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/monocots/ 30/07/2020
