Phytotaxa 87 (3): 50–60 (2013) www.mapress.com/ phytotaxa / Copyright © 2013 Magnolia Press Article ISSN 1179-3155 (print edition) PHYTOTAXA ISSN 1179-3163 (online edition) http://dx.doi.org/10.11646/phytotaxa.87.3.3 Trimelopter craibii (Hyacinthaceae, Ornithogaloideae), a new species from the North West Province of South Africa MARIO MARTÍNEZ-AZORÍN1, MANUEL B. CRESPO1 & ANTHONY P. DOLD2 1 CIBIO (Instituto Universitario de la Biodiversidad), Universidad de Alicante, P. O. Box 99, E-03080 Alicante, Spain. E-mail: mmartinez@ua.es 2 Selmar Schonland Herbarium, Department of Botany, Rhodes University, Grahamstown 6140, South Africa. Abstract The genus Trimelopter has been recently reinstated to include Ornithogalum unifolium and other closely related species from Southern Africa, comprising up to 10 species. Within the context of a revision of Trimelopter, a new species, T. craibii, is here formally described to name plants discovered by the late Charles Craib in the North West Province of South Africa. This taxon is closely related to T. dyeri and T. unifolium, but it can be clearly differentiated by floral and vegetative characters. Data on morphology, ecology, and distribution are reported for this new species, and affinities and divergences with other closely related taxa are also discussed. The new combination T. unifolium var. vestitum is also proposed. Key words: Asparagaceae, distribution, ecology, Hyacintheae, Scilloideae, taxonomy, Trimelopter unifolium var. vestitum Introduction The family Hyacinthaceae includes about 1000 species of bulbous plants which are mainly distributed throughout Europe, Africa and south-west Asia, with a single small genus in South America (APG 2003). Alternatively, Hyacinthaceae is treated as subfamily Scilloideae of Asparagaceae, and the subfamilies above are then treated as tribes Hyacintheae, Ornithogaleae, Oziroëeae and Urgineeae (e.g. APG 2009, Chase et al. 2009). Generic circumscription within Hyacinthaceae subfam. Ornithogaloideae has been a matter of controversy during the last couple of decades. The latest comprehensive study in the group (cf. MartínezAzorín et al. 2011) demonstrated the existence of up to 19 monophyletic genera which are characterized by a clear syndrome of morphological characters, making genus concepts intuitive, homogeneous in floral morphology, and therefore easy to define and to work with. The genus Trimelopter Rafinesque (1837: 24) currently includes 10 species and is characterized by the presence of a single, elliptic to narrowly oblong leaf (exceptionally two or three leaves), usually flattened against the ground. The ovaries have two usually prominent longitudinal dorsal keels in each carpel and the seeds are unequally compressed or semi-discoid (cf. Dyer 1931, Leighton 1944, Obermeyer 1978, MartínezAzorín et al. 2011). The peculiar morphology of these plants allowed various authors to treat them at different taxonomic ranks. Rafinesque (1837) described the genus Trimelopter, including a single species, Trimelopter fuscatum (Jacquin 1795: 19) Rafinesque (1837: 24) (= Ornithogalum fuscatum Jacq.), which is currently regarded as a synonym of T. unifolium (Retzius 1781: 17) Martínez-Azorín et al. (2011: 26) (= O. unifolium Retz.). The genus Ardernia Salisbury (1866: 35) is also based on O. fuscatum and it is therefore to be considered 50 Accepted by Lorenzo Peruzzi: 26 Feb. 2013; published online in PDF: 15 Mar. 2013