Eremiolirion, a new genus of southern African Tecophilaeaceae, and taxonomic notes on Cyanella alba

Abstract

The generic affiliation of Cyanella amboensis Schinz has been uncertain since the species was excluded from the genus Cyanella L. in 1991. The species has two leaves, a divaricately branching inflorescence, ebracteolate pedicels, and actinomorphic flowers with monomorphic anthers. It is endemic to the western parts of central and northern Namibia. Other species of Cyanella have several leaves, racemose inflorescences, bracteolate pedicels, zygomorphic flowers with dimorphic anthers, and are endemic or near-endemic to the winter rainfall region in southwestern South Africa and southern Namibia. These differences are consistent with the recognition of the species as a distinct genus within the family. Phylogenetic analysis of plastid DNA sequences indicates that C. amboensis Schinz is sister to the other species of Cyanella, a relationship that also supports its independent generic status. The monotypic genus Eremiolirion is accordingly erected to accommodate the species. Minor differences in flower colour and vegetative morphology in Cyanella alba L.f. are shown to correlate with the three disjunct groups of populations in which the species occurs, and these populations are recognized at the level of subspecies.