Clivia taxonomy revisited, using DNA barcode regions

Clivia is a genus of the family Amaryllidaceae endemic to South Africa and Swaziland. Six species and one natural hybrid have been described. Some morphological traits overlap between some species causing taxonomic confusion. The core DNA barcodes (matK and rbcLa) have been analysed to evaluate their discriminatory power and to assess the current taxonomy of Clivia. Seventy-four two-locus DNA barcodes representing 4-18 specimens per species were generated. The matK region had a higher mean intraspecific variation of 0.21 compared with the 0.02 of rbcLa. The two-locus barcodes have an aligned length of 1413 base pairs. Three species, C. mirabilis, C. nobilis and C. caulescens are monophyletic in the Bayesian Inference (BI) cladogram. The remaining Clivia species (C. miniata, C. gardenii, C. robusta and their affinities) are paraphyletic. Clivia is divided into 17 haplogroups with those of C. mirabilis and C. nobilis being unique. Clivia caulescens has three haplotypes. The Clivia species from the north-eastern distribution range of the Eastern Cape and KwaZulu-Natal provinces have 11 haplogroups and no species-specific DNA barcodes. These groups have no correlation with the current taxonomical division or geographical distribution. Only 37.33% of the species can be correctly identified with the “best match” option in SpeciesIdentifier. Clivia mirabilis, C. nobilis and C. caulescens have unique DNA barcodes to identify them. Specimens from the Ngome area in KwaZulu-Natal have a unique DNA barcode, separating them from the rest of C. gardenii. A taxonomical revision is suggested.