© 2017 The Linnean Society of London, Botanical Journal of the Linnean Society, 2017, 184, 457–484
457
Botanical Journal of the Linnean Society, 2017, 184, 457–484. With 8 figures.
Inclusion of Ihlenfeldtia and Odontophorus in Cheiridopsis
(Ruschioideae: Aizoaceae) and insights into generic and
subgeneric circumscription in the Conophytum clade
ROBYN F. POWELL
1,2
*, JAMES S. BOATWRIGHT
1
, CORNELIA KLAK
3
and
ANTHONY R. MAGEE
2,4
1
Department of Biodiversity and Conservation Biology, University of the Western Cape, Private Bag X17,
Bellville, Cape Town 7535, South Africa
2
Compton Herbarium, South African National Biodiversity Institute, Private Bag X7, Claremont, Cape
Town 7735, South Africa
3
Bolus Herbarium, Department of Biological Sciences, HW Pearson Building, University of Cape Town, Rhodes
Gift, 7707 Rondebosch, South Africa
4
Department of Botany and Plant Biotechnology, University of Johannesburg, P.O. Box 524, Auckland
Park, Johannesburg 2006, South Africa
Received 11 August 2016; revised 20 March 2017; accepted for publication 11 May 2017
Phylogenetic sampling in the Conophytum clade (Aizoaceae) was expanded to include a comprehensive representa-
tion of almost all species in the clade (excluding Conophytum, which was selectively sampled) for six plastid regions
(matK, rpl16, rps16, trnL-F, trnQ-rps16 and trnS-trnG). The combined phylogenetic data were analysed using maxi-
mum parsimony, maximum likelihood and Bayesian inference. The expanded sampling recovered a strongly supported
sister relationship between Cheiridopsis and Conophytum in the phylogenetic analyses. Cheiridopsis was, however,
not recovered as monophyletic, with Ihlenfeldtia and Odontophorus being embedded in it. In Cheiridopsis, three
clades were recovered, largely corresponding to the three subgenera currently recognized. Odontophorus was recov-
ered in the Cheiridopsis subgenus Odontophoroides clade and Ihlenfeldtia in the Cheiridopsis subgenus Aequifoliae
clade. Cheiridopsis is here expanded to include Ihlenfeldtia and Odontophorus, with four new combinations made
in Cheiridopsis to accommodate the latter. Three species previously classified in Cheiridopsis subgenus Aequifoliae
(C. glomerata, C. pillansii and C. purpurea) were recovered in the subgenus Odontophoroides clade, with which they
share the erect capsules with rounded tops; they are accordingly here included in this subgenus. A detailed study on
morphological characters was conducted for all the species in the Conophytum clade to aid the assessment of generic
circumscription and morphological variation in the clade. The old leaves form sheaths that enclose the emerging
leaf pairs, which was recovered as a synapomorphic character for the Conophytum–Cheiridopsis clade. Two capsule
morphologies were found across the Conophytum clade: simple capsules without covering membranes and closing
bodies and complex multilocular capsules with covering membranes and closing bodies. Leaf anatomical characters
revealed that most genera in the Conophytum clade possessed papillae on the epidermis, ranging from blunt papil-
lae to trichomes; Enarganthe, Jensenobotrya, Namaquanthus and Ruschianthus were glabrous. Pollen exine and
colpus structure were mostly uniform (tricolpate pollen with poorly defined colpi). In Namaquanthus, the exine was
extensively micro-reticulate, in Enarganthe pollen was tricolpate with well-defined colpi and in Jensenobotrya pollen
was syncolpate with multiple colpi, further separating these morphologically distinct monotypic genera. A key to the
genera of the Conophytum clade and an updated key to the subgenera of Cheiridopsis are provided. Revised generic
and subgeneric descriptions for Cheiridopsis, with appropriate nomenclatural changes, a list of recognized species,
information on species richness and distribution maps for the recircumscribed genus and subgenera are included.
ADDITIONAL KEYWORDS: Cheiridopsis subgenus Aequifoliae – Cheiridopsis subgenus Odontophoroides – leaf
anatomy – morphology – papillae – phylogeny – sheaths.
*Corresponding author. E-mail: robyn.powell.sanbi@gmail.com
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