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Lachenalia (Asparagaceae; Scilloideae; Hyacintheae) is a large and morphologically diverse genus of more than 140 bulbous species endemic to southern Africa. Previous attempts to infer a well‐resolved and robustly supported phylogeny of Lachenalia using Sanger sequencing of candidate loci and/or morphological characters have been largely unsuccessful. Consequently, the current infrageneric classification is artificial, and there is a need to explore alternative avenues to produce a phylogenetic classification. In this paper, we present a novel phylogenetic hypothesis for Lachenalia inferred using maximum likelihood and coalescent‐based species tree estimation (ASTRAL) as applied to 378 hybrid‐enrichment loci. Our tree is well resolved and well supported, providing strong support for a monophyletic radiation of the genus in southern Africa and a solid foundation for a revised infrageneric classification. The well‐supported placement of L. isopetala Jacq. as sister to Lachenalia + Massonia supports the establishment of a new monotypic genus, Pseudolachenalia, to accommodate this species. Conversely, the inclusion of species previously classified as Polyxena within the Lachenalia clade supports the transfer of these species to Lachenalia. Within Lachenalia, the delimitation of subgenera and sections is complicated by the highly imbalanced character of the phylogeny and by the high levels of homoplasy shown by most morphological characters traditionally used to delimit species in this group. Nonetheless, we propose an infrageneric taxonomy comprising 10 morphologically distinct, monophyletic sections. The largest of these, L. sect. Lachenalia, is further divided into 13 more‐or‐less diagnosable, monophyletic subsections. Keys to the sections of Lachenalia, and to the subsections of L. sect. Lachenalia, are provided. [ABSTRACT FROM AUTHOR]

Recent phylogenetic hypotheses reveal that Thesium (Santalaceae) is paraphyletic with respect to Austroamericium, Chrysothesium, Kunkeliella and Thesidium, suggesting the need for generic realignment. In addition, existing subgeneric and sectional classifications of this large genus lack a phylogenetic basis, thus compromising their predictive value. Using an expanded taxon sampling and a combination of nuclear (ITS) and chloroplast (matK, rpl32‐trnL, trnL‐F) DNA sequence data, we therefore re‐assessed the phylogenetic relationships of Thesium and used these as the basis of a new subgeneric classification of the genus. Our phylogeny confirms the need to sink the four segregate genera to render Thesium monophyletic. In addition, it resolves five well‐supported major clades within Thesium that we recognize as subgenera. Within Thesium, the South African endemic subgenus Hagnothesium is sister to the Eurasian subgenus Thesium (including Kunkeliella and Mauritanica). The subgenus Psilothesium, occurring in tropical South America (formerly genus Austroamericium) and tropical Africa, is sister to the rest of the subgenera, which are all confined to South Africa. Within the latter, the subgenus Discothesium consists of subtropical and temperate species, whereas subgenus Frisea, comprising the previously recognized sections Annulata, Barbata, Frisea, Imberbia and Penicillata, is entirely of the Greater Cape Floristic Region. To facilitate identification of subgenera, we identify morphological ancestral characters and present an identification key, brief diagnoses, species assigned, distribution and ecological data. [ABSTRACT FROM AUTHOR]

The "Relhania clade" is a relatively species-poor lineage that is sister to the remaining members of the paper daisy tribe Gnaphalieae. Although the monophyly of the Relhania clade is well established, previous molecular studies are based on fairly sparse sampling. Here, we explore clade membership and generic circumscription using plastid and nuclear DNA sequence data, and near-complete species-level sampling of all putative member genera. Two subclades are recovered within the Relhania clade: (i) clade I housing the genera Alatoseta, Athrixia, Pentatrichia and Phagnalon, all monophyletic as currently circumscribed; and (ii) clade II, containing the genera Antithirixia, Comborhiza, Oedera, Oreoleyesera, Relhania and Rosenia; the annual or otherwise "short-lived" genera Leysera, Nestlera and Rhynchopsidium; as well as a subclade in which the monospecific Arrowsmithia is embedded within Macowania. A new taxonomic treatment involving 12 new combinations is proposed for the two latter genera. Only demonstrably monophyletic and diagnosable genera are recognised, involving the erection of a novel monospecific genus, Fluminaria, to house Macowania pinifolia, and the transfer of the remaining members of Macowania to Arrowsmithia. Updated descriptions and keys are provided. [ABSTRACT FROM AUTHOR]

Ifloga and Trichogyne constitute a small but biologically interesting lineage within the tribe Gnaphalieae (Asteraceae). Species are distributed mainly in the semi-arid parts of southern Africa, but there is a disjunction to the Saharo-Sindian region where three species occur. Due partly to an unusual capitulum structure, the phylogenetic position of the group has been little understood. In addition, the monophyly of the genera has not been assessed using phylogenetic methods. A species-level phylogenetic hypothesis is presented, based on one nuclear and two chloroplast DNA regions, analysed with parsimony and Bayesian methods. Ifloga+Trichogyne constitute the "Ifloga clade" that forms one of the early-diverging lineages within Gnaphalieae. These lineages constitute a basal grade with many poorly supported nodes, precluding robust hypotheses of relationships amongst the lineages. A sister lineage to the Ifloga clade could thus not be identified, although it diverges amongst taxa formerly united in subtribe Relhaniinae. Although this subtribe is now known to be non-monophyletic, members of the Ifloga clade share with former members of Relhaniinae a previously overlooked set of leaf characters. The genus Trichogyne is monophyletic, but Ifloga is paraphyletic with respect to Trichogyne. To retain generic monophyly, all species are here transferred to the genus Ifloga. Although two of the Northern-Hemisphere species were not included in the analysis, morphological characters suggest that the three species from this region are monophyletic, in which case the Saharo-Sindian distribution is the result of a single dispersal northwards from Southern Africa. A new combination and an updated key to the species are presented. [ABSTRACT FROM AUTHOR]

Of the 90-95 species included in the Rytidosperma clade of grasses (Danthonioideae: Poaceae) about 20 are native to southern Africa, most of these belonging to the genera Karroochloa, Schismus and Tribolium. Whereas morphological data identify all three genera as being monophyletic, the robustness of this pattern is compromised by high levels of homoplasy. Here we use molecular data (plastid trnL-trnF and nuclear ITS sequences) to re-evaluate phylogenetic relationships within the Rytidosperma clade, with the specific aim of testing the monophyly of the African genera. Separate parsimony analyses of the two partitions reveal low levels of incongruence, which may be attributable to incomplete lineage sorting or past hybridization. Analyses of the combined data produce well resolved, strongly supported topologies that are virtually identical, regardless of the inference method used (parsimony or Bayesian inference) or whether or not "conflict" taxa are included. Our data support the monophyly of the Rytidosperma clade (synapomorphies include a punctate-ovate hilum, a large embryo, and lodicule microhairs) as well as the monophyly of the Australasian-South American Rytidosperma s.l. However, the monophyly of Karroochloa, Schismus and Tribolium is strongly contradicted, all three genera being polyphyletic as currently defined. Although not implemented here, a minimum of five new combinations would be required to rectify this situation. Character reconstructions reveal extensive convergence in a number of morphological features, especially those previously used to define genera. We suggest that the convergent pattern of evolution displayed by these traits, most of which describe spikelet/diaspore morphology, is linked to their functionality in seed dispersal and burial, and that this has compromised their utility as phylogenetic markers. [ABSTRACT FROM AUTHOR]