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Ensuring that genera are monophyletic should result in a stable classification that better reflects evolutionary history, and which can serve as a framework for answering broader scientific questions. It is also important that species can be assigned to genera easily and unambiguously so as to remove barriers to identification and species discovery. Pilea, with 933 published names and likely more than 700 spp. is the largest genus within the Urticaceae and was last monographed in 1869. Whilst the monophyly of the genus has been proposed by previous authors, this has been based on incomplete taxon sampling that has failed to resolve the position of key taxa. We aimed to generate a robust phylogeny for Pileaand allied genera that could test the monophyly of the genus and provide a framework for a taxonomic revision of this species‐rich yet poorly studied genus. To do so, we sought to sample taxa encompassing previous infrageneric classifications and species with anomalous inflorescences or flower morphology and to use the resulting phylogeny to evaluate the delimitation of Pileaand to establish an infrageneric classification. In addition, we included a representative of the Polynesian genus Haroldiella, which, morphologically, seemed indistinguishable from Pilea. Using two plastid and one nuclear region, we constructed phylogenies using Bayesian inference, maximum likelihood and maximum parsimony approaches. We used our BI phylogeny to evaluate the informativeness of 22 morphological characters and used both to delimit monophyletic groups and infrageneric sections. Our results recovered Pileaas paraphyletic, a consequence of the recovery of a monophyletic clade comprising Lecanthusand Pileasect. Achudemiaand sect. Smithiella, neither of which had been adequately sampled in previous studies. We also recovered Pileaas paraphyletic with respect to Haroldiella. Pilea(including Haroldiella) was recovered as sister to the clade comprising Lecanthusand Pileasect. Achudemiaand sect. Smithiella. We identified isomery between male and female flowers, flower part number, male sepal arrangement and achene ornamentation as being phylogenetically informative characters that can be used to distinguish Achudemia(Pileasect. Achudemiaand sect. Smithiella) from Pilea. We also identified a trend of decreasing merism and fruit size, correlated with an increase in species‐richness across the phylogeny which our results suggest may indicate a shift in pollen and fruit dispersal, pollen dispersal becoming more kinetic and fruit dispersal less reliant on animals. On the basis of our evaluation of both morphological characters and phylogenetic relationships we propose a new infrageneric classification for the genus comprising eight sections, five of which we propose for the first time here: Pileasect. Angulatae, sect. Plataniflorae, sect. Tetraphyllae, sect. Trimerisand sect. Verrucosae.

Asphodelaceae subfam. Alooideae (Asparagales) currently comprises five genera, four of which are endemic to southern Africa. Despite their importance in commercial horticulture the evolutionary relationships among the genera are still incompletely understood. This study examines phylogenetic relationships in the subfamily using an expanded molecular sequence dataset from three plastid regions (matK, rbcLa, trnH–psbA) and the first subunit of the nuclear ribosomal internal transcribed spacer (ITS1). Sequence data were analysed using maximum parsimony and Bayesian statistics, and selected morphological traits were mapped onto the molecular phylogeny. Haworthia is confirmed as being polyphyletic, comprising three main clades that largely correlate with current subgeneric circumscriptions. Astroloba and Gasteria are evidently each monophyletic and sister respectively to Astroloba and H. subg. Robustipedunculares. Chortolirion is shown to be deeply nested within Aloe and is formally included in that genus. Aloe itself is clearly polyphyletic, with the dwarf species A. aristata allied to Haworthia subg. Robustipedunculares. The taxonomic implications of these findings are examined but branch support at critical lower nodes is insufficient at this stage to justify implementing major taxonomic changes.