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—We present a taxonomic revision of Dactylaena and Haptocarpum as part of a series of generic revisions and delimitation of Neotropical Cleomaceae. Two new species are described, Dactylaena boliviensis and D. zmarztyae, one new combination is made, D. monandra, four lectotypes are designated in Dactylaena, and a key to all species is presented. This is the first comprehensive revision of the now seven recognized species of Dactylaena and provides needed clarification of species boundaries, distributions, and diversity. Haptocarpum is maintained as a monotypic genus.

—Tarenaya longicarpa, commonly known as “mussambê,” is a new species from South America. Iltis previously recognized it as a subspecies of Cleome spinosa Jacq. but never published the name. Molecular phylogenetic studies have confirmed this taxon as a distinct lineage from T. spinosa. In addition, the results of a revision of Tarenaya, now underway, corroborate the separation of T. longicarpa from T. spinosa s. s.

Novel molecular data and morphological studies have provided support for the segregation of numerous genera from Cleome s. l. (Cleomaceae). Corynandra has been proposed as a segregate genus including Indian and Australian species based on floral and seed morphology. Contrasting seed coat micro-morphology between Indian and Australian species included in Corynandra raised questions over the monophyly of that genus concept. Relationships among the Indian and Australian species remain unclear due to limited sampling in previous molecular analyses. We expanded the sampling of taxa from India and Australia in order to clarify relationships between these species and the circumscription of Corynandra. Comprehensive sampling of Indian and Australian species formed three well-supported clades based on analyses of molecular sequence data and we conclude that Corynandra is not related to the Australian species. The genus Arivela Raf. is reinstated for the majority of Australian species. The new genus Areocleome is described to accommodate the unusual Australian C4 species Cleome oxalidea. The following new combinations are made: Areocleome oxalidea, Arivela arenitensis, Arivela bundeica, Arivela cleomoides, Arivela insolata, Arivela kenneallyi, Arivela limmenensis, Arivela linophylla, Arivela lophosperma, Arivela microaustralica, Arivela tetrandra, Arivela uncifera, Corynandra aspera, and Corynandra simplicifolia. Arivela microphylla is raised to species level and provided with a new combination.

Cleome, as traditionally defined, is not monophyletic and we here work towards taxonomic revisions for the Cleomaceae where genera reflect morphologically diagnosable monophyletic groups based on previous phylogenetic studies. We provide morphological characters to distinguish eight genera of predominantly African distribution, four of which are new to science: Coalisina, Dipterygium, Gilgella, Kersia, Puccionia, Sieruela, Stylidocleome, and Thulinella. We present new combinations in these genera for 52 species, four subspecies, and seven varieties. Two hundred and thirteen nomenclatural synonyms (homotypic and heterotypic) are treated, as well as nine generic synonyms. Fifty-one lectotypes are designated and two neotypes are created. A key is provided for all 13 genera (native and introduced) found in Africa.

Photosynthetic pathway innovations have had a large impact on patterns of diversification of angiosperm lineages and the biogeographic distribution of ecological assemblages. C4 photosynthesis has been one of the most studied processes in plants with respect to function, structure, occurrence, and response to climatic conditions. One of the most promising areas of research of C4 photosynthesis is in the Cleomaceae. Here we explore the phylogenetic origins of the C4 pathway in the Cleomaceae using maximum parsimony, maximum likelihood, and Bayesian inference analyses of nrDNA ITS sequences. As has been found previously, commonly recognized genera including Buhsia, Cleomella, Dactylaena, Gynandropsis, Isomeris, Oxystylis, Podandrogyne, Polanisia, and Wizlizenia are derived from within a paraphyletic Cleome. The phylogenetic results presented here indicate that there are likely at least five separate origins of carbon concentrating mechanisms in the Cleomaceae, including at least three separate orig...

Many genera previously placed in the traditionally circumscribed Capparaceae are either unrelated or, more commonly, isolated lineages in the order Brassicales. This study examines the relationships of three of these orphan genera, Emblingia, Forchhammeria, and Tirania, in the context of a focused analysis of the core Brassicales. In order to assess relationships of these genera, analyses were conducted across Brassicales using chloroplast rbcL, ndhF, and matK sequence information. Both maximum parsimony and maximum likelihood analyses place all three genera in the well-supported core Brassicales (Brassicaceae, Capparaceae, Cleomaceae, Gyrostemonaceae, Pentadiplandraceae, Resedaceae, and Tovariaceae). The Asiatic Tirania and New World tropical Forchhammeria are closely related to two small families, the pan-temperate Resedaceae and the Australian Gyrostemonaceae. These analyses also indicate a novel placement of Emblingia as sister to all remaining members of core Brassicales. Although there is strong support for the relationships among most of these taxa, relationships of Pentadiplandraceae and Tovariaceae are weakly resolved. Thus, the core Brassicales is a biogeographically dispersed lineage that is comprised of many small and morphologically distinct clades plus the large crown group Brassicaceae s. lat. Patterns of morphological evolution appear complex, especially in floral merosity and carpel and locule number. Likewise, the evolution of breeding systems within this lineage involves recurrent shifts towards monoecy or dioecy, and possible reversals to bisexuality. Further sampling of Capparaceae tribe Stixeae is critical for any taxonomic recommendation of familial status for these orphan genera.