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The Morelloid clade, also known as the black nightshades or "Maurella" (Morella), is one of the 10 major clades within the mega-diverse genus Solanum L. The clade is most diverse in the central to southern Andes, but species occur around the tropics and subtropics, some extending well into the temperate zone. Plants of the group vary from herbs to short-lived perennials to perennial shrubs that are distinctly woody at the base, they have small mostly white or purplish white flowers and small juicy berries. Due to the complex morphological variation and weedy nature of these plants, coupled with the large number of published synonyms (especially for European taxa), our understanding of species limits and diversity in the Morelloid clade has lagged behind that of other clades in Solanum . Here we provide the last in a three-part series of monographic treatments of the morelloid solanums (see PhytoKeys Vols. 106, 125), treating the 62 species occurring in South America. This region is by far the most diverse in the clade, both in terms of species number and morphological diversity. We provide complete synonymy, nomenclatural details, including lecto- and neotypifications where needed, common names and uses, morphological descriptions, illustrations to aid identification both in herbaria and in the field, and distribution maps for all native, non-cultivated species. We include a key to all species, a synoptic character list for the species treated here and links to synoptic online keys for all species of the Morelloid clade. Preliminary conservation assessments following IUCN guidelines are also provided for all native species., Competing Interests: The authors have declared that no competing interests exist., (Sandra Knapp, Tiina Särkinen, Gloria E. Barboza.)

Poor morphological and molecular differentiation in recently diversified lineages is a widespread phenomenon in plants. Phylogenetic relationships within such species complexes are often difficult to resolve because of the low variability in traditional molecular loci. Furthermore, biological phenomena responsible for topological incongruence such as Incomplete Lineage Sorting (ILS) and hybridisation complicate the resolution of phylogenetic relationships among closely related taxa. In this study, we employ a Genotyping-by-sequencing (GBS) approach to disentangle evolutionary relationships within a species complex belonging to the Neotropical orchid genus Cycnoches. This complex includes seven taxa distributed through Central America and the Colombian Chocó, and is nested within a clade estimated to have first diversified in the early Quaternary. Previous phylogenies inferred from few loci failed to provide support for internal relationships within the complex. Our Neighbour-net and coalescent-based analyses inferred from ca. 13,000 GBS loci obtained from 31 individuals belonging to six of the seven traditionally accepted Cycnoches taxa provided a robust phylogeny for this group. The genus Cycnoches includes three main clades that are further supported by morphological traits and geographic distributions. Similarly, a topology reconstructed through maximum likelihood (ML) inference of concatenated GBS loci produced results that are comparable with those reconstructed through coalescence and network-based methods. Our comparative phylogenetic informativeness analyses suggest that the low support evident in the ML phylogeny might be attributed to the abundance of uninformative GBS loci, which can account for up to 50% of the total number of loci recovered. The phylogenomic framework provided here, as well as morphological evidence and geographical patterns, suggest that the six entities previously thought to be different species or subspecies might actually represent only three distinct segregates. We further discuss the limited phylogenetic informativeness found in our GBS approach and its utility to disentangle relationships within recent and rapidly evolving species complexes. Our study is the first to demonstrate the utility of GBS data to reconstruct relationships within young (~2 Ma) Neotropical plant clades, opening new avenues for studies of species complexes that populate the species-rich orchid family., (Copyright © 2019. Published by Elsevier Inc.)

After an absence of ≈200 years, chikungunya returned to the American tropics in 2013. The virus is maintained in a complex African zoonotic cycle but escapes into an urban cycle at 40- to 50-year intervals, causing global pandemics. In 1823, classical chikungunya, a viral exanthem in humans, occurred on Zanzibar, and in 1827, it arrived in the Caribbean and spread to North and South America. In Zanzibar, the disease was known as kidenga pepo, Swahili for a sudden cramp-like seizure caused by an evil spirit; in Cuba, it was known as dengue, a Spanish homonym of denga. During the eighteenth century, dengue (present-day chikungunya) was distinguished from breakbone fever (present-day dengue), another febrile exanthem. In the twentieth century, experiments resulted in the recovery and naming of present-day dengue viruses. In 1952, chikungunya virus was recovered during an outbreak in Tanzania, but by then, the virus had lost its original name to present-day dengue viruses.