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The Atacama Desert harbors a unique arid-adapted flora with a high degree of endemism, the origin of which is poorly understood. In the Atacama Desert, Zygophyllaceae is represented by five endemic species: one member of Zygophylloideae: Fagonia chilensis; and four members of Larreoideae: Bulnesia chilensis and Porlieria chilensis, the only representatives in the Atacama Desert of genera with disjunct distributions between Argentina, Peru and Chile; and monotypic endemic genera Metharme lanata and Pintoa chilensis. Zygophyllaceae are thus a particularly suitable group for studying the historical assembly of the Atacama Desert flora as each of these species may represent independent biogeographical events. We made use of published as well as original plastid DNA sequences (rbcL, trnL-trnF & trnS-trnG) to reevaluate the phylogenetic relationships of the Atacama Zygophyllaceae. Bayesian divergence time estimates as implemented in BEAST2 and ancestral area reconstruction with the Dispersal Extinction Cladogenesis approach using BioGeoBEARS were applied to infer ancestral ranges. We compiled the most complete data set of Larreoideae to date with 25 of 28 species. Bulnesia rivas-martinezii from Bolivia forms a clade with Pintoa chilensis from the Atacama Desert, rendering the genus Bulnesia paraphyletic. Most representatives of Zygophyllaceae colonized the Atacama Desert during the Miocene, and only Fagonia dispersed more recently. The colonization history of the Atacama Desert in South America is reflected by three individual distribution patterns or floristic elements. The presence of Bulnesia, Pintoa, and Metharme is best explained by Andean vicariance, while the southern Atacama Desert representative, Porlieria chilensis, has a continuous distribution into central Chile from where it probably dispersed further north. The only South American Fagonia species (F. chilensis) likely colonized the Chilean-Peruvian Coastal Desert via long distance dispersal from North America.

Premise: Plants generate a wide array of signals such as olfactory cues to attract and manipulate the response of pollinators. The present study addresses the temporal patterns of scent emission as an additional dimension to the scent composition. The expectation is that divergent floral function is reflected in divergent qualitative and temporal emission patterns. Methods: We used GC‐ion mobility spectrometry with an integrated pre‐concentration for automated acquisition of the temporal trends in floral volatile emissions for N. viridiflorus, N. papyraceus, and N. cantabricus subsp. foliosus. Results: We found a considerable increase in scent emissions and changes in scent composition for N. viridiflorus at night. This increase was particularly pronounced for aromatic substances such as benzyl acetate and p‐cresol. We found no diurnal patterns in N. papyraceus, despite a similar qualitative composition of floral volatiles. Narcissus cantabricus subsp. foliosus showed no diurnal patterns either and differed considerably in floral scent composition. Conclusions: Scent composition, circadian emission patterns, and floral morphology indicate divergent, but partially overlapping pollinator communities. However, the limited pollinator data from the field only permits a tentative correlation between emission patterns and flower visitors. Narcissus papyraceus and N. cantabricus show no clear diurnal patterns and thus no adjustment to the activity patterns of their diurnal pollinators. In N. viridiflorus, timing of scent emission indicates an adaptation to nocturnal flower visitors, contradicting Macroglossum as the only reported pollinator. We propose that the legitimate pollinators of N. viridiflorus are nocturnal and are still unidentified. [ABSTRACT FROM AUTHOR]

The genus Ribes (Grossulariaceae) is widespread across the northern hemisphere, but also species-rich in the tropical Andes. In the Peruvian Andes the genus is mostly found in at least seasonally moist cloud and scrub forests, subparamo habitats and hedges. However, some taxa are from more extreme habitats in semi-arid habitats of the western slope of the Andes (Andean scrub, Ribes ovalifolium) respectively high Andean puna and paramo habitats at elevations of up to 5100 m asl (Ribes cuneifolium and some doubtful segregates). These species share small, weakly divided leaves, making them quite atypical for the genus, usually with large, deeply three- to five-lobed leaves. Both the geographical ranges and the species delimitation for both taxa are poorly understood. We here propose the recognition of only two, well-differentiated species. Ribes ovalifolium can be shown to be wide-ranging from northern Ancash to Tacna, covering nearly the entire western flank of the Peruvian Andes. Similarly, Ribes cuneifolium can be shown to represent a single, wide-ranging species from high elevations of San Martín/La Libertad to Cuzco. There is considerable diversity on details of indument, flower color and leaf shape, but no clear dividing lines permitting the recognition of segregates such as Ribes incertum J.F.Macbr. The only exception are cloud-forest populations of Ribes cuneifolium in Pasco, which we propose to segregate as a new subspecies Ribes cuneifolium subsp. pascoense based on their considerably larger leaves and inflorescences.