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Interspecific hybridization events have played a major role in plant speciation, yet the evolutionary origin of hybrid species often remains enigmatic. Here, we inferred the evolutionary origin of the allotetraploid species Coffea arabica, which is widely cultivated for Arabica coffee production. We estimated genetic distances between C. arabica and all species that are known to be closely related to C. arabica using genotyping‐by‐sequencing (GBS) data. In addition, we reconstructed a time‐calibrated multilabeled phylogenetic tree of 24 species to estimate the age of the C. arabica hybridization event. Ancestral states of self‐compatibility were also inferred to shed new light on the evolution of self‐compatibility in Coffea. Coffea canephora and C. eugenioides were confirmed as the putative progenitor species of C. arabica. These species most likely hybridized between 1.08 million and 543 000 years ago, coinciding with periods of environmental upheaval, which may have induced range shifts of the progenitor species that facilitated the emergence of C. arabica. [ABSTRACT FROM AUTHOR]

To effectively monitor, manage and protect aquatic species and understand their interactions, knowledge of their spatiotemporal distribution is needed. In this study, we used a fine‐scale spatiotemporal water sampling design, followed by environmental DNA (eDNA) 12S metabarcoding, to investigate occupancy patterns of a natural community of fish and amphibian species in a lentic system. In the same system, we experimentally estimated the spatial and temporal dispersion of eDNA by placing a community of different fish and amphibian species in cages at one side of the pond, creating a controlled point of eDNA emission. Analyses of this cage community revealed a sharp spatial decline in detection rates and relative eDNA quantities at a distance of 5–10 m from the source, depending on the species and its abundance. In addition, none of the caged species could be detected 1 week after removal from the system. This indicates high eDNA decay rates and limited spatial eDNA dispersal, facilitating high local resolution for monitoring spatial occupancy patterns of aquatic species. Remarkably, for seven of the nine cage species, the presence of a single individual could be detected by pooling water of subsamples taken across the whole water body, illustrating the high sensitivity of the eDNA sampling and detection method applied. Finally, our work demonstrated that a fine‐scale sampling design in combination with eDNA metabarcoding can cover total biodiversity very precisely and allows the construction of consistent spatiotemporal patterns of relative abundance and local distribution of free‐living fish and amphibian species in a lentic ecosystem. [ABSTRACT FROM AUTHOR]