Jumping through the hoops: the challenges of daffodil (Narcissus) classification

Abstract

AbstractHoop-petticoat daffodils are a morphologically congruent group comprised of two distinct lineages in molecular phylogenetic trees of Narcissus. It is possible that the morphological similarity is a product of both historic and current low-level gene flow between these lineages. For the first time, we report population sampling from across the entire range of distribution covering the Iberian Peninsula and Morocco. In total, 455 samples were collected from 59 populations. Plastid DNA sequences of matK and ndhF were generated alongside 11 microsatellite loci to permit comparison between plastid and nuclear lineage histories. The plastid DNA phylogenetic tree was highly congruent with previous molecular studies and supported the recognition of these two lineages of hoop-petticoat daffodils as separate sections. Assignment of samples to sections sometimes differed between plastid DNA and (nuclear) microsatellite data. In these cases, the taxa had previously been the focus of dissent in taxonomic placement based on morphology. These discrepancies could be explained by hybridization and introgression among the two lineages during the evolution of hoop-petticoat daffodils, and shows that placement of species in sections is dependent on the source of data used. This study underlines the complex evolutionary history of Narcissus and highlights the discrepancies between floral morphology and phylogeny, which provides a continuing challenge for the systematics of Narcissus.