Phylogenetic and biogeographical inferences for Pancratium (Amaryllidaceae), with an emphasis on the Mediterranean species based on plastid sequence data

Abstract

The phylogenetics and biogeography of Pancratium (Amaryllidaceae) were investigated, with a focus on the Mediterranean and adjacent areas, with the aim of contributing new information towards a better understanding of the evolutionary history of the genus and the taxonomic placement of P.linosae and P.hirtum. To address these questions, we sequenced four plastid DNA markers: the ndhF and rbcL genes, the trnL (UAA)-trnF (GAA) intergenic spacer and the trnL (UAA) intron, analysing them using parsimony, likelihood and Bayesian approaches. The results show that the relationships among the majority of the species are resolved; however, the relationships of one of the major clades of the genus are unresolved compared with the others. The phylogenetic and the dispersal-vicariance analyses show that Pancratium appears as a well-structured group with interesting patterns of speciation. Notably, P.arabicum and P.linosae fall within the P.maritimum complex. In addition, P.hirtum is identical, in terms of plastid DNA sequences, to the P.trianthum accessions. The results provide new insights and help to formulate new working hypotheses for evolutionary biology of the genus. © 2012 The Linnean Society of London.