Examining the needle in the haystack: Evolutionary relationships in the mistletoe genus Loranthus Jacq. (Loranthaceae)

The genus Loranthus Jacq. (Loranthaceae) consists of ca. nine Old World species distributed from eastern Asia to Europe. Loranthus, the type of the family, has had a complex taxonomic history that continues today, partly because most mistletoes in the family have resided in this genus. For this reason, there are over 1800 Loranthus species names, the vast majority of which are synonyms for mistletoes in other genera. The present work sampled representatives of nine species considered bona fide members of the genus. Using complete plastome sequences, nuclear ribosomal DNA, and mitochondrial 26S rDNA, phylogenetic gene trees were generated to assess interspecific relationships. The Loranthus plastomes ranged in size from 121 to 125 kb and exhibited the quadripartite structure seen in most Santalales. These plastomes have lost or pseudogenized 24 genes, including all of the NADH dehydrogenase complex, thus reducing the genomes to ca. 90 functional genes. Cladistic analyses of morphological...