All pieces together now? A phylogenomic analysis and tribe‐level classification of the heterogeneous family Plantaginaceae

Abstract

The plant family Plantaginaceae comprises approximately 2100 species in 106 genera, representing around 1% of all eudicots. The current circumscription of the family has been established in recent decades based on insights from DNA‐based phylogenetic analyses, which have united genera previously considered unrelated. Consequently, the family exhibits a worldwide distribution and immense diversity in habitats and morphological traits, ranging from aquatic herbs in tropical regions, through alpine genera in the Himalayas, to carnivorous plants on low‐nutrient sandy soils. Here, we present the first phylogenomic analysis and the most comprehensive study on Plantaginaceae systematics to date in terms of taxon coverage, addressing several uncertainties and providing new insights into relationships within and among tribes. This is achieved through high‐throughput sequencing in combination with the Angiosperms353 probe kit. A concatenated and a coalescent tree were built, based on an alignment of 132 individuals, representing 92–99 genera. All 12 tribes were recovered as monophyletic. Notably, we found that genera Ildefonsia and Uroskinnera are not members of the family, and we evaluated the relationships of Cheilophyllum and Kashmiria for the first time. The results are discussed in the form of a tribe‐based review, offering an overview of the classification history of the tribe, past and current placements of genera and outstanding questions that remain to be solved.