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Abstract Background A robust molecular phylogeny is fundamental for developing a stable classification and providing a solid framework to understand patterns of diversification, historical biogeography, and character evolution. As the sixth largest angiosperm family, Lamiaceae, or the mint family, consitutes a major source of aromatic oil, wood, ornamentals, and culinary and medicinal herbs, making it an exceptionally important group ecologically, ethnobotanically, and floristically. The lack of a reliable phylogenetic framework for this family has thus far hindered broad-scale biogeographic studies and our comprehension of diversification. Although significant progress has been made towards clarifying Lamiaceae relationships during the past three decades, the resolution of a phylogenetic backbone at the tribal level has remained one of the greatest challenges due to limited availability of genetic data. Results We performed phylogenetic analyses of Lamiaceae to infer relationships at the tribal level using 79 protein-coding plastid genes from 175 accessions representing 170 taxa, 79 genera, and all 12 subfamilies. Both maximum likelihood and Bayesian analyses yielded a more robust phylogenetic hypothesis relative to previous studies and supported the monophyly of all 12 subfamilies, and a classification for 22 tribes, three of which are newly recognized in this study. As a consequence, we propose an updated phylogenetically informed tribal classification for Lamiaceae that is supplemented with a detailed summary of taxonomic history, generic and species diversity, morphology, synapomorphies, and distribution for each subfamily and tribe. Conclusions Increased taxon sampling conjoined with phylogenetic analyses based on plastome sequences has provided robust support at both deep and shallow nodes and offers new insights into the phylogenetic relationships among tribes and subfamilies of Lamiaceae. This robust phylogenetic backbone of Lamiaceae will serve as a framework for future studies on mint classification, biogeography, character evolution, and diversification. Graphical abstract 

Paralamium (Lamiaceae) is a monotypic genus within the subfamily Lamioideae and has a sporadic distribution in subtropical mountains of southeast Asia. Although recent studies have greatly improved our understanding of generic relationships within Lamioideae, the second most species-rich subfamily of Lamiaceae, the systematic position of Paralamium within the subfamily remains unclear. In this study, we investigate the phylogenetic placement of the genus using three datasets: (1) a 69,276 bp plastome alignment of Lamiaceae; (2) a five chloroplast DNA region dataset of tribe Pogostemoneae, and (3) a nuclear ribosomal internal transcribed spacer region dataset of Pogostemoneae. These analyses demonstrate that Paralamium is a member of Pogostemoneae and sister to the monotypic genus Craniotome . In addition, generic-level phylogenetic relationships within Pogostemoneae are also discussed, and a dichotomous key for genera within Pogostemoneae is provided. 

The northern temperate genusDracocephalumconsists of approximately 70 species mainly distributed in the steppe‐desert biomes of Central and West Asia and the alpine region of the Qinghai‐Tibetan Plateau (QTP). Previous work has shown thatDracocephalumis not monophyletic and might includeHyssopusandLallemantia. This study attempts to clarify the phylogenetic relationships, diversification patterns, and the biogeographical history of the three genera (defined asDracocephalums.l.). Based on a sampling of 66 taxa comprising more than 80% from extant species ofDracocephalums.l., morphological, phylogenetic (maximum parsimony, likelihood, and Bayesian inference based on nuclear ITS and ETS, plastidrpl32‐trnL,trnL‐trnF,ycf1, andycf1‐rps15, and two low‐copy nuclear markersAT3G09060andAT1G09680), molecular dating, diversification, and ancestral range estimation analyses were carried out. Our results demonstrate that bothHyssopusandLallemantiaare embedded withinDracocephalumand nine well‐supported clades can be recognized withinDracocephalums.l. Analyses of divergence times suggest that the genus experienced an early rapid radiation during the middle to late Miocene with major lineages diversifying within a relatively narrow timescale. Ancestral area reconstruction analyses indicate thatDracocephalums.l. originated in Central and West Asia and southern Siberia, and dispersed from Central and West Asia into the QTP and adjacent areas twice independently during the Pliocene. The aridification of the Asian interior possibly promoted the rapid radiation ofDracocephalumwithin this region, and the uplift of the QTP appears to have triggered the dispersal and recent rapid diversification of the genus in the QTP and adjacent regions. Combining molecular phylogenetic and morphological evidence, a revised infrageneric classification ofDracocephalums.l. is proposed, which recognizes nine sections within the genus.