Phylogeny and staminal evolution of Salvia (Lamiaceae, Nepetoideae) in East Asia

Evolution and chemical diversity of the volatile compounds in Salvia species

INTRODUCTION

The plant essential oils are composed of volatile compounds and have significant value in preventing and treating neurological diseases, anxiety, depression, among others. The genus Salvia has been shown to be an important medicinal resource, especially the aerial parts of genus Salvia, which are rich in volatile compounds; however, the chemical diversity and distribution patterns of volatile compounds in Salvia species are still unknown.

OBJECTIVE

The work is performed to analyse the chemical diversity and distribution patterns of volatile compounds in genus Salvia.

METHODS

The genomic single nucleotide polymorphisms (SNPs) combined with gas chromatography-mass spectrometry (GC-MS) were used to explore the evolution and chemical diversity of Salvia volatile compounds. Initially, the genetic relationship of genus Salvia was revealed by phylogenetic tree that was constructed based on SNPs. And then, GC-MS was applied to explore the chemical diversity of volatile compounds.

RESULTS

The results indicated that the volatile compounds were mainly monoterpenoids, sesquiterpenoids, and aliphatic compounds. The genomic SNPs divided species involved in this work into four branches. The volatile compounds in the first and second branches were mainly sesquiterpenoids and monoterpenoids, respectively. Species in the third branch contained more aliphatic compounds and sesquiterpenoids. And those in the fourth branch were also rich in monoterpenoids but had relatively simple chemical compositions.

CONCLUSION

This study offered new insights into the phylogenetic relationships besides chemistry diversity and distribution pattern of volatile compounds of genus Salvia, providing theoretical guidance for the investigations and development of secondary metabolites.

Salvia guidongensis sp. nov.: unraveling a critical evolutionary link in East Asian Salvia from Central China integrating morphology, phylogeny, and plastid genomics

Introduction

Salvia L., representing the largest genus within the mint family, is noted for its global distribution of approximately 1000 species, with East Asia, and particularly China, recognized as a critical center of diversity for the genus.

Methods

Our research was conducted through extensive fieldwork in Guidong County, Hunan Province, China, where we identified a previously undescribed species of Salvia. The identification process involved detailed morphological observations, phylogenetic analyses, and plastid genomics.

Results

The newly discovered species, Salvia guidongensis, exhibits unique characteristics not commonly observed in the East Asian lineage of Salvia, including dual floral colors within natural populations-either pale purple or pale yellow. Morphologically, while it shares similarities with members of sect. Glutinaria, S. guidongensis is distinct in its floral morphology, stature, and specific foliar traits. Phylogenetic analysis places S. guidongensis in a unique clade within the East Asian lineage of Salvia, suggesting it may serve as an important evolutionary link. Additionally, we explored the plastome features of S. guidongensis, comparing them with those of closely related species.

Discussion

The discovery of S. guidongensis not only entriches the taxonomic tapestry of Salvia but also provides critical insights into the biogeography and evolutionary pathways of the genus in East Asia. By integrating morphological and molecular data, we validate the novel status of S. guidongensis and highlight its significance in bridging taxonomic and evolutionary gaps within Sect. Glutinaria of Salvia.

Genome-Wide Identification and Expression Analysis of the MYB Transcription Factor Family in Salvia nemorosa

The MYB transcription factor gene family is among the most extensive superfamilies of transcription factors in plants and is involved in various essential functions, such as plant growth, defense, and pigment formation. Salvia nemorosa is a perennial herb belonging to the Lamiaceae family, and S. nemorosa has various colors and high ornamental value. However, there is little known about its genome-wide MYB gene family and response to flower color formation. In this study, 142 SnMYB genes (MYB genes of S. nemorosa) were totally identified, and phylogenetic relationships, conserved motifs, gene structures, and expression profiles during flower development stages were analyzed. A phylogenetic analysis indicated that MYB proteins in S. nemorosa could be categorized into 24 subgroups, as supported by the conserved motif compositions and gene structures. Furthermore, according to their similarity with AtMYB genes associated with the control of anthocyanin production, ten SnMYB genes related to anthocyanin biosynthesis were speculated and chosen for further qRT-PCR analyses. The results indicated that five SnMYB genes (SnMYB75, SnMYB90, SnMYB6, SnMYB82, and SnMYB12) were expressed significantly differently in flower development stages. In conclusion, our study establishes the groundwork for understanding the anthocyanin biosynthesis of the SnMYB gene family and has the potential to enhance the breeding of S. nemorosa.

Cytotoxic diterpenoids from Salvia glutinosa and comparison with the tanshinone profile of danshen (Salvia miltiorrhiza)

The roots of Salvia miltiorrhiza are the source of the traditional Chinese medicine danshen and the class of tanshinones, particular quinoid nor-diterpenoids of the abietane type. Of these compounds, cryptotanshinone, dihydrotanshinone I, tanshinone I, and tanshinone IIA, have been extensively studied for their anticancer potential, not only but as well because of their high abundance in S. miltiorrhiza and their thus easy availability. However, also additional Salvia species are known to contain tanshinones, mainly such of the subgenus Glutinaria, of which S. glutinosa is the only species widely occurring in Europe. Using UHPLC-DAD-MS, the tanshinone profile of S. glutinosa roots collected from two different locations was compared to the profile in S. miltiorrhiza roots. In addition, tanshinone IIA and another six diterpenoids from S. glutinosa were investigated for their antiproliferative and cytotoxic potential against MDA-MB-231 and HL-60 cells. Apart from dihydrotanshinone I, which has been previously characterized due to its anticancer properties, we determined danshenol A as a highly antiproliferative and cytotoxic agent, significantly surpassing the effects of dihydrotanshinone I. With regard to the diterpenoid profile, S. miltiorrhiza showed a higher concentration for most of the tanshinones, except for (+)-danshexinkun A, which was present in comparable amounts in both species. Danshenol A, in contrast, was only present in S. glutinosa as were dehydroabietic acid and (+)-pisiferic acid. The results of our study underlines the long traditional use of danshen due to its high amount on tanshinones, but also demonstrates the potential value of investigating closely related species for the discovery of new biologically active lead compounds.

Comparative and phylogenetic analysis of complete chloroplast genome sequences of Salvia regarding its worldwide distribution

Salvia is widely used as medicine, food, and ornamental plants all over the world, with three main distribution centers, the Central and western Asia/Mediterranean (CAM), the East Aisa (EA), and the Central and South America (CASA). Along with its large number of species and world-wide distribution, Salvia is paraphyletic with multiple diversity. Chloroplast genomes (CPs) are useful tools for analyzing the phylogeny of plants at lower taxonomic levels. In this study, we reported chloroplast genomes of five species of Salvia and performed phylogenetic analysis with current available CPs of Salvia. Repeated sequence analysis and comparative analysis of Salvia CPs were also performed with representative species from different distribution centers. The results showed that the genetic characters of the CPs are related to the geographic distribution of plants. Species from CAM diverged first to form a separate group, followed by species from EA, and finally species from CASA. Larger variations of CPs were observed in species from CAM, whereas more deficient sequences and less repeated sequences in the CPs were observed in species from CASA. These results provide valuable information on the development and utilization of the worldwide genetic resources of Salvia.

Functional divergence of CYP76AKs shapes the chemodiversity of abietane-type diterpenoids in genus Salvia

The genus Salvia L. (Lamiaceae) comprises myriad distinct medicinal herbs, with terpenoids as one of their major active chemical groups. Abietane-type diterpenoids (ATDs), such as tanshinones and carnosic acids, are specific to Salvia and exhibit taxonomic chemical diversity among lineages. To elucidate how ATD chemical diversity evolved, we carried out large-scale metabolic and phylogenetic analyses of 71 Salvia species, combined with enzyme function, ancestral sequence and chemical trait reconstruction, and comparative genomics experiments. This integrated approach showed that the lineage-wide ATD diversities in Salvia were induced by differences in the oxidation of the terpenoid skeleton at C-20, which was caused by the functional divergence of the cytochrome P450 subfamily CYP76AK. These findings present a unique pattern of chemical diversity in plants that was shaped by the loss of enzyme activity and associated catalytic pathways.

Unveiling the spatial distribution and molecular mechanisms of terpenoid biosynthesis in Salvia miltiorrhiza and S. grandifolia using multi-omics and DESI-MSI

Salvia miltiorrhiza and S. grandifolia are rich in diterpenoids and have therapeutic effects on cardiovascular diseases. In this study, the spatial distribution of diterpenoids in both species was analyzed by a combination of metabolomics and mass spectrometry imaging techniques. The results indicated that diterpenoids in S. miltiorrhiza were mainly abietane-type norditerpenoid quinones with a furan or dihydrofuran D-ring and were mainly distributed in the periderm of the roots, e.g. cryptotanshinone and tanshinone IIA. The compounds in S. grandifolia were mainly phenolic abietane-type tricyclic diterpenoids with six- or seven-membered C-rings, and were widely distributed in the periderm, phloem, and xylem of the roots, e.g. 11-hydroxy-sugiol, 11,20-dihydroxy-sugiol, and 11,20-dihydroxy-ferruginol. In addition, the leaves of S. grandifolia were rich in tanshinone biosynthesis precursors, such as 11-hydroxy-sugiol, while those of S. miltiorrhiza were rich in phenolic acids. Genes in the upstream pathway of tanshinone biosynthesis were highly expressed in the root of S. grandifolia, and genes in the downstream pathway were highly expressed in the root of S. miltiorrhiza. Here, we describe the specific tissue distributions and mechanisms of diterpenoids in two Salvia species, which will facilitate further investigations of the biosynthesis of diterpenoids in plant synthetic biology.

Towards a global perspective for Salvia L.: Phylogeny, diversification and floral evolution

Salvia is the most species-rich genus in Lamiaceae, encompassing approximately 1000 species distributed all over the world. We sought a new evolutionary perspective for Salvia by employing macroevolutionary analyses to address the tempo and mode of diversification. To study the association of floral traits with speciation and extinction, we modelled and explored the evolution of corolla length and the lever-mechanism pollination system across our Salvia phylogeny. We reconstructed a multigene phylogeny for 366 species of Salvia in the broad sense including all major recognized lineages and 50 species from Iran, a region previously overlooked in studies of the genus. Our comprehensive sampling of Iranian species of Salvia provides higher phylogenetic resolution for southwestern Asian species than obtained in previous studies. Our phylogenetic data in combination with divergence time estimates were used to examine the evolution of corolla length, woody versus herbaceous habit, and presence versus absence of a lever mechanism. We investigated the timing and dependence of Salvia diversification related to corolla length evolution through a disparity test and BAMM analysis. A HiSSE model was used to evaluate the dependency of diversification on the lever-mechanism pollination system in Salvia. A medium corolla length (15-18 mm) was reconstructed as the ancestral state for Salvia with multiple shifts to shorter and longer corollas. Macroevolutionary model analyses indicate that corolla length disparity is high throughout Salvia evolution, significantly different from expectations under a Brownian motion model during the last 28 million years of evolution. Our analyses show evidence of a higher diversification rate of corolla length for some Andean species of Salvia compared to other members of the genus. Based on our tests of diversification models, we reject the hypothesis of a direct effect of the lever mechanism on Salvia diversification. Therefore, we suggest caution in considering the lever-mechanism pollination system as one of the main drivers of speciation in Salvia.

The complete chloroplast genome sequence of Salvia chienii E.Peter, 1936 (Lamiaceae)

Salvia chienii E.Peter is a medicinal herb mainly distributed in Huangshan Mountain of Anhui province, China. In this study, the first complete chloroplast genome of S. chienii was sequenced and assembled. The genome length was 151,530 bp and encoded 143 genes (91 protein-coding genes, eight rRNA genes, and 37 tRNA genes). The phylogenomic analysis showed that S. chienii was closely related to S. miltiorrhiza. Further evolutionary studies of the genus Salvia could benefit from the complete chloroplast genome of S. chienii present in this study.

Unusual patterns of hybridization involving two alpine Salvia species: Absence of both F1 and backcrossed hybrids

Natural hybridization plays an important role in speciation; however, we still know little about the mechanisms underlying the early stages of hybrid speciation. Hybrid zones are commonly dominated by F₁s, or backcrosses, which impedes further speciation. In the present study, morphological traits and double digest restriction-site associated DNA sequencing (ddRAD-seq) data have been used to confirm natural hybridization between Salvia flava and S. castanea, the first case of identification of natural hybridization using combined phenotypic and molecular evidence in the East Asian clade of Salvia. We further examined several reproductive barriers in both pre-zygotic and post-zygotic reproductive stages to clarify the causes and consequences of the hybridization pattern. Our results revealed that reproductive isolation between the two species was strong despite the occurrence of hybridization. Interestingly, we found that most of the hybrids were likely to be F₂s. This is a very unusual pattern of hybridization, and has rarely been reported before. The prevalence of geitonogamy within these self-compatible hybrids due to short distance foraging by pollinators might explain the origin of this unusual pattern. F₂s can self-breed and develop further, therefore, we might be witnessing the early stages of hybrid speciation. Our study provides a new case for understanding the diversification of plants on the Qinghai-Tibet Plateau.

Investigation of the Composition, Antimicrobial, Antioxidant, and Cytotoxicity Properties of Salvia abrotanoides Essential Oil

Medicinal plants present promising attributes in traditional medicine based on earlier published documents. Most of the essential oils derived from vascular plants display a significant role in dealing with microbial and inflammation infections. This research aimed to provide informative knowledge about the composition, antimicrobial, and anticytotoxicity of Salvia abrotanoides essential oil. In this study, the chemical composition of S. abrotanoides was determined using FTIR and GC-MS analysis which demonstrated the significant number of monoterpenes in the constitutes. The antimicrobial activity of EO demonstrated a dose-related effect on several pathogenic bacteria and fungi; among bacteria, Gram-positive bacteria exhibited more sensitivity to the essential oil antimicrobial compounds. On the other hand, S. abrotanoides essential oil did not present antifungal activity as high as Fluconazole on Aspergillus niger and Candida albicans. The total phenolic and flavonoid content of essential oil were determined as 14.70 ± 1.4 mg·GA/g essential oil and 2.93 ± 0.41 mg Q/g essential oil, respectively. The antioxidant activity of essential oils was investigated, and it was not as high as positive controls. Moreover, the microscopic changes of S. aureus and E. coli were investigated using SEM images. The cytotoxicity potential of essential oil was evaluated on L929 and A459 cell lines and also it was estimated to be stronger on A459 cell line than that of L929.

Comparative Genomics and Phylogenetic Analysis of the Chloroplast Genomes in Three Medicinal Salvia Species for Bioexploration

To systematically determine their phylogenetic relationships and develop molecular markers for species discrimination of Salvia bowleyana, S. splendens, and S. officinalis, we sequenced their chloroplast genomes using the Illumina Hiseq 2500 platform. The chloroplast genomes length of S. bowleyana, S. splendens, and S. officinalis were 151,387 bp, 150,604 bp, and 151,163 bp, respectively. The six genes ndhB, rpl2, rpl23, rps7, rps12, and ycf2 were present in the IR regions. The chloroplast genomes of S. bowleyana, S. splendens, and S. officinalis contain 29 tandem repeats; 35, 29, 24 simple-sequence repeats, and 47, 49, 40 interspersed repeats, respectively. The three specific intergenic sequences (IGS) of rps16-trnQ-UUG, trnL-UAA-trnF-GAA, and trnM-CAU-atpE were found to discriminate the 23 Salvia species. A total of 91 intergenic spacer sequences were identified through genetic distance analysis. The two specific IGS regions (trnG-GCC-trnM-CAU and ycf3-trnS-GGA) have the highest K2p value identified in the three studied Salvia species. Furthermore, the phylogenetic tree showed that the 23 Salvia species formed a monophyletic group. Two pairs of genus-specific DNA barcode primers were found. The results will provide a solid foundation to understand the phylogenetic classification of the three Salvia species. Moreover, the specific intergenic regions can provide the probability to discriminate the Salvia species between the phenotype and the distinction of gene fragments.

The Flavone Cirsiliol from Salvia x jamensis Binds the F1 Moiety of ATP Synthase, Modulating Free Radical Production

Several studies have shown that mammalian retinal rod outer segments (OS) are peculiar structures devoid of mitochondria, characterized by ectopic expression of the molecular machinery for oxidative phosphorylation. Such ectopic aerobic metabolism would provide the chemical energy for the phototransduction taking place in the OS. Natural polyphenols include a large variety of molecules having pleiotropic effects, ranging from anti-inflammatory to antioxidant and others. Our goal in the present study was to investigate the potential of the flavonoid cirsiliol, a trihydroxy-6,7-dimethoxyflavone extracted from Salvia x jamensis, in modulating reactive oxygen species production by the ectopic oxidative phosphorylation taking place in the OS. Our molecular docking analysis identified cirsiliol binding sites inside the F1 moiety of the nanomotor F₁F_o-ATP synthase. The experimental approach was based on luminometry, spectrophotometry and cytofluorimetry to evaluate ATP synthesis, respiratory chain complex activity and H₂O₂ production, respectively. The results showed significant dose-dependent inhibition of ATP production by cirsiliol. Moreover, cirsiliol was effective in reducing the free radical production by the OS exposed to ambient light. We report a considerable protective effect of cirsiliol on the structural stability of rod OS, suggesting it may be considered a promising compound against oxidative stress.

Microhabitat and Pollinator Differentiation Drive Reproductive Isolation between Two Sympatric Salvia Species (Lamiaceae)

Evaluation of multiple barriers contributing to reproductive isolation between sympatric plant species is key to understanding the mechanism of their coexistence; however, such investigations in biodiversity hotspots are still rare. In this study, we investigated and compared geography, microhabitat, phenology, flora, and pollinators, in addition to pollen–pistil interactions, seed production, and seed germination of the closely related sympatric Salvia digitaloides and S. flava on Yulong Snow Mountain, Southwestern Yunnan, China. The geographic distribution of these species overlapped, but their adaptation to physical and chemical properties of soil microhabitats differed. They shared the same flowering time but differed in flower size, style length, nectar volume, sugar concentration, and flower longevity. Both species shared bumblebees as effective pollinators, but flower constancy for the two species was relatively strong. Pollen tube growth, seed production, and seed germination were lower in interspecific than in intraspecific crosses. Our study suggested that microhabitat and pollinator isolation acted as the most important isolating barriers in maintaining the coexistence of the two Salvia species. Our study also highlighted that post-pollination barriers play an important role in preventing the gene flow between these two Salvia species.

Integration of Repeatomic and Cytogenetic Data on Satellite DNA for the Genome Analysis in the Genus Salvia (Lamiaceae)

Within the complicated and controversial taxonomy of cosmopolitan genus Salvia L. (Lamiaceae) are valuable species Salvia officinalis L. and Salvia sclarea L., which are important for the pharmaceutical, ornamental horticulture, food, and perfume industries. Genome organization and chromosome structure of these essential oil species remain insufficiently studied. For the first time, the comparative repeatome analysis of S. officinalis and S. sclarea was performed using the obtained NGS data, RepeatExplorer/TAREAN pipelines and FISH-based chromosome mapping of the revealed satellite DNA families (satDNAs). In repeatomes of these species, LTR retrotransposons made up the majority of their repetitive DNA. Interspecific variations in genome abundance of Class I and Class II transposable elements, ribosomal DNA, and satellite DNA were revealed. Four (S. sclarea) and twelve (S. officinalis) putative satDNAs were identified. Based on patterns of chromosomal distribution of 45S rDNA; 5S rDNA and the revealed satDNAs, karyograms of S. officinalis and S. sclarea were constructed. Promising satDNAs which can be further used as chromosome markers to assess inter- and intraspecific chromosome variability in Salvia karyotypes were determined. The specific localization of homologous satDNA and 45S rDNA on chromosomes of the studied Salvia species confirmed their common origin, which is consistent with previously reported molecular phylogenetic data.

The sage genome provides insight into the evolutionary dynamics of diterpene biosynthesis gene cluster in plants

The widely cultivated medicinal and ornamental plant sage (Salvia officinalis L.) is an evergreen shrub of the Lamiaceae family, native to the Mediterranean. We assembled a high-quality sage genome of 480 Mb on seven chromosomes, and identified a biosynthetic gene cluster (BGC) encoding two pairs of diterpene synthases (diTPSs) that, together with the cytochromes P450 (CYPs) genes located inside and outside the cluster, form two expression cascades responsible for the shoot and root diterpenoids, respectively, thus extending BGC functionality from co-regulation to orchestrating metabolite production in different organs. Phylogenomic analysis indicates that the Salvia clades diverged in the early Miocene. In East Asia, most Salvia species are herbaceous and accumulate diterpenoids in storage roots. Notably, in Chinese sage S. miltiorrhiza, the diterpene BGC has contracted and the shoot cascade has been lost. Our data provide genomic insights of micro-evolution of growth type-associated patterning of specialized metabolite production in plants.

Species conservation profile and revision of Salviakorolkowii (Lamiaceae, Lamiales), a narrow endemic of the Western Tian-Shan

Background

Salviakorolkowii (Lamiaceae) has been considered a species of highest conservation priority due to its narrow distribution and isolated taxonomic position. The species has been known from Uzbekistan and, questionably, Kyrgyzstan and treated as endemic to the Western Tian-Shan. Its modern conservation status according to the IUCN Criteria has not been established.

New information

The taxonomic position of Salviakorolkowii is evaluated; the species is treated as the sole member of S.sect.Odontochilus (Pobed.) Sennikov, comb. nov. because of its morphological differences and phylogenetic isolation. The herbarium collections are completely revised and the species is proven to occur mainly in Uzbekistan with a single locality (new country record) in Kazakhstan; its former report from Kyrgyzstan (one locality) is confirmed and documented by herbarium specimens. The species occurrences are mapped and its conservation status is assessed as Vulnerable due to the restricted size and continuous decline of its populations because of the ongoing degradation and destruction of its primary habitat (variegated outcrops) at lower elevations. This study highlights the importance of a thorough revision of herbarium collections in Central Asia for conservation purposes.

The complete chloroplast genome of Salvia liguliloba Y. Z. Sun (Lamiaceae)

Salvia liguliloba Y. Z. Sun is a plant species endemic to the Tianmu Mountains. In this study, we assembled the complete chloroplast genome of S. liguliloba. The chloroplast genome of S. liguliloba was 151,490 bp with quadripartite structure in length, which contained 124 encoded genes, including 79 protein-coding genes, eight ribosomal RNA genes, and 37 transfer RNA genes. Our phylogenetic analysis result based on 54 chloroplast genomes revealed that S. liguliloba was closely related to S. miltiorrhiza according to the current sampling extent in Lamiaceae.

White Sage (Salvia apiana)-a Ritual and Medicinal Plant of the Chaparral: Plant Characteristics in Comparison with Other Salvia Species

Salvia apiana, commonly known as white sage, is an aromatic evergreen subshrub of the chaparral, commonly found in coastal plains in California and Baja California. It has been traditionally used by the Chumash people as a ritual and medicinal plant and used as a calmative, a diuretic, and a remedy for the common cold. However, until recently, relatively little has been known about the composition and biological activity of white sage. Phytochemical studies on S. apiana revealed the presence of substantial amounts of essential oil, accompanied by a variety of triterpenes, C23 terpenoids, diterpenes, and flavonoids. Extracts of the plant have been shown to exhibit antioxidative, antimicrobial, and cytotoxic effects. The influence of white sage constituents on the nervous system, including GABA, opioid, and cannabinoid receptors, has also been documented. The review aimed to compile information on the taxonomy, botany, chemical composition, and biological activities of S. apiana. White sage was compared with other representatives of the genus in terms of chemical composition. The differences and similarities between S. apiana and other sage species were noted and discussed in the context of their therapeutic applications. Reports on ethnomedicinal uses of white sage were confronted with reports on chemistry, bioactivity, and bioavailability of S. apiana constituents. Finally, a critical assessment of the available data was made and perspectives for the use of white sage preparations in modern phytomedicine were discussed.

A Review on the Ethnopharmacology and Phytochemistry of the Neotropical Sages (Salvia Subgenus Calosphace; Lamiaceae) Emphasizing Mexican Species

Salvia is the most diverse genus within the mint family (Lamiaceae), many of its species are well-known due to their medicinal and culinary uses. Most of the ethnopharmacological and phytochemical studies on Salvia are centred on species from the European and Asian clades. However, studies about the most diverse clade, the Neotropical sages (Salvia subgenus Calosphace; 587 spp.), are relatively scarce. This review aims to compile the information on the traditional medicinal uses, pharmacological and phytochemistry properties of the Neotropical sages. To do so, we carried out a comprehensive review of the articles available in different online databases published from the past to 2022 (i.e., PubMed, Scopus, and Web of Science, among others) and summarized the information in tables. To uncover phylogenetic patterns in the distribution of four different groups of metabolites (mono-, sesqui-, di-, and triterpenes), we generated presence-absence matrices and plotted the tip states over a dated phylogeny of Salvia. We found several studies involving Mexican species of Salvia, but only a few about taxa from other diversity centres. The main traditional uses of the Mexican species of Calosphace are medicinal and ceremonial. In traditional medicine 56 species are used to treat diseases from 17 categories according to the WHO, plus cultural-bound syndromes. Pharmacological studies reveal a wide range of biological properties (e.g., antinociceptive, anti-inflammatory, anxiolytic, cytotoxic, and antidiabetic, etc.) found in extracts and isolated compounds of 38 Neotropical sages. From extracts of these species, at least 109 compounds have been isolated, identified and evaluated pharmacologically; 73 of these compounds are clerodanes, 21 abietanes, six flavonoids, five sesquiterpenoids, and four triterpenoids. The most characteristic metabolites found in the Neotropical sages are the diterpenes, particularly clerodanes (e.g., Amarisolide A, Tilifodiolide), that are found almost exclusively in this group. The Neotropical sages are a promising resource in the production of herbal medication, but studies that corroborate the properties that have been attributed to them in traditional medicine are scarce. Research of these metabolites guided by the phylogenies is recommended, since closely related species tend to share the presence of similar compounds and thus similar medicinal properties.

Genetic diversity of the cultivated Salvia miltiorrhiza populations revealed by four intergenic spacers

For better understanding the genetic diversity and phylogeny of the cultivated Salvia miltiorrhiza populations, four intergenic spacer sequences, ETS, psbA-trnH, trnL-trnF, and ycf1-rps15 of the 40 populations collected from China were Polymerase Chain Reaction (PCR) amplified, analyzed both individually and in combination. Haplotype diversity analysis showed that the cultivated S. miltiorrhiza populations had a very rich genetic diversity and an excellent capacity to resist environmental pressure. The best-fit nucleotide substitution models for ETS, psbA-trnH, trnL-trnF, ycf1-rps15, and their combined sequences were HKY+I, T92, T92, T92+G, and T92+G, respectively; the nucleotide conversion frequency in the combined sequences was lower than the transversion, and the relatively high nucleotide substitution frequencies suggests its high genetic variability. Neutral tests showed that the spacer sequences of the populations conform with the neutral evolution model, and there has been no current expansion events occurred. Phylogeny analyses based on both the individual and the combined sequences showed that the 40 populations were clustered in two clades with a very similar topological structure. The discrimination rate of the combined sequence marker is significantly increased to 52.5% (21 populations) over the highest 35% (13 populations) by the single marker of ETS, though still inadequate but a big step forward. Further exploration of more DNA markers is needed. This study for the first time revealed the rich genetic diversity and phylogeny of the currently cultivated S. miltiorrhiza populations in China and provides novel alternative molecular markers for the genetic identification and resources evaluation of the cultivated S. miltiorrhiza populations.

A 2-oxoglutarate-dependent dioxygenase converts dihydrofuran to furan in Salvia diterpenoids

Tanshinone ⅡA (TⅡA), a diterpene quinone with a furan ring, is a bioactive compound found in the medicinal herb redroot sage (Salvia miltiorrhiza Bunge), in which both furan and dihydrofuran analogs are present in abundance. Progress has been made recently in elucidating the tanshinone biosynthetic pathway, including heterocyclization of the dihydrofuran D-ring by cytochrome P450s; however, dehydrogenation of dihydrofuran to furan, a key step of furan ring formation, remains uncharacterized. Here, by differential transcriptome mining, we identified six 2-oxoglutarate-dependent dioxygenase (2-ODD) genes whose expressions corresponded to tanshinone biosynthesis. We showed that Sm2-ODD14 acts as a dehydrogenase catalyzing the furan ring aromatization. In vitro Sm2-ODD14 converted cryptotanshinone to TⅡA and thus was designated TⅡA synthase (SmTⅡAS). Furthermore, SmTⅡAS showed a strict substrate specificity, and repression of SmTⅡAS expression in hairy root by RNAi led to increased accumulation of total dihydrofuran-tanshinones and decreased production of furan-tanshinones. We conclude that SmTⅡAS controls the metabolite flux from dihydrofuran- to furan-tanshinones, which influences medicinal properties of S. miltiorrhiza.

Challenges in Medicinal and Aromatic Plants DNA Barcoding-Lessons from the Lamiaceae

The potential value of DNA barcoding for the identification of medicinal plants and authentication of traded plant materials has been widely recognized; however, a number of challenges remain before DNA methods are fully accepted as an essential quality control method by industry and regulatory authorities. The successes and limitations of conventional DNA barcoding are considered in relation to important members of the Lamiaceae. The mint family (Lamiaceae) contains over one thousand species recorded as having a medicinal use, with many more exploited in food and cosmetics for their aromatic properties. The family is characterized by a diversity of secondary products, most notably the essential oils (EOs) produced in external glandular structures on the aerial parts of the plant that typify well-known plants of the basil (Ocimum), lavender (Lavandula), mint (Mentha), thyme (Thymus), sage (Salvia) and related genera. This complex, species-rich family includes widely cultivated commercial hybrids and endangered wild-harvested traditional medicines, and examples of potential toxic adulterants within the family are explored in detail. The opportunities provided by next generation sequencing technologies to whole plastome barcoding and nuclear genome sequencing are also discussed with relevant examples.

The biology of medicinal resource substitution in Salvia

BACKGROUND

The decrease of wild reserves and the sharp increase of market demand have led to resource substitution, but it is still not clear how to discover medicinal alternative resources. Here we reveal the biology of medicinal resource substitution in the case of Salvia.

METHODS

A hypothesis was put forward that phylogeny and ecology were the main factors which determined alternative species selection. Phylogenetic analysis was performed based on chloroplast genomes. Spatial climatic pattern was assessed through three mathematical models.

RESULTS

Salvia miltiorrhiza and alternative species were mainly located in Clade 3 in topology, and their growth environment was clustered into an independent group 3 inferred from principal component analysis. Correlation and Maxent major climate factor analyses showed that the ecological variations within each lineage were significantly smaller than the overall divergent between any two lineages. Mantel test reconfirmed the inalienability between phylogeny and ecology (P = 0.002). Only the species that are genetically and ecologically related to S. miltiorrhiza can form a cluster with it.

CONCLUSIONS

Phylogenetic relationship and geographical climate work together to determine which species has the potential to be selected as substitutes. Other medicinal plants can learn from this biology towards developing alternative resources.

Sage Insights Into the Phylogeny of Salvia: Dealing With Sources of Discordance Within and Across Genomes

Next-generation sequencing technologies have facilitated new phylogenomic approaches to help clarify previously intractable relationships while simultaneously highlighting the pervasive nature of incongruence within and among genomes that can complicate definitive taxonomic conclusions. Salvia L., with ∼1,000 species, makes up nearly 15% of the species diversity in the mint family and has attracted great interest from biologists across subdisciplines. Despite the great progress that has been achieved in discerning the placement of Salvia within Lamiaceae and in clarifying its infrageneric relationships through plastid, nuclear ribosomal, and nuclear single-copy genes, the incomplete resolution has left open major questions regarding the phylogenetic relationships among and within the subgenera, as well as to what extent the infrageneric relationships differ across genomes. We expanded a previously published anchored hybrid enrichment dataset of 35 exemplars of Salvia to 179 terminals. We also reconstructed nearly complete plastomes for these samples from off-target reads. We used these data to examine the concordance and discordance among the nuclear loci and between the nuclear and plastid genomes in detail, elucidating both broad-scale and species-level relationships within Salvia. We found that despite the widespread gene tree discordance, nuclear phylogenies reconstructed using concatenated, coalescent, and network-based approaches recover a common backbone topology. Moreover, all subgenera, except for Audibertia, are strongly supported as monophyletic in all analyses. The plastome genealogy is largely resolved and is congruent with the nuclear backbone. However, multiple analyses suggest that incomplete lineage sorting does not fully explain the gene tree discordance. Instead, horizontal gene flow has been important in both the deep and more recent history of Salvia. Our results provide a robust species tree of Salvia across phylogenetic scales and genomes. Future comparative analyses in the genus will need to account for the impacts of hybridization/introgression and incomplete lineage sorting in topology and divergence time estimation.

Phylogenomics of Salvia L. subgenus Calosphace (Lamiaceae)

The evolutionary relationships of Salvia have been difficult to estimate. In this study, we used the Next Generation Sequencing method Hyb-Seq to evaluate relationships among 90 Lamiaceae samples, including representatives of Mentheae, Ocimeae, Salvia subgenera Audibertia, Leonia, Salvia, and 69 species of subgenus Calosphace, representing 32 of Epling's sections. A bait set was designed in MarkerMiner using available transcriptome data to enrich 119 variable nuclear loci. Nuclear and chloroplast loci were assembled with hybphylomaker (HPM), followed by coalescent approach analyses for nuclear data (ASTRAL, BEAST) and a concatenated Maximum Likelihood analysis of chloroplast loci. The HPM assembly had an average of 1,314,368 mapped reads for the sample and 527 putative exons. Phylogenetic inferences resolved strongly supported relationships for the deep-level nodes, agreeing with previous hypotheses which assumed that subgenus Audibertia is sister to subgenus Calosphace. Within subgenus Calosphace, we recovered eight monophyletic sections sensu Epling, Cardinalis, Hastatae, Incarnatae, and Uricae in all the analyses (nDNA and cpDNA), Biflorae, Lavanduloideae, and Sigmoideae in nuclear analyses (ASTRAL, BEAST) and Curtiflorae in ASTRAL trees. Network analysis supports deep node relationships, some of the main clades, and recovers reticulation within the core Calosphace. The chloroplast phylogeny resolved deep nodes and four monophyletic Calosphace sections. Placement of S. axillaris is distinct in nuclear evidence and chloroplast, as sister to the rest of the S. subg. Calosphace in chloroplast and a clade with "Hastatae clade" sister to the rest of the subgenus in nuclear evidence. We also tested the monophyly of S. hispanica, S. polystachia, S. purpurea, and S. tiliifolia, including two samples of each, and found that S. hispanica and S. purpurea are monophyletic. Our baits can be used in future studies of Lamiaceae phylogeny to estimate relationships between genera and among species. In this study, we presented a Hyb-Seq phylogeny for complex, recently diverged Salvia, which could be implemented in other Lamiaceae.

Nepetoidin B from Salvia plebeia R. Br. Inhibits Inflammation by Modulating the NF-κB and Nrf2/HO-1 Signaling Pathways in Macrophage Cells

Salvia plebeia has been used to treat a variety of inflammatory diseases, as well as colds and bronchitis. Macrophages have antioxidant defense mechanisms to cope with the intracellular reactive oxygen species (ROS) produced as part of the immune response. The nuclear factor erythroid 2-related factor 2 (Nrf2)/heme oxygenase (HO)-1 pathway in inflamed macrophages is an appealing target due to its protective effect against ROS-induced cell damage. In this study, nepetoidin B (NeB) was first isolated from S. plebeia and identified by nuclear magnetic resonance spectroscopy. NeB reduced pro-inflammatory mediators (nitric oxide and prostaglandin E₂) and cytokines (tumor necrosis factor-α, interleukin (IL)-6, and IL-1β) in LPS-activated RAW 264.7 cells by inhibiting the NF-κB signaling pathway. In the NeB-treated group, catalase and superoxide dismutase levels were significantly higher, and ROS expression decreased. By activating Nrf2 signaling, NeB enhanced HO-1 expression. Furthermore, when the cells were pretreated with tin protoporphyrin (an HO-1 inhibitor), the anti-inflammatory effects of NeB were reduced. Therefore, NeB may activate the Nrf2/ HO-1 pathway. These results reveal the NeB isolated from S. plebeia exerts anti-inflammatory effects by modulating NF-κB signaling and activating the Nrf2/HO-1 pathway in LPS-stimulated RAW 264.7 cells.

Conservation Genomics of Wild Red Sage (Salvia miltiorrhiza) and Its Endangered Relatives in China: Population Structure and Interspecific Relationships Revealed From 2b-RAD Data

Red sage (Salvia miltiorrhiza) is a widely used medicinal plant for treatment of cardiovascular and cerebrovascular diseases. Because of excessive excavation by huge market demand and habitat loss by human activities, the wild population resources of S. miltiorrhiza have reduced drastically in recent years. Meanwhile, population status of two closely related species S. bowleyana and S. paramiltiorrhiza were in a trend of decreasing due to their potential replacement of S. miltiorrhiza. Particularly, S. paramiltiorrhiza was threatened and endemic to a small region in eastern China. However, to date there has been no conservation genetic research reported for wild S. miltiorrhiza population and its endangered relatives. Assess the wild germplasm diversity for S. miltiorrhiza and its related species would provide fundamental genetic background for cultivation and molecular breeding of this medicinally important species. In the present study, we investigated the genetic diversity, population structure, and intra/inter-specific differentiation of S. miltiorrhiza and above two relatives using 2b-RAD genome-wide genotyping method. By investigating 81 individuals of S. miltiorrhiza, 55 individuals of S. bowleyana and 15 individuals of S. paramiltiorrhiza from 23 locations in China, we obtained 23,928 SNPs in total. A comparatively high genetic diversity was observed in S. miltiorrhiza (π = 0.0788, H e = 0.0783 ± 0.0007). The observed and expected heterozygosity in populations of these three species ranged from 0.0297 to 0.1481 and 0.0251 to 0.831, respectively. Two major lineage groups were detected in the examined S. miltiorrhiza populations. The results indicated that Dabie Mountain as a genetic diversity center of S. miltiorrhiza and possible complex inter-specific genetic exchange/hybridization occurred between S. miltiorrhiza and the two relatives. We suggest that strategic conservation and germplasm preservation should be considered not only for wild populations of S. miltiorrhiza, but also for its related S. bowleyana and S. paramiltiorrhiza.

Systematic Placement of the Enigmatic Southeast Asian Genus Paralamium and an Updated Phylogeny of Tribe Pogostemoneae (Lamiaceae Subfamily Lamioideae)

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.

Comparative plastomic analysis and insights into the phylogeny of Salvia (Lamiaceae)

Salvia is the largest genus of Lamiaceae, with almost 1000 species, and has been divided into 11 subgenera. Salvia subg. Glutinaria, native to East Asia, is particularly important because of its potential medicinal value. However, the interspecific relationships of this subgenus have not been resolved and the plastomes of Salvia have rarely been studied. In the current study, we compared plastid genome structure and organization of 19 species of Salvia (14 newly sequenced and 5 previously published). Our comparative analysis showed that all Salvia plastomes examined have a quadripartite structure typical of most angiosperms and contain an identical set of 114 unique genes (80 protein-coding genes, 4 rRNA genes, and 30 tRNA genes). The plastome structure of all Salvia species is highly conserved like other Lamiaceae plastomes. Gene content, gene order, and GC content were highly similar in these plastomes. The inverted repeats/single copy region (IR/SC) boundaries of Salvia are highly conserved, and IR contraction only occurred in two species (Salvia mekongensis and S. rosmarinus). In Salvia, sequence divergence was higher in non-coding regions than in coding regions. We found that using large single copy (LSC) and small single copy regions (SSC) with exclusion of the rapidly evolving sites produced the highest resolution in phylogenetic analysis of Salvia, suggesting that using suitable informative sites to build trees is more conducive in phylogenetic research. This study assembled a powerful matrix data set for studying the phylogeny of Salvia, resolving the interspecific relationship of Salvia subg. Glutinaria. The newly sequenced plastid genomes will also enrich the plastome database of Salvia, providing the scientific basis for the development and utilization of germplasm resources of this large and important genus.

Rediscovery of Pogostemon dielsianus (Lamiaceae, Lamioideae), a rare endemic species from southwestern China, after one century

Pogostemon dielsianus (Lamiaceae) was described in 1913 based on a single gathering from northwestern Yunnan of China collected in 1905, and thereafter no further collections were observed until 2019. We rediscovered the rare endemic species in Lushui County, Yunnan. Molecular phylogenetic analyses based on four cpDNA markers (rbcL, rps16, psbA-trnH, and trnL-trnF) and the nuclear ribosomal internal transcribed spacer (ITS) region confirmed its infrageneric placement within subg. Pogostemon. Based on observations of the rediscovered population of P. dielsianus, we updated its morphological description, provided an illustration, and discussed its distribution. Under IUCN criteria, the species was categorized as "Critically Endangered (CR)".

Metabolomics and DNA-Based Authentication of Two Traditional Asian Medicinal and Aromatic Species of Salvia subg. Perovskia

Subgenus Perovskia of the extended genus of Salvia comprises several Central Asian medicinal and aromatic species, of which S. yangii and S. abrotanoides are the most widespread. These plants are cultivated in Europe as robust ornamentals, and several cultivars are available. However, their medicinal potential remains underutilized because of limited information about their phytochemical and genetic diversity. Thus, we combined an ultra-high performance liquid chromatography quadrupole time of flight mass spectrometry (UHPLC-QTOF-MS) based metabolomics with DNA barcoding approach based on trnH-psbA and ITS2 barcodes to clarify the relationships between these two taxa. Metabolomic analysis demonstrated that aerial parts are more similar than roots and none of the major compounds stand out as distinct. Sugiol in S. yangii leaves and carnosic acid quinone in S. abrotanoides were mostly responsible for their chemical differentiation, whereas in roots the distinction was supported by the presence of five norditerpenoids in S. yangii and two flavonoids and one norditerpenoid in S. abrotanoides. To verify the metabolomics-based differentiation, we performed DNA authentication that revealed S. yangii and S. abrotanoides to be very closely related but separate species. We demonstrated that DNA barcoding coupled with parallel LC-MS profiling constitutes a powerful tool in identification of taxonomically close Salvia species.

An updated tribal classification of Lamiaceae based on plastome phylogenomics

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.

Pollinator shifts, contingent evolution, and evolutionary constraint drive floral disparity in Salvia (Lamiaceae): Evidence from morphometrics and phylogenetic comparative methods

Switches in pollinators have been argued to be key drivers of floral evolution in angiosperms. However, few studies have tested the relationship between floral shape evolution and switches in pollination in large clades. In concert with a dated phylogeny, we present a morphometric analysis of corolla, anther connective, and style shape across 44% of nearly 1000 species of Salvia (Lamiaceae) and test four hypotheses of floral evolution. We demonstrate that floral morphospace of New World (NW) Salvia is largely distinct from that of Old World (OW) Salvia and that these differences are pollinator driven; shifts in floral morphology sometimes mirror shifts in pollinators; anther connectives (key constituents of the Salvia staminal lever) and styles co-evolved from curved to linear shapes following shifts from bee to bird pollination; and morphological differences between NW and OW bee flowers are partly the legacy of constraints imposed by an earlier shift to bird pollination in the NW. The distinctive staminal lever in Salvia is a morphologically diverse structure that has evolved in concert with both the corolla and style, under different pollinator pressures, and in contingent fashion.

Leveraging plastomes for comparative analysis and phylogenomic inference within Scutellarioideae (Lamiaceae)

Scutellaria, or skullcaps, are medicinally important herbs in China, India, Japan, and elsewhere. Though Scutellaria is the second largest and one of the more taxonomically challenging genera within Lamiaceae, few molecular systematic studies have been undertaken within the genus; in part due to a paucity of available informative markers. The lack of informative molecular markers for Scutellaria hinders our ability to accurately and robustly reconstruct phylogenetic relationships, which hampers our understanding of the diversity, phylogeny, and evolutionary history of this cosmopolitan genus. Comparative analyses of 15 plastomes, representing 14 species of subfamily Scutellarioideae, indicate that plastomes within Scutellarioideae contain about 151,000 nucleotides, and possess a typical quadripartite structure. In total, 590 simple sequence repeats, 489 longer repeats, and 16 hyper-variable regions were identified from the 15 plastomes. Phylogenetic relationships among the 14 species representing four of the five genera of Scutellarioideae were resolved with high support values, but the current infrageneric classification of Scutellaria was not supported in all analyses. Complete plastome sequences provide better resolution at an interspecific level than using few to several plastid markers in phylogenetic reconstruction. The data presented here will serve as a foundation to facilitate DNA barcoding, species identification, and systematic research within Scutellaria, which is an important medicinal plant resource worldwide.

Tracking temporal shifts in area, biomes, and pollinators in the radiation of Salvia (sages) across continents: leveraging anchored hybrid enrichment and targeted sequence data

PREMISE OF THE STUDY

A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to diversification across the mega-genus Salvia.

METHODS

A chronogram was developed from a supermatrix of anchored hybrid enrichment genomic data and targeted sequence data for over 500 of the nearly 1000 Salvia species. Ancestral areas and biomes were reconstructed using BioGeoBEARS. Pollinator guilds were scored, ancestral pollinators determined, shifts in pollinator guilds identified, and rates of pollinator switches compared.

KEY RESULTS

A well-resolved phylogenetic backbone of Salvia and updated subgeneric designations are presented. Salvia originated in Southwest Asia in the Oligocene and subsequently dispersed worldwide. Biome shifts are frequent from a likely ancestral lineage utilizing broadleaf and/or coniferous forests and/or arid shrublands. None of the four species diversification shifts are correlated to shifts in biomes. Shifts in pollination system are not correlated to species diversification shifts, except for one hummingbird shift that precedes a major shift in diversification near the crown of New World subgen. Calosphace. Multiple reversals back to bee pollination occurred within this hummingbird clade.

CONCLUSIONS

Salvia diversified extensively in different continents, biomes, and with both bee and bird pollinators. The lack of tight correlation of area, biome, and most pollinator shifts to the four documented species diversification shifts points to other important drivers of speciation in Salvia.

Tracking temporal shifts in area, biomes, and pollinators in the radiation of Salvia (sages) across continents: leveraging anchored hybrid enrichment and targeted sequence data

PREMISE OF THE STUDY

A key question in evolutionary biology is why some clades are more successful by being widespread geographically, biome diverse, or species-rich. To extend understanding of how shifts in area, biomes, and pollinators impact diversification in plants, we examined the relationships of these shifts to diversification across the mega-genus Salvia.

METHODS

A chronogram was developed from a supermatrix of anchored hybrid enrichment genomic data and targeted sequence data for over 500 of the nearly 1000 Salvia species. Ancestral areas and biomes were reconstructed using BioGeoBEARS. Pollinator guilds were scored, ancestral pollinators determined, shifts in pollinator guilds identified, and rates of pollinator switches compared.

KEY RESULTS

A well-resolved phylogenetic backbone of Salvia and updated subgeneric designations are presented. Salvia originated in Southwest Asia in the Oligocene and subsequently dispersed worldwide. Biome shifts are frequent from a likely ancestral lineage utilizing broadleaf and/or coniferous forests and/or arid shrublands. None of the four species diversification shifts are correlated to shifts in biomes. Shifts in pollination system are not correlated to species diversification shifts, except for one hummingbird shift that precedes a major shift in diversification near the crown of New World subgen. Calosphace. Multiple reversals back to bee pollination occurred within this hummingbird clade.

CONCLUSIONS

Salvia diversified extensively in different continents, biomes, and with both bee and bird pollinators. The lack of tight correlation of area, biome, and most pollinator shifts to the four documented species diversification shifts points to other important drivers of speciation in Salvia.

Integrative taxonomy of commercially important deep water penaeoid shrimps from India

The deep water penaeoid shrimp is an important commercial crustacean resource along the Indian coast. The molecular and morphological information of this group from the Indian coast is scarcely known. In this study, we investigated the identification and phylogenetic relationships of the deep water penaeoid shrimps using three mitochondrial (cytochrome oxidase subunit I (COI), cytochrome b, 16S rRNA) genes, which were compared with 54 morphological characters and further used to evaluate character evolution. Our study revealed remarkable molecular divergence (3.3-33.0%) in nine species from three genera of Solenoceridae, four species from three genera of Penaeidae and one species from Aristeidae using COI. Phylogenetic analysis using maximum likelihood and Bayesian approaches revealed that all species from these families are monophyletic. The present analysis revealed the existence of subgroups in the genus Solenocera suggesting the slow reduction of postrostral carina which corresponds to the increase in distributional depth during the evolutionary process which further indicates the origin of the genus in the continental shelf and extending up to the continental slope. In addition, we generated the DNA barcode database involving these species which can help further to investigate the detailed evolution and biogeography of these valuable crustacean resources.