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Hedyotis pubicaulis, a new species from China is described and photographed. It resembles H. uncinella in having herbal habit, tetragonal stem, sessile glomerate inflorescences, and dehiscent capsules, but it can be easily distinguished by having densely pubescent stem, truncate to triangular stipules with 6–14 bristles and only axillary glomerate inflorescence. The molecular phylogenetic analysis revealed that the new species was embedded in the genus Hedyotis. The new species is evaluated as Least Concern according to IUCN Red List Categories and Criteria.

Rubiaceae is the fourth largest and a taxonomically complex family of angiosperms . Many species in this family harbor low reproductive isolation and frequently exhibit inconsistent phenotypic characteristics. Therefore, taxonomic classification and their phylogenetic relationships in the Rubiaceae family is challenging, especially in the genus Leptodermis. Considering the low taxonomic confusion and wide distribution, Leptodermis oblonga is selected as a representative Leptodermis for genome sequencing. The assemblies resulted in 497 Mbp nuclear and 155,100 bp chloroplast genomes , respectively. Using the nuclear genome as a reference, SNPs were called from 37 Leptodermis species or varieties. The phylogenetic tree based on SNPs exhibited high resolution for species delimitation of the complex and well-resolved phylogenetic relationships in the genus. Moreover, 28,987 genes were predicted in the nuclear genome and used for comparative genomics study. As the first chromosomal-level genome of the subfamily Rubioideae in Rubiaceae, it will provide fruitfully evolutionary understanding in the family.

Combretum xylocarpum, a new species from China, is described and illustrated. It is similar to C. acuminatum in leaf shape, spike position, flower structure and hypanthium shape, but obviously different from it by its fewer secondary veins, pale whitish flower petals, ellipsoidal woody fruits with 4 rounded ridges. In addition, the pollen grains of the new species exhibit unique characters comparing to other congeneric allies. Its conservation status is assessed to be Least Concern, according to the IUCN Red List Criteria and Category.

Hedyotis puberulifolia from eastern Guangdong province, China, is described and photographed here. It is clearly different from all other congeneric species by its puberulous stem, leaves, stipules, and thyrsoid inflorescence with monochaisal sub-axes. Phylogenetic analysis revealed that H. puberulifolia is closely related to the sympatric H. tenuipes. It is evaluated as Least Concern according to IUCN Red List Categories and Criteria.

Fenghwaia, a new monotypic genus, along with the new species Fenghwaia gardeniicarpa, is described from Guangdong Province, China. The combined features of inferior ovary, cylindrical drupaceous fruits and orbicular and dorsiventrally-compressed seeds with an elongate and pronounced basal appendage make the new genus significantly different from other genera of the family. In addition, its pollen morphology also showed great similarity to other species of this stenopalynous family. The molecular phylogenetic analysis, based on nuclear ribosomal internal transcribed spacer (ITS) and plastid trnL-F intron spacer (trnL-F) DNA sequence data from the new genus and the other 375 species representing 58 genera of Rhamnaceae, indicates that Fenghwaia is nested within the ‘rhamnoid’ group and sister to the tribe Rhamneae and then both sister to the tribe Maesopsideae. A taxonomic classification key to the ‘rhamnoid’ group is provided, based on morphological characters. A global conservation assessment is also performed and classifies Fenghwaia gardeniicarpa as Near Threatened (NT).

Gyrocheilos taishanense G.T. Wang, Yu Q. Chen & R.J. Wang (Gesneriaceae) from south China is described and illustrated with photographs. It is morphologically similar to G. microtrichum W.T.Wang, but it is distinguished by its glabrous or sparsely hairy pedicels, zygomorphic calyx with hairs in unequal length, and slightly bilobed adaxial corolla lips. Molecular phylogenetic analysis based on nuclear ITS and plastid trnL-F sequences strongly supported this new species as sister to a clade comprising the previously described Gyrocheilos species (100% posterior probability and bootstrap support). The new species is evaluated here as Least Concern (LC) according to the IUCN Red List Categories and Criteria.

Involucrella lithophila from the limestone area of Guangxi, China, is described and illustrated here. It is most similar to Hedyotis kurzii and Involucrella chereevensis in having tetragonal stems, slender pedicels and loculicidally dehiscent capsules, but it differs from the former by its 3–5 (–7)-lobed stipules, heterostylous and white flowers and depressed seeds, and from the latter by its 2–4 secondary leaf veins and heterostylous flowers. The molecular phylogenetic analysis revealed that this new species was embedded in the Involucrella clade and closely related to I. chereevensis. It is evaluated as Least Concern according to IUCN Red List Categories and Criteria.

Mayaca fluviatilis, an aquatic plant belonging to the monogeneric family Mayacaceae, native to tropical America, is reported here for the first time to be naturalized in Guangdong province, China. A morphological description, with detailed photographs, is provided for further taxonomic identification. Its invasive risk is evaluated according to its present propagation tendency.

A new species, Dimetia brevipetiolata R. J. Wang, from Guangxi Zhuang Autonomous Region, China, is described and photographed. Morphologically, it is similar to D. scandens and D. ampliflora with respect to their terete stem, lanceolate and thick papery leaves and compound-cymose inflorescences, but differs in prostrate habit, subsessile leaves, rounded leaf base, nearly glabrous corolla, and indehiscent capsules. The molecular phylogenetic analysis revealed that D. brevipetiolata was embedded in the Dimetia clade and closely related to D. auricularia. It is evaluated as Least Concern according to IUCN Red List Categories and Criteria.

Phosphoenolpyruvate carboxylase (PEPC), as the key enzyme in initial carbon fixation of C4and crassulacean acid mechanism (CAM) pathways, was thought to undergo convergent adaptive changes resulting in the convergent evolution of C4 and CAM photosynthesis in vascular plants. However, the integral evolutionary history and convergence of PEPC in plants remain poorly understood. In the present study, we identified the members of PEPC gene family across green plants with seventeen genomic datasets, found ten conserved motifs and modeled three-dimensional protein structures of 90 plant-type PEPC genes. After reconstructing PEPC gene family tree and reconciled with species tree, we found PEPC genes underwent 71 gene duplication events and 16 gene loss events, which might result from whole-genome duplication events in plants. Based on the phylogenetic tree of the PEPC gene family, we detected four convergent evolution sites of PEPC in C4 species but none in CAM species. The PEPC gene family was ubiquitous and highly conservative in green plants. After originating from gene duplication of ancestral C3-PEPC, C4-PEPC isoforms underwent convergent molecular substitution that might facilitate the convergent evolution of C4 photosynthesis in Angiosperms. However, there was no evidence for convergent molecular evolution of PEPC genes between CAM plants. Our findings help to understand the origin and convergent evolution of C4 and CAM plants and shed light on the adaptation of plants in dry, hot environments.

Dunnia sinensis, a monotypic genus of the Rubiaceae, is an Endangered species endemic to China. Its complete chloroplast genome was determined to be 154,909 bp in length and the GC content was 37.80%. The sequence includes a large single-copy region of 84,894 bp, a small single-copy region of 16,973 bp, and the inverted region of 26,521 bp in length. It contains 130 genes, including 84 protein-coding genes, 37 tRNA genes, and 8 rRNA genes. The ML and BI analyses revealed D. sinensis was closely related to Galium mollugo and Leptodermis scabrida with strong bootstrap values belonging to the subfamily Rubioideae.

Feng Shui woodlands are naturally or artificially formed green areas in southern China. They are precious for maintaining ecosystem balance in modern semiurban environments. However, they are generally small and geographically isolated from each other, and the status of genetic diversity of the plant species within them has been almost neglected. Therefore, we studied the genetic diversity of the endangered Erythrophleum fordii in eight Feng Shui woodlands (a total of 1,061 individuals) in Guangzhou, a large city in southern China, using microsatellites. For comparison, one population with 33 individuals sampled in a nature reserve was also studied. Although our results indicate that significant demographic declines occurred historically in E. fordii, such declines have not resulted in consistent reductions in genetic variation over generations in Feng Shui populations in the recent past, and the levels of genetic variation in these populations were higher than or comparable to the genetic variation of the population in the nature reserve. In addition, our parentage and paternity analyses indicated widespread and potential long‐distance pollen flow within one Feng Shui woodland, indicating the presence of an unbroken pollination network, which would at least partially alleviate the genetic erosion due to habitat fragmentation and the unequal gene contributions of E. fordii parents to their progenies when favorable recruitment habitats are absent under most of the parent trees. Overall, our results suggest that E. fordii in Feng Shui woodlands may not be driven to extinction in the near future. Nevertheless, uncontrolled fast urban development with a lack of awareness of Feng Shui woodlands will cause the local extinction of E. fordii, which has already happened in some Feng Shui woodlands., It is the first report about genetic sustainability of tree species under urbanization and habitat fragmentation in China. The results will be combined with the one of the other regions to give a general conclusion of tree species' genetic health under urbanization and guide not only Feng Shui woodlands conservation but also urban reforestation to balance species conservation and economic developments.

The genus Hedyotis sensu lato was splitted into several genera on basis of morphological and molecular evidences. Under this generic delimitation, seven new taxonomic treatments, including six new synonyms and one new combination, are proposed for the Flora of China. The name Hedyotis tenelliflora that misapplied to Scleromitrion angustifolium is also corrected with morphological comparison.

Hedyotis tonggulingensis is described as a new species from China. It is similar to the sympatric species H. hainanensis, but obviously differs in having tetragonal stems with narrow wings, terminal and axillary inflorescences and the short corolla tubes. The phylogenetic analysis revealed that H. tonggulingensis was closely related to the sympatric species of H. pardifolia and H. yazhouensis but not to H. hainanensis. It was evaluated as Least Concern because of its abundant individuals, little economic use and well protected habitat.

Parainvolucrella R.J. Wang, a new monotypic genus is segregated from Hedyotis-Oldenlandia complex based on the morphological and molecular evidences, along with the new combination of P. scabra (Wall. ex Kurz) M.D.Yuan & R.J.Wang. The new genus is phylogenetically sister to Scleromitrion and has ever been mistaken as a member of Scleromitrion, but its perennial woody herbaceous habit, terminal inflorescence, heterostylous flowers, indehiscent capsules, and microreticulate with smooth muri pollen surface ornamentation make it different from the latter. A key for all the genera of this complex in China is provided as well.

Dryopteris wulingshanensis, a new species growing on limestone in the Wulingshan Mountains, Hunan, China, is described and illustrated. This species is most similar to D. jishouensis and D. gymnophylla on general morphological traits, such as the form of scales, rhizome and sori, but differs by the number of vascular bundles at the base of the petiole, length to width ratio of lamina, stalk length of basal pinnae, division of the lamina, apex form of the pinnule and habitat. Moreover, molecular phylogenetic analysis using the chloroplast rbcL gene suggested that D. wulingshanensis, as the sister group of D. jishouensis, is a monophyletic clade. According to its restricted geographic range, small populations and few individuals, D. wulingshanensis should be considered endangered, according to the IUCN Red List criteria.

Background: Phosphoenolpyruvate carboxylase (PEPC), as the key enzyme in initial carbon fixation of C4 and crassulacean acid mechanism (CAM) pathways, was thought to undergo convergent adaptive changes resulted in the convergent evolution of C4 and CAM photosynthesis in vascular plants. However, the integral evolutionary history and convergence of PEPC in plants remained lack of understanding. Results: In present study, we identified the members of PEPC gene family across green plants with genomic data, found ten conserved motifs and modeled three-dimensional protein structures of 90 plant-type PEPC genes. After reconstructed PEPC gene family tree and reconciled with species tree, we found PEPC genes occurred 71 gene duplications and 16 gene losses, which might result from whole-genome duplication events in plants. Based on the integral phylogenetic tree of PEPC gene family, we detected four convergent evolution sites of PEPC in C4 species but no one in CAM species. Conclusions: PEPC gene family was ubiquitous and highly conservative in green plants. After originated from gene duplication of ancestral C3-PEPC, C4-PEPC isoforms underwent convergent molecular substitution that facilitated the convergent evolution of C4 photosynthesis in Angiosperms, but PEPC gene did not exist molecular convergence corresponded to the multiple independent evolution of CAM photosynthesis. Our findings help to understand the origin and evolution of C4 and CAM pathways and shed new light on the adaptation of plants in drought and high-temperature habitats.

Food-medicine plants play an important role in providing nutrition and treating chronic diseases, especially in many minority communities and developing regions. The coastal region of South China has abundant resources of medicinal plants. A long history of cross-cultural medicinal practices among different minority groups has facilitated the development of a remarkable dietary culture by using food-medicine plants. However, integrative ethnobotanical research on both nutritional and functional properties of the food-medicine plants in this region is still limited. In this study, 27 commonly used wild food-medicine plants were recorded and analyzed from the coastal region of South China. Most of them are good sources for calcium (47.83-1099.89 mg/100 g fresh weight), dietary fiber (3.00-31.87 mg/100 g fresh weight), iron (1.17-24.73 mg/100 g fresh weight), and vitamin C (0.44-68.32 mg/100 g fresh weight). Solanum americanum has the highest average nutritive value and is also considered to be good sources for proteins (7.90 g/100 g fresh weight). Medicinal properties of the studied species can be classified into 8 categories: treatment of the damp-heat syndrome, digestive diseases, urologic diseases, arthropathy, respiratory diseases, gynecological diseases, snake or insect bites, and uses as a tonic. Treating the damp-heat syndrome or expelling warm pathogenic factors is the most commonly used ethnomedicinal practice in the study area. The present study highlights that the local ethnomedicinal practices are deeply influenced by local natural conditions and customs. Food-medicine plants with superior key nutrients have been used regularly in the diet as medicinal food to alleviate common endemic diseases.

Leptodermis is a taxonomically problematic genus, and little information about its palynology was known previously. In order to find taxonomic informative characters for species delimitation and their systematic implications, 105 pollen samples, representing 28 species and four varieties, were observed and analyzed. Phylogenetic inference was also conducted based on six chloroplast fragments from 32 taxa to trace the evolutionary trend of pollen characters in Leptodermis. Results showed that two types of pollen can be identified based on the aperture number and position, viz. zonoaperturate pollen with 3 or 4 colpi situated equatorially and pantoaperturate pollen with 6 to 15 apertures evenly spread over the surface forming a polygonal platelike pattern. Pollen polymorphism was rarely observed in a few Leptodermis species. Pollen dimorphism also occurs in Leptodermis, in which the muri are smooth in pollen from pin flowers whereas have minute granules in pollen from thrum flowers. Phylogenetic mapping demonstrated that each of the nine clades matched well with aperture number and position and the 3-colpate condition was plesiomorphic. In Leptodermis, pantoaperturate grains evolved three times independently and were apomorphic. In addition, the frequent occurrence of pollen polymorphism in some species might be explained by shifts among 3-colpate, 4-colpate, and pantoaperturate pollen grains. The pollen-type mapping to the phylogenetic tree revealed that the aperture number and position could well match different phylogenetic clades, suggesting that pollen morphology could provide useful information for taxonomic and systematic studies in Leptodermis.

Supplemental Material, S_China_Food_Medicine_Plant-Supplementary_materials-revised for Nutritional and Functional Properties of Wild Food-Medicine Plants From the Coastal Region of South China by Yuan Xu, Dan Liang, Gang-Tao Wang, Jun Wen and Rui-Jiang Wang in Journal of Evidence-Based Integrative Medicine

Foonchewia coriacea, a monotypic genus of the Rubiaceae, is endemic to China. Its complete chloroplast genome was determined to be 153,114 bp in length and the GC content was 37.90%. The sequence i...

Leptodermis scabrida complex is one of the important components of genus Leptodermis, which is mainly distributed in the Himalaya Mountains. It includes species of L. gracilis, L. hirsutiflora, L. hirsutiflora var. ciliata, L. kumaonensis, L. pilosa var. acanthoclada and L. scabrida. However, species boundaries and relationships within this complex are unclear based on current morphological and molecular evidence. We sequenced 13 complete chloroplast (cp) genomes representing seven taxa of the complex and two non-Leptodermis scabrida complex taxa. After de novo assembly and annotation, we performed comparative genomic analysis. All cp genomes showed highly conserved structures, and the genome sizes ranged from 154,369 bp to 154,885 bp and possessed the same GC content (37.5%). A total of 113 unique genes were identified in each cp sample, including 79 protein coding genes, 30 tRNAs, and four rRNAs. Repeat sequences and SSRs were detected, showing great similarity among all taxa in this complex. Six highly variable regions, including trnS-trnG, rps2-rpoC2, ndhF, rpl32-ccsA, ccsA-ndhD, and ndhA, were screened as potential molecular markers for phylogenetic reconstruction. Based on a total of 27 complete cp genome sequences, the consistent and robust phylogenetic relationships were firstly constructed and the same species within L. scabrida complex clustered into a group. The divergence time of Leptodermis from ancestral taxa occurred at the middle Eocene, which might be due to geological and climatic changes. The 13 complete cp genome sequences reported will provide new clues for phylogeny elucidation, species identification and evolutionary history speculation of Leptodermis, as well as in Rubiaceae.

Eleutherococcus trifoliatus (L.) S. Y. Hu is a wild edible plant and widely used in the coastal region of South China. Here, we report the complete chloroplast genome of E. trifoliatus. The length ...

Isotopes (Rb Sr, C, O, S, and Pb) were investigated from the Zhenzigou Pb Zn deposit in the Qingchengzi mineral field (QMF) of the North China Craton as an aid to determine the genesis of stratiform Pb Zn deposits in the Liao-Ji Rift. A step-dissolution Rb Sr age of 1798 ± 8 Ma with 206Pb/204Pb ratios of 17.7477–17.8527 were obtained from sphalerite. Sulfur isotopic ratios for pyrite (5–14.4‰), sphalerite (2.4–8.6‰), and galena (− 0.3–8.6‰) from Zhenzigou have a narrower range than those from the host Paleoproterozoic Dashiqiao Formation, and granite in the area. Calcite and limestone from ore and wallrocks at the deposit have similar C and O isotope compositions, with δ13CPDB ranging from − 6.0 to − 2.3‰ and δ18OSMOW from 9.8 to 13.7‰, which are similar to those of carbonatite and the mantle. Comprehensive analysis of the Pb isotopic composition of the sulfide from the Zhenzigou deposit and Pb Zn deposits in adjacent area show that the Pb originated from the upper crust and mixed with Pb from the mantle. Sulfur isotopes from Zhenzigou deposit indicate that the mineralization has a volcanic eruption source. The δ13CPDB and δ18OSMOW values indicate that the CO2 originated from a mixed mantle, marine carbonate and organic source. Combined with the study of regional metallogenic background, this paper proposes that deposition of stratiform Pb Zn mineralization in the QMF began ca. 2052 Ma during development of the Liaoji Rift. The mineralization extended to ca. 1798 Ma prior to deformation associated with the Lvliang Movement, which dismembered the stratiform Pb Zn mineralization. The veined mineralization in the region cross-cuts the stratiform deposits and represents remobilized and redeposited deposits associated with the emplacement of Triassic plutons such as the Xinling and Shuangdinggou granites.

Leptodermis scabrida is an important endemic species in Himalaya-Hengduan Mountains. Here, we report the complete chloroplast genome of L. scabrida. The cp genome was determined to be 154783 bp in length and the GC content was 37.5%. The sequence included a large single copy (LSC) region of 84190 bp, a small single copy (SSC) region of 17183 bp and two separated inverted regions of 26705 bp, respectively. It contained 132 genes, including 84 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. This complete genome of L. scabrida will provide valuable information to resolve the complex phylogeny relationship and to elucidate the mechanism of speciation of Leptodermis, as well as for the phylogenetic studies of Rubiaceae.

Premise of the study Microsatellite markers were developed to facilitate studies of genetic diversity and structure in Glyptostrobus pensilis, a critically endangered and monotypic conifer species. Methods and results Using restriction site-associated DNA sequencing (RAD-Seq), we developed 10 polymorphic and 27 monomorphic microsatellite markers. Polymorphism was characterized using 333 individuals from nine populations. The number of alleles per locus ranged from one to 14 at the population level. The levels of observed and unbiased expected heterozygosities varied from 0.058 to 0.844 and 0.219 to 0.583, respectively. Nine of these 10 polymorphic markers were successfully cross-amplified in Taxodium distichum, the species most closely related to G. pensilis. Conclusions These microsatellite markers can be used to reveal the genetic diversity in existing populations of G. pensilis, enabling its conservation and restoration.

Premise of the Study Microsatellite markers were developed to facilitate studies of genetic diversity and structure in Glyptostrobus pensilis, a critically endangered and monotypic conifer species. Methods and Results Using restriction site–associated DNA sequencing (RAD‐Seq), we developed 10 polymorphic and 27 monomorphic microsatellite markers. Polymorphism was characterized using 333 individuals from nine populations. The number of alleles per locus ranged from one to 14 at the population level. The levels of observed and unbiased expected heterozygosities varied from 0.058 to 0.844 and 0.219 to 0.583, respectively. Nine of these 10 polymorphic markers were successfully cross‐amplified in Taxodium distichum, the species most closely related to G. pensilis. Conclusions These microsatellite markers can be used to reveal the genetic diversity in existing populations of G. pensilis, enabling its conservation and restoration.

A new species of Spiradiclis (Rubiaceae) was found during our field trip to Guangxi, China, and is described here as Spiradiclis longanensis R. J. Wang. This species is readily distinguishable from other prostrate and decumbent species of the genus described previously by dense pubescence all over the plant, 5–20 small flowers per cymose, linear calyx lobes, and tubular corolla. The conservation status of VU was preliminarily assessed according to IUCN categories and criteria.

Two new species, Spiradiclis coriaceifolia R.-J. Wang and S. tonglingensis R.-J. Wang, from China, are described and illustrated. Their palynological characters are described based on SEM observations.

The Dawan Mo-Zn-Fe deposit located in the Northern Taihang Mountains in the middle of the North China Craton (NCC) contains large Mo-dominant deposits. The mineralization of the Dawan Mo-Zn-Fe deposit is associated with the Mesozoic Wanganzhen granitoid complex and is mainly hosted within Archean metamorphic rocks and Proterozoic-Paleozoic dolomites. Rhyolite porphyry and quartz monzonite both occur in the ore field and potassic alteration, strong silicic-phyllic alteration, and propylitic alteration occur from the center of the rhyolite porphyry outward. The Mo mineralization is spacially related to silicic and potassic alteration. The Fe orebody is mainly found in serpentinized skarn in the external contact zone between the quartz monzonite and dolomite. Six samples of molybdenite were collected for Re-Os dating. Results show that the Re-Os model ages range from 136.2 Ma to 138.1 Ma with an isochron age of 138 +/- 2 Ma (MSWD = 1.2). U-Pb zircon ages determined by laser ablation inductively coupled plasma mass spectrometry yield crystallization ages of 141.2 +/- 0.7 (MSWD = 0.38) and 130.7 +/- 0.6 Ma (MSWD = 0.73) for the rhyolite porphyry and quartz monzonite, respectively. The ore-bearing rhyolite porphyry shows higher K2O/Na2O ratios, ranging from 58.0 to 68.7 (wt%), than those of quartz monzonite. All of the rock samples are classified in the shoshonitic series and characterized by enrichment in large ion lithophile elements; depletion in Mg, Fe, Ta, Ni, P, and Y; enrichment in light rare earth elements with high (La/Yb)(n) ratios. Geochronology results indicate that skarn-type Fe mineralization associated with quartz monzonite (130.7 +/- 0.6 Ma) formed eight million years later than Mo and Zn mineralization (138 +/- 2 Ma) in the Dawan deposit. From Re concentrations in molybdenite and previously presented Pb and S isotope data, we conclude that the ore-forming material of the deposit was derived from a crust-mantle mixed source. The porphyry-skarn type Cu-Mo-Zn mineralization around the Wanganzhen complex is related to the primary magmatic activity, and the skarn-type Fe mineralization is formed at the late period magmatism. The Dawan Mo-Zn-Fe porphyry-skarn ores are related to the magmatism that was associated with lithospheric thinning in the NCC.

Isotrema plagiostomum X. X. Zhou & R. J. Wang, a new species of Isotrema (Aristolochiaceae) from Guangdong, south China, is described and illustrated for the first time. It is similar to I. thwaitesii in the morphology of the obliquely truncated calyx limb, but differs by the habit, leaf shape, inflorescence position and splitting extent of calyx limb. It is evaluated as CR according to the IUCN categories and criteria.

The neotropical species Spigelia anthelmia L. was firstly collected from China. Morphological characters are described and photographed in detail for further taxonomic identification. The species has become an invasive species in tropical Asia already, but not dispersed to the local ecosystem in Hainan yet, probably because of the short time of naturalization.

Spiradiclis pengshuiensis Bo Pan & R. J. Wang (Rubiaceae) is described as a new species from Chongqing in SW China. It is morphologically compared with Spiradiclis pauciflora L. Wu & Q. R. Liu because of their similarities in habit, pubescent surface, small leaf laminas and subglobose capsules. Its conservation status is evaluated as “VU” according to the IUCN categories and criteria.

During geological investigations conducted over the past several years, the authors found a group of A-type granites in the middle segment of the Bangonghu–Nujiang suture on the Tibetan plateau. These granitic plutons occur as stocks with exposed areas of less than 1 km 2 and lithologically include biotite granite and granodiorite porphyry, which had intruded into Cretaceous sedimentary rocks. Petrogeochemically, the A-type granites contain high SiO 2 levels varying from 68.62%–75.36 wt.%. Moreover, they contain relatively high Fe 2 O 3 T (0.86–5.39 wt.%) and low Al 2 O 3 (12.76–15.54 wt.%) levels and are weak peraluminous to metaluminous. A trace element N-MORB-normalized spider diagram showed apparent enrichment of the large ion lithophile elements (LILE) Rb, Th, U, K, and Pb with marked depletions of Ba and Sr. The high field strength elements (HFSE) Nb, Ta and Ti were sharply depleted, with relative enrichment of Zr and Hf. These signatures are characteristic of A-type granite. The granite samples had high rare earth element (REE) contents with ∑ REE = 122.37–291.19 ppm. Light REE were rich relative to heavy REE with LREE/HREE = 4.89–9.58. And negative Eu anomalies were sharp with δEu varying from 0.14–0.5 and a mean value of 0.34. Their chondrite-normalized rare earth element distribution patterns appear as gently right-dipping V-types. Zircon U–Pb LAICPMS dating for three granitic plutons yielded weighted mean ages of 109.6 ± 1.4 Ma (MSWD = 3.7), 112.3 ± 0.51 Ma (MSWD = 0.21) and 113.73 ± 0.5 Ma (MSWD = 0.21), indicating that they formed in the late stage of the early Cretaceous epoch. The Nd, Sr and Pb isotopic results showed that the granites were rich in radiogenic isotopes. The 87 Sr/ 86 Sr and I Sr ratios varied from 0.719842–0.786395 and 0.706900–0.710378, respectively. The 143 Nd/ 144 Nd ratios were from 0.512123–0.512392, with relatively large negative e Nd values (− 3.37 to − 10.34). The 206 Pb/ 204 Pb, 207 Pb/ 204 Pb, and 208 Pb/ 204 Pb ratios ranged from 18.703–19.070, 15.680–15.732 and 39.121–39.576, respectively, exhibiting isotopic signatures typical of crustal sources. All of the data demonstrated unanimously that these granites were derived from partial melting of arc basaltic rocks underplated in the lower crust during oceanic crust subduction. The high-temperature heat source for melting of anhydrous basaltic rocks of the lower crust was from upwelling asthenosphere through slab windows formed as a result of slab break-off during post-collisional extension of the orogenic zone.

The new species, Foonchewia guangdongensis R. J. Wang & H. Z. Wen and the new monotypic genus Foonchewia R. J. Wang (Rubioideae, Rubiaceae), are described from eastern Guangdong, China. It is characterized by its subshrub habit, pentamerous and heterostylous flowers, 2-1ocular ovary with many ovules, and apically dehiscent capsules with numerous angulated seeds. Phylogenetic analysis of four chloroplast DNA regions (rbcL, rps16, ndhF, and atpB-rbcL) revealed that the new genus is nested in the Spermacoceae alliance and is sister to Dunnia. Morphological comparison between these two genera indicated that they had few synapomorphies; it was therefore inappropriate to classify the new genus in the existing tribe Dunnieae, and a new tribe, Foonchewieae R. J. Wang, is accordingly proposed.

Ligustrum guangdongense R. J. Wang & H. Z. Wen (Oleaceae), from Guangdong, China, is described and illustrated. The new species is similar to L. punctifolium M. C. Chang and L. morrisonense Kaneh. & Sasaki, based on the small leaf blades and terminal inflorescences. Ligustrum guangdongense differs from L. punctifolium by having sparsely punctate glands on the abaxial leaf blade surface (vs. densely so), a corolla tube longer than the corolla lobes (1.6–1.9:1 vs. 1.1–1.3:1), and stamens that are included within (vs. exserted). Ligustrum guangdongense differs from L. morrisonense by having abaxially punctate leaf blades (vs. not punctate), typically 12 to 28 flowers in an inflorescence (vs. two or three), and a corolla tube that is shorter relative to the corolla lobes. The pollen grains of the new species are subprolate, with tricolpate apertures and a reticulate exine. The IUCN conservation status of L. guangdongense is assessed as Critically Endangered (CR).

A new species, Hedyotis xinyiensis X. Guo & R.J. Wang (Rubiaceae), from the west of the Guangdong province, China, is described and illustrated. It belongs to Hedyotis sect. Diplophragma due to its septicidal dehiscence of mature capsules. The morphological characters that distinguish it from the two similar species, H. consanguinea and H. matthewii, are listed in a table. The ultrastructure of pollen grains, seeds, and leaf epidermis was examined by SEM.

The potential application of DNA barcodes of plastid (matK, trnH–psbA, petD, and rbcL) and nuclear (internal transcribed spacer (ITS) of rDNA) DNA regions was investigated for 25 Hedyotis taxa. The ITS showed the best species discrimination by resolving 23 of the species as exclusive lineages with no shared alleles between any of the 24 distinct species (H. assimilis and H. mellii are not supported as distinct species based on our molecular and morphological data). Conversely, rbcL performed the worst and only resolved 10 of the species as exclusive lineages, and 10 species with shared alleles. Using ITS has the advantage of high PCR amplification success and it provides good intra- and interspecific variation distribution patterns. The most powerful plastid markers were petD and trnH–psbA, but we could amplify and sequence trnH–psbA for only 83% of the accessions sampled. Combination of ITS and petD performed extremely well, with all 24 of the distinct species resolved as exclusive lineages and no shared alleles between any of the distinct species. We therefore recommend ITS, or a combination of ITS and petD, as the standard DNA barcode in Hedyotis, but acknowledge that there are no shared alleles between distinct species for matK and rbcL combined.