Projected impacts of climate change on the habitat of Xerophyta species in Africa.

Climate change poses a serious long-term threat to biodiversity. To effectively reduce biodiversity loss, conservationists need to have a thorough understanding of the preferred habitats of species and the variables that affect their distribution. Therefore, predicting the impact of climate change on species-appropriate habitats may help mitigate the potential threats to biodiversity distribution. Xerophyta, a monocotyledonous genus of the family Velloziaceae is native to mainland Africa, Madagascar, and the Arabian Peninsula. The key drivers of Xerophyta habitat distribution and preference are unknown. Using 308 species occurrence data and eight environmental variables, the MaxEnt model was used to determine the potential distribution of six Xerophyta species in Africa under past, current and future climate change scenarios. The results showed that the models had a good predictive ability (Area Under the Curve and True Skill Statistics values for all SDMs were more than 0.902), indicating high accuracy in forecasting the potential geographic distribution of Xerophyta species. The main bioclimatic variables that impacted potential distributions of most Xerophyta species were mean temperature of the driest quarter (Bio9) and precipitation of the warmest quarter (Bio18). According to our models, tropical Africa has zones of moderate and high suitability for Xerophyta taxa, which is consistent with the majority of documented species localities. The habitat suitability of the existing range of the Xerophyta species varied based on the climate scenario, with most species experiencing a range loss greater than the range gain regardless of the climate scenario. The projected spatiotemporal patterns of Xerophyta species help guide recommendations for conservation efforts.

The genus Balanophora J. R. Forst. & G. Forst. - Its use in traditional medicine, phytochemistry, and pharmacology: A review.

ETHNOPHARMACOLOGICAL RELEVANCE: Natural products, particularly medicinal plants, have been utilized in traditional medicine for millennia to treat various diseases. The genus Balanophora (Balanophoraceae) consists of 23 accepted species. These species are the most controversial flowering plants, with highly reduced morphologies and are found parasitizing on the roots of their host. They have been used in traditional medicine as a remedy for stomach pain, detumescence, uterine prolapse, wounds, syphilis, gonorrhea, treating injuries from falls, and other conditions. However, there is no review of this genus on its traditional uses, phytochemistry, and pharmacology. AIM: The present narrative review discusses the scientific data supporting the traditional uses of Balanophora species. The available information on its botanical properties, traditional uses, chemical contents, pharmacological activities, and toxicity was summarized to help comprehend current research and offer a foundation for future research. MATERIALS AND METHODS: The materials used in combining data on the genus Balanophora comprises online sources such as Web of Science, Google Scholar, Science Direct, and Chinese National Knowledge Infrastructure (CNKI) for Chinese-related materials. World Flora online was used in validating the scientific names of this genus while ChemBio Draw Ultra Version 22.2 software was employed in drawing the phytochemical compounds. RESULTS: Nine Balanophora species including B. harlandii, B. japonica, B. polyandra, B. fungosa, B. fungosa subsp. indica, B. laxiflora, B. abbreviata, B. tobiracola, and B. involucrata have been documented as vital sources of traditional medicines in different parts of Asia. A total of 159 secondary metabolites have been isolated and identified from the ten species of this genus comprising tannins, flavonoids, sterols, lignans, chalcones, terpenes, and phenylpropanoids. Among these compounds, tannins, lignans, terpenoids, chalcones and phenolic acids contribute to the pharmacological activities of the species in this genus with several biological activities both in vitro and in vivo such as anti-inflammatory, anti-oxidant, hypoglycemic activity, cytotoxicity, anti-microbial, melanin synthesis etc. CONCLUSION: This review summarizes the available literature on the traditional uses, pharmacological properties, and phytoconstituents of Balanophora species indicating that they contain fascinating chemical compounds with diverse biological activities. The traditional uses of the species in this genus have been confirmed by scientific data such as antimicrobial, hemostatic effect, gastroprotective activity and others. However, many species in this genus are yet unknown in terms of their botanical uses, chemical composition and biological activities. Thus, more research into the scientific connections between traditional medicinal uses and pharmacological activities, mode of action of the isolated bioactive constituents, and toxicity of other Balanophora species is needed to determine their efficacy and therapeutic potential for safe clinical application.

Ethnobotanical uses, phytochemistry and pharmacology of pantropical genus Zanthoxylum L. (Rutaceae): An update.

ETHNOPHARMACOLOGICAL RELEVANCE: Plants have been used in various parts of the world to treat various diseases. The genus Zanthoxylum L. (Rutaceae) is the second largest genus of this family and comprises approximately 225-549 species distributed in the tropical and temperate regions of the world. Plants of this genus are trees and shrubs with various applications in folklore medicine for food, medicine, construction, and other uses. AIM OF THE REVIEW: The goal of this review is to give an updated data on the ethnobotanical applications, phytochemistry, and pharmacology of the Zanthoxylum species to investigate their medicinal potential and identify research gaps for future research studies. MATERIALS AND METHODS: Data was obtained through a systematic search of published literature and online databases such as Google Scholar, Web of Science, PubMed, Science Direct, and Sci-Finder. The botanical names were confirmed using the World Flora Online and chemical structures were drawn using the ChemBio Draw Ultra Version 14.0 Software. RESULTS: The Zanthoxylum species have a wide use in different parts of the continents as a remedy for various diseases such as digestive diseases, gastrointestinal disorders, venereal diseases, respiratory diseases, rheumatism, bacterial diseases, viral, and other diseases. Various parts of the plant comprising fruits, seeds, twigs, leaves, oils, and stems are administered singly or in the form of decoction, infusion, powder, paste, poultice, juice, or mixed with other medicinal plants to cure the disease. More than 400 secondary metabolites have been isolated and characterized in this genus with various biological activities, which comprise alkaloids, flavonoids, coumarins, lignans, alcohols, fatty acids, amides, sesquiterpenes, monoterpenes, and hydrocarbons. The crude extracts, fractions, and chemical compounds isolated from the genus have demonstrated a wide range of biological activities both in vivo and in vitro, including; anti-cancer, antimicrobial, anti-sickling, hepatoprotective, antipyretic, antitumor, and other pharmacological activities. CONCLUSION: This genus has demonstrated an array of phytoconstituents with therapeutic potential. The ethnobotanical uses of this genus have been confirmed in modern pharmacological research. This genus is a potential source for modern drug discovery and health care products. Further and extensive research is therefore required on the safety approval and therapeutic application of the species of this genus as well as clinical trials and pharmacokinetic studies.

A review on the traditional uses, phytochemistry, and pharmacology of the genus Veronicastrum (Plantaginaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Veronicastrum Heist. ex Fabr. (Plantaginaceae) is a multifunctional plant in China and other parts of the continent. It has traditionally been used in the treatment of ascites, edema, blood stasis, pain relief, chronic nephritis injury, fever, cough, headache, arthritis, dysentery, rheumatism, pleural effusion, liver damage, and other disorders. Although research has confirmed that the genus Veronicastrum contain many active compounds, no review of its traditional uses, phytochemistry or pharmacology has been conducted to date. AIM: This review aims to systematically evaluate the traditional uses, phytochemistry, and pharmacology of the genus Veronicastrum, discuss its medicinal potential, modern scientific research, and the relationship between them, and put forward some suggestions to promote further development and utilization of Veronicastrum. MATERIALS AND METHODS: The traditional uses, phytochemical and pharmacological data related to the genus Veronicastrum from 1955 to date was compiled by surveying the ethnomedicinal books and published papers, and searching the online databases including Google Scholar, China National Knowledge Infrastructure (CNKI), Science Direct, Web of Science and World Flora Online. RESULTS: Species of the genus Veronicastrum are widely used in folkloric medicine and some of their uses have been confirmed in modern pharmacological activities. A total of 89 chemical constituents have been isolated from the genus Veronicastrum, including flavonoids, carbohydrates, iridoids, terpenoids, phytosterols, phenolic acids, and other constituents. Among the compounds isolated, iridoids, flavonoids, and terpenoids are responsible for the biological activities of this genus with significant pharmacological activities both in vitro and in vivo. The extracts and compounds isolated from this genus have been reported to contain a wide range of pharmacological activities such as immunosuppressive, antioxidant, anti-cancer, anti-inflammatory, gastro protective, and antimicrobial activity. CONCLUSION: The genus Veronicastrum is not only a great herbal remedy, but also has numerous bioactive chemicals with potential for new drug discovery. In the literature, phytochemical investigations have been undertaken on five species. Detailed scientific research is still needed to fully understand this genus. Furthermore, its bioactive chemicals' structure-activity connection, in vivo activity, and mechanism of action ought to be investigated further.

Comparative chloroplast genome analysis of Sambucus L. (Viburnaceae): inference for phylogenetic relationships among the closely related Sambucus adnata Wall. ex DC Sambucus javanica Blume.

Sambucus L. is found in the family Viburnaceae (syn. Adoxaceae) and encompasses approximately 29 accepted species. The complex morphology of these species has caused continued confusion concerning their nomenclature, classification, and identification. Despite previous attempts to resolve taxonomic complexities in the Sambucus genus, there are still unclear phylogenetic relationships among several species. In this study, the newly obtained plastome of Sambucus williamsii Hance. as well as the populations of Sambucus canadensis L., Sambucus javanica Blume, and Sambucus adnata Wall. ex DC were sequenced, and their sizes, structural similarity, gene order, gene number, and guanine-cytosine (GC) contents were analyzed. The phylogenetic analyses were conducted using the whole chloroplast genomes and protein-coding genes (PCGs). The findings revealed that the chloroplast genomes of Sambucus species exhibited typical quadripartite double-stranded DNA molecules. Their lengths ranged from 158,012 base pairs (bp) (S. javanica) to 158,716 bp (S. canadensis L). Each genome comprised a pair of inverted repeats (IRs), which separated the large single-copy (LSC) and small single-copy (SSC) regions. In addition, the plastomes contained 132 genes, encompassing 87 protein-coding, 37 tRNA, and four rRNA genes. In the simple sequence repeat (SSR) analysis, A/T mononucleotides had the highest proportion, with the most repetitive sequences observed in S. williamsii. The comparative genome analyses showed high similarities in structure, order, and gene contents. The hypervariable regions in the studied chloroplast genomes were trnT-GGU, trnF-GAA, psaJ, trnL-UAG, ndhF, and ndhE, which may be used as candidate barcodes for species discrimination in Sambucus genus. Phylogenetic analyses supported the monophyly of Sambucus and revealed the separation of S. javanica and S. adnata populations. Sambucus chinensis Lindl. was nested within S. javanica in the same clade, collaborating their conspecific treatment. These outcomes indicate that the chloroplast genome of Sambucus plants is a valuable genetic resource for resolving taxonomic discrepancies at the lower taxonomic levels and can be applied in molecular evolutionary studies.

Ethnobotany, phytochemistry, pharmacology, and conservation of the genus Calanthe R. Br. (Orchidaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: The Genus Calanthe (family Orchidaceae) consists of more than 207 species distributed in both tropical and subtropical regions. In traditional medicine, Calanthe species provide remedies against various conditions such as arthritis, rheumatism, traumatic injuries, snake-bites, abdominal discomfort, nose bleeding, common colds, ulcers, chronic coughs, and others. Some species are also used as aphrodisiacs, tonics, and as pain relievers on joints and toothaches. AIM OF THE REVIEW: This review provides comprehensive information on the herbal uses, chemical components, pharmacological activities, and conservation of Calanthe, which might be useful in the future development of potent herbal medicines and facilitate the enactment of better conservation strategies. MATERIALS AND METHODS: Relevant information was obtained from online databases including SCI-Finder, Google Scholar, Web of Science, Science Direct, PubMed, Springer, IOP Science, and other web sources such as PubChem, The Plant List, and World Flora Online. Books, Ph.D. and MSc dissertations were used for unpublished literature. Information from Chinese literature was obtained from the CNKI database. RESULTS: In total, 19 species of the genus Calanthe have been reported to be used in traditional medicine in different countries of Asia. A total of 265 chemical compounds from different chemical classes including, alkaloids, terpenoids, phenolic compounds and phenolic derivatives, phenanthrenes, and others, have been identified from Calanthe species. Calanquinone A isolated from C. arisanensis has been reported to exhibit antitumor activity against six malignant cell lines. Other bioactive compounds from Calanthe with pharmacological activity include phenanthrenes, phenanthrenequinones, 6'-O-ß-D-apiofuranosylindican, 4H-Pyran-4one, 2, 3-dihydro-3,5 dihydroxy-6-methyl, and calanthoside. These compounds exhibit valuable biological properties such as hair restoration, anticancer activity, anti-inflammatory and antiarthritic activity, antidiabetic and hepatoprotective potency, antiplatelet aggregation action, and antibacterial and antifungal activities. Some Calanthe species, including C. ecallosa and C. yuana, are endangered in the IUCN red list. The high risk of extinction is attributed to illegal trade and unsustainable harvesting and utilization. CONCLUSIONS: This review summarizes the herbal uses, chemical components, biological activity, and conservation of Calanthe. The pharmacological studies on this genus are limited; thus, extensive research on the toxicology, pharmaceutical standardization, and mechanism of action of the isolated bioactive compounds are needed. Since some species of Calanthe are listed as endangered, stringent guidelines on trade, collection, and sustainable utilization of medicinal orchids should be set up to facilitate the conservation of these species.

Comparative Genomics, Phylogenetics, Biogeography, and Effects of Climate Change on Toddalia asiatica (L.) Lam. (Rutaceae) from Africa and Asia.

In the present study, two samples of Toddalia asiatica species, both collected from Kenya, were sequenced and comparison of their genome structures carried out with T. asiatica species from China, available in the NCBI database. The genome size of both species from Africa was 158, 508 base pairs, which was slightly larger, compared to the reference genome of T. asiatica from Asia (158, 434 bp). The number of genes was 113 for both species from Africa, consisting of 79 protein-coding genes, 30 transfer RNA (tRNA) genes, and 4 ribosomal RNA (rRNA) genes. Toddalia asiatica from Asia had 115 genes with 81 protein-coding genes, 30 transfer RNA (tRNA) genes, and 4 ribosomal RNA (rRNA) genes. Both species compared displayed high similarity in gene arrangement. The gene number, orientation, and order were highly conserved. The IR/SC boundary structures were the same in all chloroplast genomes. A comparison of pairwise sequences indicated that the three regions (trnH-psbA, rpoB, and ycf1) were more divergent and can be useful in developing effective genetic markers. Phylogenetic analyses of the complete cp genomes and 79 protein-coding genes indicated that the Toddalia species collected from Africa were sister to T. asiatica collected from Asia. Both species formed a sister clade to the Southwest Pacific and East Asian species of Zanthoxylum. These results supported the previous studies of merging the genus Toddalia with Zanthoxylum and taxonomic change of Toddalia asiatica to Zanthoxylum asiaticum, which should also apply for the African species of Toddalia. Biogeographic results demonstrated that the two samples of Toddalia species from Africa diverged from T. asiatica from Asia (3.422 Mya, 95% HPD). These results supported an Asian origin of Toddalia species and later dispersal to Africa and Madagascar. The maxent model analysis showed that Asia would have an expansion of favorable areas for Toddalia species in the future. In Africa, there will be contraction and expansion of the favorable areas for the species. The availability of these cp genomes will provide valuable genetic resources for further population genetics and biogeographic studies of these species. However, more T. asiatica species collected from a wide geographical range are required.

Traditional Uses, Phytochemistry, and Pharmacological Properties of the Genus Blechnum-A Narrative Review.

Blechnum L. is a genus belonging to the Blechnaceae family with 236 accepted species that grow in intertropical, subtropical, and southern temperate regions. Several species of the genus have long been used in folk medicines to treat a broad spectrum of ailments, including typhoid, urinary infections, influenza, wounds, pulmonary complaints, blisters, boils, and antihelmintic-related complications. So far, about 91 chemical compounds have been isolated from different parts of 20 Blechnum species. Among these metabolites, phenolic compounds, sterols, and fatty acids are the main constituents. Modern pharmacological investigations revealed several isolated compounds and extracts to exhibit exceptional biological properties including the antioxidant, antimicrobial, anti-inflammatory, anticancer, insecticidal, antitrematocidal and wound healing. In various tests, both quercetin-7',3',4'-trimethoxy and phytol metabolites showed potential antioxidant and antitrematocidal properties, while ponasterone exhibited insecticidal activity. Despite having a broad range of traditional medicinal benefits and biological properties, understanding the scientific connotations based on the available data is still challenging. This article presents a comprehensive review of the traditional uses, phytochemical compounds, and pharmacological aspects of the Blechnum species.

A review on ethnobotany, phytochemistry, and pharmacology of the genus Didymocarpus wall. (Gesneriaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Medicinal plants have been extensively used to treat various illnesses since the dawn of civilization. The genus Didymorcapus Wall. comprises 100 species widely distributed in the tropical regions of Asia, with a few found scattered in Africa and Australia. Species in this genus have long been used in folk medicine to treat various illnesses, including wounds, kidney stones, inflammations, asthma, flu, eczema, dysentery, fractures, colic etc. Some species have applications as weight loss agents, laxatives, and protective medication after childbirth. AIM: To provide comprehensive information on the current knowledge of the ethnobotanical uses, phytochemical compounds, pharmacological applications, and toxicology of genus Didymocarpus to reveal its therapeutic potential, offering insights into future research opportunities. MATERIALS AND METHODS: Data were systematically obtained from books and online databases such as PubMed, Web of Science, Scopus, Sci Finder, Google Scholar, Science direct, ACS Publications, Elsevier, Wiley Online Library. RESULTS: Seventeen Didymocarpus species have applications in traditional medicine in different Asian countries. A total of 166 compounds have been isolated from the genus Didymocarpus including terpenoids, flavonoids, phenolic compounds, fatty acids, chalcones, steroids, and others. Among these constituents, terpenoids, flavonoids, chalcones, and phenolics are the significant contributors to pharmacological activities of the genus Didymocarpus, possessing wide-reaching biological activities both in vivo and in vitro. The crude extracts and isolated phytochemical compounds from this genus have been shown to exhibit various pharmacological activities, including antiurolithiatic, nephro-protective, antimicrobial, anticancer, antidiabetic, cytotoxic, wound healing, and antioxidant activities. CONCLUSIONS: Traditional uses and scientific evaluation of Didymocarpus indicate that Didymocarpus pedicellata is one of the most widely used species in some parts of the world. Although substantial progress on the chemical and pharmacological properties of Didymocarpus species has been made, further studies on the pharmacology and toxicology of these species are needed to ensure safety, efficacy, and quality. Also, further research on the structure-activity relationship of some of the isolated phytocompounds may improve their biological potency and scientific exploitation of traditional uses of the Didymocarpus taxa.

Ethnobotany, phytochemistry, pharmacology, and toxicology of the genus Sambucus L. (Viburnaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: The genus Sambucus L. (Viburnaceae) consists of about 29 recognized species distributed in all regions of the world except the extremely cold and desert areas. Some species have been used as traditional medicines to treat various disorders such as bone fractures, rheumatism, diabetes, respiratory and pulmonary disorders, skin diseases, inflammatory ailments, diarrhea, and others. However, the currently available data on traditional and pharmacological uses have not been comprehensively reviewed. STUDY AIM: The present review is designed to provide information on the ethnobotanical uses, phytochemistry, toxicity, and the known biological properties of Sambucus, to understand their connotations and provide a scientific basis and gaps for further research. MATERIALS AND METHODS: The information was obtained from different bibliographic databases, Google Scholar, Springer Link, Web of Science, PubMed, and Science Direct along with other literature sources such as dissertation before August 2021. The scientific names were validated using The Plant List and World Flora Online websites. RESULTS: Twelve Sambucus species were found to be frequently mentioned in ethnomedical uses recorded in China, Korea, Turkey, Iran, and other countries. Traditionally, they have been used as remedies to numerous health complications among others, bone fractures and rheumatism, diabetes, wounds, inflammatory diseases, diarrhea, menstrual pains, respiratory and pulmonary complaints, skin disorders, headaches, snakebites, and urinary tract infections. To date, only eleven species have been studied for their chemical compounds and a total of 425 bioactive constituents, including phenolic compounds, terpenoids, fatty acids, cyanogenic glycosides, phytosterols, lectins, organic acids, alkaloid, coumarin, anthraquinone, and others have been reported. The crude extracts and the isolated chemical constituents exhibited diverse outstanding pharmacological activities including antioxidant, antimicrobial, antidiabetic, anti-inflammatory, antidepressant, analgesic, anti-giardial, immunomodulatory, scolicidal, anti-ulcerogenic, antiradical, bone-protective, anti-glycemic, antiosteoporotic, hypolipidemic, anti-glycation, and wound-healing properties. CONCLUSION: This study summarized and scrutinized the data on traditional uses, pharmacological activities, phytochemicals, and toxicity of Sambucus species, which indicate they have interesting chemical compounds with diverse biological activities. Many traditional uses of some species from this genus have now been confirmed by pharmacological activities, such as antioxidant, antimicrobial, bone-protective, wound healing, anti-inflammatory, and analgesic properties. However, the currently available data has several gaps in understanding the traditional uses of all Sambucus species. Thus, we strongly recommend further investigations into the scientific connotations between traditional medicinal uses and pharmacological activities, mode of action of the isolated bioactive constituents, and toxicity of other Sambucus species to unravel their efficacy and therapeutic potential for safe clinical application. The current extensive study avails valuable information on therapeutic use of Sambucus species and paves way for further investigations of other useful species, as well as drug discovery.

Traditional medicinal uses, pharmacology, phytochemistry, and distribution of the Genus Fagaropsis (Rutaceae).

ETHNOPHARMACOLOGICAL RELEVANCE: Genus Fagaropsis belonging to the Rutaceae family, is widely distributed in Africa. The various parts of the species in this genus are used in traditional herbal medicine in different parts of the continent for the treatment of malaria, intestinal disorders, cancer, respiratory diseases, and other ailments. AIM OF THE STUDY: This study provides a comprehensive and updated review on the ethnobotanical uses, phytochemistry, and pharmacology of Fagaropsis species and highlights possible research gaps for further research opportunities, which will be important in the development of new therapeutic drugs. MATERIALS AND METHODS: The data was retrieved using ethnobotanical books, published articles, electronic sources, and scientific databases such as Google Scholar, Plants of the World, The Plant List, Scopus, Wiley, Web of Science, PubMed, Science direct, and Sci-Finder. Various key search words Fagaropsis, pharmacological activities, phytochemistry, and ethnobotanical uses were used in the detailed study survey. RESULTS: Fagaropsis species are used traditionally to treat a wide range of infections such as respiratory diseases, cancer, malaria, intestinal diseases, and ethnoveterinary. Phytochemical investigations indicated 18 phytoconstituents that have been isolated as the main compounds in this genus; triterpenoids (limonoids, norhopane, and norneohopane derivatives), alkaloids, and essential oils. Few in vitro and in vivo pharmacological activities have been analyzed in this genus. They indicated that the extracts and pure compounds contained anti-inflammatory, antiplasmodial, anti-cancer, anti-bacterial, anti-fungal, and insecticidal activities. The phytochemical compounds that may be responsible for these activities are flavonoids, terpenoids, and alkaloids. CONCLUSION: The ethnobotanical values, phytochemistry, and pharmacology discussed in this review paper showed that Fagaropsis species contain different compounds possessing a wide range of biological activities, and they have high medicinal value that is significant in treating different types of diseases. Phytochemical analyses have been performed on two species (F. angolensis and F. glabra) in the literature. More scientific research analyses are still required to explore this genus. In addition, the majority of the currently available bioactivity-related analyses were applied to crude extracts. Thus, further research studies are important to reveal the links between ethnobotanical uses and bioactivity in the future.

Analysis of the Complete Plastomes of 31 Species of Hoya Group: Insights Into Their Comparative Genomics and Phylogenetic Relationships.

Hoya is a genus in Apocynaceae-Asclepiadoideae, known for its showy wax flowers, making it a popular ornamental plant. However, phylogenetic relationships among most Hoya species are not yet fully resolved. In this study, we sequenced 31 plastomes of Hoya group species using genome skimming data and carried out multiple analyses to understand genome variation to resolve the phylogenetic positions of some newly sequenced Chinese endemic species. We also screened possible hotspots, trnT-trnL-trnF, psba-trnH, and trnG-UCC, ndhF, ycf1, matK, rps16, and accD genes that could be used as molecular markers for DNA barcoding and species identification. Using maximum likelihood (ML) and Bayesian Inference (BI), a species phylogeny was constructed. The newly assembled plastomes genomes showed the quasi-tripartite structure characteristic for Hoya and Dischidia with a reduced small single copy (SSC) and extremely enlarged inverted repeats (IR). The lengths ranged from 175,404 bp in Hoya lacunosa to 179,069 bp in H. ariadna. The large single copy (LSC) regions ranged from 80,795 bp (Hoya liangii) to 92,072 bp (Hoya_sp2_ZCF6006). The massively expanded IR regions were relatively conserved in length, with the small single-copy region reduced to a single gene, ndhF. We identified 235 long dispersed repeats (LDRs) and ten highly divergent hotspots in the 31 Hoya plastomes, which can be used as DNA barcodes for species identification. The phylogeny supports Clemensiella as a distinct genus. Hoya ignorata is resolved as a relative to Clade VI species. This study discloses the advantages of using Plastome genome data to study phylogenetic relationships.