Species Complex Research Articles

Diversity of Colletotrichum species causing cherry postharvest anthracnose in China

Cherry postharvest anthracnose (CPA) is an important fungal disease that endangers cherry production. To characterize the pathogen diversity, 43 Colletotrichum isolates were isolated from 175 cherry fruits. The multi-locus phylogenetic analysis (ACT, CAL, CHS-1, GAPDH, HIS3, ITS, TUB2) revealed that strains of the C. gloeosporioides species complex (CGSC) associated with CPA included C. aenigma, C. fructicola, C. gloeosporioides, C. siamense, and strains of the C. acutatum species complex (CASC) included C. fioriniae, C. godetiae, C. salicis. There were significant differences in biological characteristics between CGSC and CASC. The mycelium growth rate, sporulation and conidial germination ability of CGSC was significantly higher than that of CASC. However, CASC was more adaptable to low temperatures. CGSC was more pathogenic than CASC toward cherry fruits. On other tested hosts, all species showed pathogenicity only on wounded condition and the pathogenicity of CGSC and CASC to other host fruits was significantly different too. C. aenigma and C. siamense exhibited significantly higher pathogenicity towards grapes and blueberries compared to C. gloeosporioides and C. fioriniae, while the pathogenicity to cherry tomatoes was reversed. In general, CGSC was more pathogenic than CASC to testes hosts. Our results showed that there were seven species of two species complex of Colletotrichum responsible for CPA in China, and the biological characteristics and pathogenicity of different species were significantly different.

Taxonomic revision of the genus Sarcosphaera (Ascomycota: Pezizales) in Europe and North America revealed unexpected diversity

Sarcosphaera (Ascomycota: Pezizales) is a genus of rare spring fungi, currently encompassing a single species, S. coronaria, which is red-listed in many European countries. The genus is characterized by large bright-colored fruit-bodies and high arsenic content. This study investigates the genetic diversity across Europe and North America. Using integrated molecular techniques, including ITS and 28S rDNA sequencing, we aimed to resolve the taxonomic ambiguities and assess their arsenic hyperaccumulation capabilities, a rare trait among fungi. We identified the presence of two species in the Western Palearctic (S. coronaria, S. crassa) and at least 12 additional lineages in North America, indicating a more complex taxonomic structure than previously recognized. To consolidate the taxonomy and nomenclature of these fungi, we selected reference specimens for S. coronaria and S. crassa and discussed their morphological and ecological differences. Two genera, Caulocarpa (C. montana) and Hydnotryopsis (H. setchellii), a genus comprising hypogeous fungi, are newly placed in the genus Sarcosphaera. Sarcosphaera is thus another genus where the rapid evolution of hypogeous forms from their above-ground ancestors took place. Furthermore, two new Sarcosphaera species, S. columbiana and S. pacifica, are described from the Pacific Northwest. Investigation of arsenic content of Sarcosphaera species revealed that arsenic mass fractions in ascocarps vary significantly between species and even within species across different geographical locations. Our findings have important implications for the taxonomy and conservation of the S. coronaria species complex and also point to future directions for further research in the taxonomy, geomycology, and toxicology of this group of fungi.

DNA barcode library of Portuguese water mites, with the descriptions of two new species (Acari, Hydrachnidia)

This study presents the first results from the analysis of water mites collected in Portugal as part of the Biodiversity Genomics Europe project. 307 COI DNA barcodes clustered into 75 BINs are provided, with 38 BINs being unique and deposited for the first time in the Barcode of Life Data Systems (BOLD). 65 species have been identified, of which 36 are new to the water mite fauna of Portugal. Two species, Torrenticola soniae Pešić, sp. nov. and T. elisabethae Pešić, sp. nov. (Torrenticolidae), are described as new to science. 47% of the water mite species currently known from Portugal now have reference barcodes in BOLD. High intraspecific distances were recorded for some species, suggesting the presence of cryptic diversity and species complexes that needs further study. Our results improve the DNA barcode reference database for Portuguese water mites, enhancing species identification accuracy and stimulating future investigation.

Phylogenetic evaluation and haplotype mapping of phytoplasma disease in sesame: insights into leafhopper-mediated disease transmission through molecular investigation

The predominance of leafhopper species like Orosius albicinctus, Hishimonus phycitis, and Amrasca biguttula biguttula indeed poses a significant threat to sesame production in India and globally. This disease is a major challenge for sesame farming, as it can lead to yield reductions of up to 95%. The current study examined phytoplasma and leafhoppers in sesame and analyzed the phylogenetic differences in the phyllody phytoplasma. The identification of both 16Sr group I and group II phytoplasma isolates, along with the discovery of the 16SrI-B group reported for the first time in Tamil Nadu, represents a significant advancement in our understanding of phytoplasma diversity in the region. The utilization of virtual RFLP analysis in sequencing the sesame phyllody phytoplasma highlights the importance of molecular techniques in characterizing the phytoplasma. Leafhoppers in sesame were a co-occurring species complex of O. albicinctus, H. phycitis, and A. bigutulla bigutulla. The leafhoppers were identified using species-specific taxonomical traits, and a mtCOI gene-based genetic study confirmed the species. In disease transmission efficiency studies in the greenhouse, O. albicinctus transmitted phyllody at a rate ranging from 7.8% to 84%, while H. phycitis transmitted phyllody at a rate of 5.2% to 74%. Both of these species showed the highest transmission efficiency in the combination of three insects per plant with five days of acquisition feeding and one day of inoculation feeding. A comprehensive understanding of leafhopper-phytoplasma interactions through molecular studies supports effective monitoring, early detection, and the development of integrated pest management strategies.

DNA sequencing of topotypes helps delineate species distributions in the Ischnocnema verrucosa complex (Anura, Brachycephalidae)

As many new evolutionary lineages are being discovered and formally named, sequencing topotypes when holotypes are not available becomes essential for taxonomy. This study uses a DNA-taxonomy approach to sequence new populations of the Ischnocnema verrucosa species complex (Brazilian Wart Frogs) from different locations, including, for the first time, individuals from the type localities. Phylogenetic analysis of the mitochondrial 16S gene recovered a monophyletic Ischnocnema verrucosa species series composed of three main clades. The most recent common ancestor was estimated to be 33.76 million years ago, and diversification within the three main clades occurred primarily during the Miocene. We delimited eight species-level lineages with high levels of sequence divergence (7% to 16%). Our study highlights the importance of DNA taxonomy and the necessity of protecting and sequencing topotypes in taxonomic studies. Our study also contributes to the conservation and understanding of the genus Ischnocnema and the biodiversity of the Brazilian Atlantic Forest region.

High Prevalence of Sarcocystis in a Collapsed Black Rat (Rattus rattus) Population from the Florida Keys.

We collected and screened black rats (Rattus rattus) in Key Largo, Florida, USA, to determine the potential role of disease or parasites in the collapse of the local population. Rats appeared healthy, but 94% (n=15/16) tested positive for Sarcocystis sp. The partial 18S rRNA gene sequence was 98.7-99.7% similar to a strain of Sarcocystis zuoi that is now considered a strain of the newly described Sarcocystis kani within the larger S. zuoi species complex that contains numerous new species. These Sarcocystis spp. use Asian snakes as definitive hosts and rodents, shrews, or tree shrews as intermediate hosts. Pythons are the definitive host for several Sarcocystis spp. in Asia, including a related parasite (Sarcocystis singaporensis) that has been used as a biologic control agent for Rattus spp. in southeast Asia. It is probable that increasing numbers of invasive Burmese pythons (Python bivittatus) in the Florida Keys are contributing to the spread of this parasite in addition to imposing predation pressure on both rodents and native snakes. As such, further surveillance and molecular and morphologic characterization of parasites from rodents and snakes in south Florida should be prioritized.

Oceanic boundaries in the western Atlantic delimitate novel lineages in the tanaidacean Chondrochelia dubia (Tanaidacea: Leptocheliidae) species complex

Oceanic boundaries in the western Atlantic delimitate novel lineages in the tanaidacean Chondrochelia dubia (Tanaidacea: Leptocheliidae) species complex

First report of leaf spot on Gleditsia sinensis caused by Colletotrichum gloeosporioides in China.

Gleditsia sinensis Lam (Lamarck et al., 1788) is an endemic species widely distributed in China. In Sep. 2022, leaf spot symptoms were observed on G. sinensis in Xuhui district (31◦9'16''N, 121◦26'36''E), Shanghai, China, with an incidence rate of 55% in the examination of 9 trees. The leaves showed typical symptoms of anthracnose with irregular gray-brown spots and sunken areas. For isolation, 5 × 5 mm sections were cut from the lesion edge of 20 infected leaves collected from 2 trees. The surface of the sections was sterilized by immersion in 75% ethanol for 30 s, followed by 5% NaClO for 1 min, rinsed three times with sterile water, and dried on sterile filter paper. These sections were placed on PDA plates incubated at 25°C in darkness. Eighteen isolates with similar colony morphology were obtained and purified by single spore culturing. Two isolates (YKY2301, 2302) from separate trees were further tested. On the 6th day, the colonies had a diameter of 7.6 to 8.4 cm and appeared white to gray-white with aerial hyphae. The colony's central part exhibited an orange hue due to the conidia accumulation, while the undersides displayed an orange-yellow color. The hyphae were hyaline and smooth, with septa and branches, and the conidia were cylindrical with blunt to slightly rounded ends, measuring 13.1 to 18.8 (average 15.9) μm× 4.0 to 6.6 (average 5.4) μm (n=184). From conidia germinated on glass slides, the appressoria measured 5.5 to 6.3 μm ×4.9 to 5.1 μm (n=50) and were nearly spherical or elliptical in shape. These characteristics matched those of the Colletotrichum gloeosporioides species complex (Cannon et al., 2012; Weir et al., 2012). For molecular identification, the genomic DNA was extracted using a modified CTAB method (Luo et al., 2012). Gene fragments including ITS (PP125667, PP125668), GAPDH (PP153428, PP153429), ACT (PP153424, PP153425), TUB2(PP153917, PP190256), and ApMAT (PP153426, PP153427) were obtained by PCR using universal primers (Huang et al., 2022) and sequenced. The sequences exhibited 98.19% to 99.82% identity with the corresponding gene of the type strain C. gloeosporioides IMI356878 (JX010152, JX010056, JX009531, JX010445, JQ807843) in NCBI BLAST. A multilocus Maximum likelihood phylogenetic tree was constructed based on concatenated the five genes by PhyloSuite. It showed that YKY2301, 2302 were on the same branch with C. gloeosporioides. Based on these results, the isolates were identified as C. gloeosporioides. Pathogenicity tests were conducted by mycelial and conidia inoculation. 5 mm mycelial or blank agar plugs were inoculated onto the leaves of 2 healthy trees in a garden (25 to 30 °C), with and without wounds made by toothpick pricking (n≥3 per group). All mycelial inoculated leaves showed leaf spots on the 6th day. Three healthy 2-year-old seedlings were inoculated with either conidia (108 conidia/ml) or water by leaf spray, and maintained in a climate chamber (27 °C, 80% humidity). Inoculated seedlings showed necrotic leaf spots on day 14, and wilted within 3 weeks. The controls in all tests remained asymptomatic. The pathogen has been re-isolated and confirmed by sequencing, thus fulfilling Koch's postulates. This is the first report of leaf spots caused by C. gloeosporioides on G. sinensis in the world. As illustrated by the example of legume pod infection (Gerusa et al., 2019), it poses a potential threat to the fruits of G. sinensis, despite currently only affecting their ornamental value. This report provides basic information for future research.

Prevalence of <i>Wuchereria bancrofti</i> and <i>Plasmodium Spp.</i> infection in <i>Anopheles</i> mosquitoes and human blood sampled from Matayos in Busia County, Western Kenya

INTRODUCTION Lymphatic filariasis and malaria are mosquito-borne diseases and are co-endemic in coastal Kenya. We evaluated the occurrence of co-infections with Wuchereria bancrofti and Plasmodium falciparum, the causative agents of Lymphatic filariasis and malaria, respectively, in humans and known Anopheles vectors from Matayos constituency, Busia County, western Kenya. MATERIALS AND METHODS The samples were collected purposively based on clinical case reports. Members of the An. gambiae and An. funestus species complexes present and the presence of W. bancrofti and P. falciparum were detected using Polymerase Chain Reaction (PCR). Positive PCR amplicons were purified and Sanger sequenced. RESULTS In this study, 292 Anopheles mosquitoes were analyzed, and 288 of these (98.63%) were successfully identified by PCR. The majority of mosquitoes identified belonged to the An. funestus complex (85.76%) while An. gambiae complex mosquitoes comprised 14.24%. Two W. bancrofti infections were detected in the mosquitoes, one each in An. leesoni and An. funestus s.s. with an infection rate of 0.46% and 4.17% respectively. No P. falciparum was detected in the mosquito or human blood samples and only 2 blood samples (2.17%) were positive for W. bancrofti. Phylogenetic analysis based on the sequenced 18S rRNA gene showed that all W. bancrofti sequences from this study shared a close relationship with W. bancrofti sequences distributed in other regions. No case of co-infection of P. falciparum and W. bancrofti was found in the mosquito or blood samples analyzed. CONCLUSION This study confirms the presence of W. bancrofti infection in the human population and mosquito vectors in Matayos. The study also indicated that the majority of Anopheles mosquitoes from the study area belong to An. funestus complex. This study recommends additional screening before Mass Drug Administration, and that mosquito control programs be strengthened in the study area.

Karyotype diversity of Polybia (gr. occidentalis) species complex (Hymenoptera: Vespidae): Taxonomic and evolutionary implications

AbstractPolybia is a common wasp genus found in most of South America. Polybia (gr. occidentalis) encompasses several species that are difficult to identify because of their similar morphologies. Our goal was to cytogenetically characterize three species belonging to Polybia (gr. occidentalis) and discuss the importance of cytogenetic data for integrative taxonomy. Polybia colonies were sampled from different regions of Brazil to perform classical and molecular cytogenetic analyses. Polybia paulista and Polybia sp. 1 showed 2n = 34 and 18S rDNA loci on two chromosomes, whereas Polybia sp. 2 showed 2n = 40 and 18S rDNA clusters on four chromosomes. The microsatellites GA(15), GAG(10), CAA(10), TTAGG(6), and TCAGG(6) showed similar distributions among the species, forming blocks in the euchromatic regions of the chromosomes, whereas CGG(10) did not yield any positive markings. In contrast, TAT(10) hybridized on the centromeric heterochromatin, showing differences in the number of marked chromosomes among the species. Therefore, it may potentially be a species‐specific cytotaxonomic marker in this group of wasps, but this feature needs further investigation. Fluorochromes evidenced that AT‐rich DAPI+ sequence distribution was coincident with heterochromatin, while the distribution of CG‐rich CMA3+ sequences was coincident with the 18S rDNA region. The present study revealed differences in diploid number, heterochromatin content, 18S rDNA sites, and microsatellite patterns between morphologically similar species, demonstrating the usefulness of cytotaxonomy in studying species complexes.

Diving deeper into the taxonomy of the Neoscopelus species complex (Myctophiformes: Neoscopelidae) with the description of Neoscopelus serranoi sp. nov.

Previous studies have highlighted possible cryptic biodiversity in the genus Neoscopelus. This hypothesis was tested using new morphological, molecular and biogeographical data on species of this genus caught in the north Atlantic between 2010 and 2022. The information obtained has been combined with available data in an integrative approach, including a review of morphological characters reported in the ichthyological literature and DNA-based species delimitation analyses. The main outcome of the present study is the description of Neoscopelus serranoi sp. nov. from the Atlantic and southwestern Indian Oceans. The new species is morphologically very similar to Neoscopelus microchir from which differs in having a shorter anal-fin base, a shorter pelvic fin, more dorsal and pectoral-fin rays, less anal-fin rays, fewer gillrakers and fewer isthmus and lateral photophores. They also differ in geographic distribution, with the new species occurring in the Atlantic Ocean and the near southwestern Indian Ocean, whereas N. microchir was originally described from Japanese waters of the Pacific Ocean. A literature review of available morphological data between geographic areas for Neoscopelus macrolepidotus and Neoscopelus microchir showed a large intraspecific overlap and no boundaries. However, molecular species delimitation based on the mitochondrial COI gene revealed the existence of cryptic diversity in both species, with eight to ten molecular operational taxonomic units (MOTU), compared to three valid species. Neoscopelus serranoi sp. nov. was considered an independent MOTU in all analyses performed, supporting the morphological identification as a new species. These results highlight that the taxonomy of Neoscopelus is far from settled and show that a greater sampling effort is needed to resolve the uncertainties and to describe unknown putative species. This also exemplifies the virtues of integrative taxonomy in delving into the systematics of deep-sea fishes.

Geraniol Inhibits Both Planktonic Cells and Biofilms of the Candida parapsilosis Species Complex: Highlight for the Improved Efficacy of Amphotericin B, Caspofungin and Fluconazole plus Geraniol.

The Candida parapsilosis species complex poses a recognized threat to the nosocomial environment. In the scenario of the global rise of resistant strains to antifungals, geraniol, a terpene isolated from different essential oils, has shown promising antimicrobial activity. We evaluated: 1- the effects of geraniol against the Candida parapsilosis species complex, in planktonic and biofilm forms; 2- the strains' susceptibility to clinical antifungals and 3- the geraniol interaction with antifungals. Eighteen isolates were subjected to in vitro susceptibility testing by the broth microdilution protocol, using geraniol, amphotericin B, caspofungin, itraconazole and fluconazole to determine the minimum inhibitory concentration (MIC) and subsequently we measured the fungicidal activity. Geraniol was tested against biofilms by the measurement of the metabolic activity and biomass. Pharmacological interactions were performed by the checkerboard method. Geraniol's MIC range was between 256 and 512 µg/ml. MIC range for clinical antifungals was ≤ 0.031-4 µg/ml. Geraniol also showed antibiofilm activity with average reductions of metabolic activity (38.33%) and biomass (30.69%), at MIC concentration. Furthermore, geraniol showed synergistic/additive effects with antifungals. Briefly, geraniol inhibits both planktonic cells and biofilms of the Candida parapsilosis species complex and besides it improves the efficacy of amphotericin B, caspofungin and fluconazole.

ScRAPdb: an integrated pan-omics database for the Saccharomyces cerevisiae reference assembly panel.

As a unicellular eukaryote, the budding yeast Saccharomyces cerevisiae strikes a unique balance between biological complexity and experimental tractability, serving as a long-standing classic model for both basic and applied studies. Recently, S. cerevisiae further emerged as a leading system for studying natural diversity of genome evolution and its associated functional implication at population scales. Having high-quality comparative and functional genomics data are critical for such efforts. Here, we exhaustively expanded the telomere-to-telomere (T2T) S. cerevisiae reference assembly panel (ScRAP) that we previously constructed for 142 strains to cover high-quality genome assemblies and annotations of 264 S. cerevisiae strains from diverse geographical and ecological niches and also 33 outgroup strains from all the other Saccharomyces species complex. We created a dedicated online database, ScRAPdb (https://www.evomicslab.org/db/ScRAPdb/), to host this expanded pangenome collection. Furthermore, ScRAPdb also integrates an array of population-scale pan-omics atlases (pantranscriptome, panproteome and panphenome) and extensive data exploration toolkits for intuitive genomics analyses. All curated data and downstream analysis results can be easily downloaded from ScRAPdb. We expect ScRAPdb to become a highly valuable platform for the yeast community and beyond, leading to a pan-omics understanding of the global genetic and phenotypic diversity.

Genome-Wide Data Uncover Cryptic Diversity With Multiple Reticulation Events in the Balkan-Anatolian Cardamine (Brassicaceae) Species Complex.

Plant species diversity may be considerably underestimated, especially in evolutionarily complex genera and in diversity hotspots that have enabled long-term species persistence and diversification, such as the Balkan Peninsula. Here, we address the topic of underexplored plant diversity and underlying evolutionary and biogeographic processes by investigating the hygrophytic mountain species complex of Cardamine acris s.l. distributed in the Balkans (three subspecies within C. acris) and northwestern Anatolia (C. anatolica). We performed a series of phylogenetic and phylogeographic analyses based on restriction-site associated DNA sequencing (RADseq) and target enrichment (Hyb-Seq) data in combination with habitat suitability modelling. We found C. anatolica as a clade nested within the Balkan C. acris, probably resulting from a founder event, and uncovered three allopatric cryptic lineages within C. acris subsp. acris, allowing us to recognise a total of six entities in this complex. We observed the deepest genetic split within C. acris subsp. acris in the western Balkans, which was at odds with taxonomy and showed no distribution gap. We inferred vicariance as the most likely process for population divergence in the Balkans, accompanied by gene flow between the recognised entities, which was consistent with the modelled habitat suitability dynamics. Furthermore, we discovered several polyploid populations in C. acris, representing both pure intra- and inter-lineage hybrid polyploids, but detected only minor traces of hybridization with related congeners. Overall, our results illustrate that diverse evolutionary processes may influence the history of mountain plant species in the Balkan Peninsula, including vicariance, reticulation, polyploidization and cryptic diversification.

New data on the poorly known Andean rodent Abrocoma uspallata (Rodentia: Abrocomidae)

Abstract The caviomorph rodent Abrocoma uspallata Braun, J.K. and Mares, M.A. (2002). Systematics of the Abrocoma cinerea species complex (Rodentia: Abrocomidae), with a description of a new species of Abrocoma. J. Mammal. 83: 1–19, doi: 10.1093/jmammal/83.1.1, stands as the most recently described species within its genus and remains one of the least studied. Known from two localities in northwestern Mendoza Province, Argentina, this elusive rodent has been the subject of four field studies conducted during 2022. The obtained evidence, including craniodental remains and fecal samples, suggest a moderate abundance of the species and a broader geographical range spanning at least 1,050 km2. Abrocoma uspallata has scattered occurrences at mid-elevations, typically around 2,000 m, across the Sierra de Uspallata and adjacent hilly systems. These findings point the species as a pre-Andean Abrocoma Waterhouse, 1837, together with Abrocoma schistacea Thomas, O. (1921). On mammals from the Province of San Juan, Western Argentina. Ann. Mag. Nat. Hist. 8th Series 9: 214–221, which occurs in the nearby province of San Juan. In addition, although treated as Vulnerable according to the last Argentinean conservation assessment, the species should be considered Least Concern.

Disentangling disjunctus: an integrated analysis of the patent leather beetle, Odontotaenius disjunctus complex (Passalidae: Coleoptera) with the description of two new species

The categorical rank of species is the fundamental taxonomic unit in characterizing biodiversity, and the accurate identification of species-level lineages is vital to all fields of biological research. This is particularly true for conservation biology, where state and federal agencies make conservation assessments based on recognized species’ distribution, ecology, and demography. Currently, there are two species of bess beetle in the conterminous United States, Odontotaenius flordianus (Schuster) and O. disjunctus (Illeger). Phylogeographic studies have proposed that O. disjunctus may represent a species complex harboring cryptic diversity. This study combines multi-locus species delimitation methods and multivariate analyses of morphological characters used to distinguish O. floridanus, to assess species diversity within the O. disjunctus complex. Delimitation methods inferred four well-supported species that diverged during the Pleistocene and whose formation was driven by historical isolation associated with shifting climatic conditions. We found a correlation between increased morphological differentiation and time since divergence. We described two new species, Odontotaenius jackmanicus sp. nov., based on morphological and molecular characters, and the cryptic species, Odontotaenius cryptodisjunctus sp. nov., diagnosed exclusively on molecular characters. We propose that the morphological similarities between O. disjunctus and O. cryptodisjunctus are due to a recent speciation combined with morphological conservatism and evolutionary stasis.

Triplex real-time PCR ZKIR-T assay for simultaneous detection of the Klebsiella pneumoniae species complex and identification of K. pneumoniae sensu stricto.

The pathogens of the Klebsiella pneumoniae species complex are widespread in food and animals and are among the main pathogens responsible for multidrug resistant infections in humans. In this study, we developed a highly sensitive detection assay that enables detection of this group of bacteria, with the simultaneous identification of the most common and clinically important species. This triplex one-reaction assay was shown to be highly sensitive and precise, enabling fast screening of varied samples for the presence of KpSC and K. pneumoniae sensu stricto.

The Vitextrifolia complex (Lamiaceae) in the Philippines.

The Vitextrifolia complex in the Philippines comprises economically important medicinal species, but its taxonomic status has become ambiguous due to numerous historical nomenclatural revisions. We assembled the complete chloroplast genomes of five species belonging to this species complex to provide additional evidence for their species delimitation. Based on a detailed analysis of specimens which combined molecular and morphological data, we propose reinstating V.elmeri Moldenke and delineating V.arvensis Gentallan, Sengun & M.B.Bartolome as a new endemic species belonging to this complex. The new species is a putative hybrid between V.bicolor Willd. and V.elmeri Moldenke. The specific epithet arvensis reflects its predominantly cultivated nature, both on a commercial scale and in home gardens, as a valued medicinal plant. We also provided a key to identify the five species belonging to the V.trifolia complex in the Philippines.

Integrating datasets from herbarium specimens and images to treat a Neotropical myrtle species complex.

Herbaria are the most important source of information for plant taxonomic work. Resources and technologies available today, such as digitised collections and herbarium DNA sequencing, can help accelerate taxonomic decisions in challenging plant groups. Here we employ an integrative methodology relying exclusively on herbarium specimens to investigate species boundaries in the Neotropical Myrcia neoobscura complex (Myrtaceae). We collected morphometric data from high-resolution images of herbarium sheets and analysed it using hierarchical clustering. We posteriorly tested the obtained morpho-groups with phylogenomics using the Angiosperms353 probe kit. We also gathered phenological and geographic information from specimen labels and built phenological histograms and ecological niche models to investigate ecological differences amongst taxa. Current circumscriptions of Myrcia arenaria, Myrcia neoglabra and Myrcia neoregeliana are confirmed in this study. Conversely, the four pieces of evidence together support Calyptranthes langsdorffii var. grandiflora, Marlierea regeliana var. parviflora and Marlierea warmingiana as separate from Myrcia marliereana, Myrcia neoriedeliana and Myrcia neoobscura, respectively, contrary to arrangements proposed by previous authors. Integrated analyses also support separation between Myrcia excoriata and two similar, undescribed taxa. Our data reveal the need for major changes in the systematics of the group, with recognition of 12 species. The successful delivery of our study aims was possible due to obtaining robust, high-quality data from museum specimens. We emphasise the importance of maintaining botanical collections physically and digitally available for taxonomic work and advocate their use to accelerate holistic taxonomic solutions of tropical species complexes. This is urgent, given the paucity of funds for fieldwork and unprecedented rates of habitat loss in the tropics.

Taxonomic re-evaluation of the Brachionus calyciflorus species complex (Rotifera) in Japanese freshwaters

AbstractRecently, the Brachionus calyciflorus species complex was divided into four nominal species: B. calyciflorus sensu stricto (s.s.) Pallas, 1766; Brachionus dorcas Gosse, 1851, Brachionus elevatus Michaloudi et al., 2018, and Brachionus fernandoi Michaloudi et al., 2018 based on the results of both morphological and molecular investigations. We applied this systematic approach to B. “calyciflorus” collected from lakes and ponds in various parts of Japan to examine spatial and temporal distributions of these species. We found that all four species indeed distributed in Japan. Among the species, B. fernandoi exhibited a somewhat different occurrence pattern and morphology. Generally, B. fernandoi appeared to occur in the winter–spring, while the other three species seemed to occur in the early summer–late autumn. A seasonal succession from B. fernandoi-dominant community to other species-dominant communities was observed in the same lakes/ponds. A statistical analysis showed that B. fernandoi-dominant species composition was also related to low temperatures. It was also found that the body of B. fernandoi was more elongated compared to those of other species. These results suggest that B. fernandoi is a distinct species in terms of morphology and phenology. Among the other three species, we observed a variation in the length of posterolateral spines. However, it was not clear if this variation is a trait that distinguish these species morphologically. In addition, some of these species co-occurred in the same lakes and ponds. The mechanism by which they coexist is a topic for future study.