Search Results (279)

This study presents a comprehensive inventory of bryophytes in Serra dos Órgãos National Park (PARNASO), aiming to evaluate species richness, floristic composition and threatened taxa. Despite the state of Rio de Janeiro being one of the most extensively sampled regions for bryophytes in Brazil, detailed surveys of its conservation units remain scarce. Data were obtained through bibliographic review, herbarium specimen analysis, and new field collections. A total of 504 species were recorded, belonging to 202 genera and 76 families. The park harbors three locally endemic species, eight endemic to Rio de Janeiro, and sixty-nine species endemic to Brazil. Additionally, eleven species were identified as threatened, comprising seven Endangered (EN), two Critically Endangered (CR), and two Vulnerable (VU) according to the IUCN guidelines. PARNASO includes four distinct ecosystems along an altitudinal gradient: sub-montane forest (up to 500 m), montane forest (500–1500 m), upper-montane forest (1500–2000 m), and high-altitude fields (above 2000 m). Montane Forest showed the highest species richness, followed by high-altitude fields, upper-montane forest, and sub-montane forest. The findings highlight PARNASO’s importance in preserving bryophyte diversity in a highly diverse yet understudied region. This work contributes valuable baseline data to support conservation strategies and future ecological studies in Atlantic Forest remnants. Full article

Phyllosphere microbial communities influence the growth and productivity of plants, particularly in epiphytic plants, which are disconnected from nutrients available in the soil. We characterized the phyllosphere of 30 individuals of the epiphytic cycad, Zamia pseudoparasitica, collected from three forest sites during the rainy and dry seasons in the Republic of Panama. We used DNA metabarcoding to describe the total bacteria community with the 16S rRNA gene and the diazotrophic community with nifH gene. Common taxa included members of the Rhizobiales, Frankiales, Pseudonocardiales, Acetobacteriales, and the diazotrophic community was dominated by Cyanobacateria. We observed similar patterns of alpha diversity across sites and seasons, and no community differences were seen within sites between the rainy and dry seasons for either the 16S rRNA or nifH genes. However, pairwise comparisons showed some statistically significant differences in community composition between sites and seasons, but these explained only a small portion of the variation. Beta diversity partitioning indicated that communities were more phylogenetically closely related than expected by chance, indicative of strong environmental or host filtering shaping these phyllosphere communities. These results highlight the influence of host-driven selection and habitat stability in shaping phyllosphere microbiota, offering new insights into microbial assembly in tropical canopy ecosystems. Full article

Membrane transporters are vital for solute movement and localisation across cellular compartments, particularly in extremophilic organisms such as Galdieriales. These red algae thrive in geothermal and metal-rich environments, where adaptive transporter systems contribute to their metabolic flexibility. While inventories of transporter genes in the species Galdieria sulphuraria have previously been compiled, their phylogenetic origins remain incompletely resolved. Here, we conduct a comparative phylogenetic analysis of three transporter families—Major Facilitator Superfamily (MFS). Amino acid–Polyamine–Organocation (APC) and the natural resistance–associated macrophage protein (Nramp)—selected from overexpressed transcripts in G. sulphuraria strain SAG 107.79. Using sequences from six Galdieriales species and orthologs from diverse taxa, we reconstructed maximum likelihood trees to assess conservation and potential horizontal gene transfer (HGT). The MFS subfamilies revealed contrasting patterns: sugar porters (SPs) exhibited polyphyly and fungal affinity, suggesting multiple HGT events, while phosphate:H⁺ symporters (PHSs) formed a coherent monophyletic group. APC sequences were exclusive in G. sulphuraria and extremophilic prokaryotes, indicating a likely prokaryotic origin. In contrast, Nramp transporters were broadly conserved across eukaryotes and prokaryotes, showing no signs of recent HGT. Together, these findings highlight the mosaic evolutionary history of membrane transporters in Galdieriales, shaped by a combination of vertical inheritance and taxon-specific gene acquisition events, and provide new insight into the genomic strategies underpinning environmental resilience in red algae. Full article

The genus Macgarvieomyces (Magnaporthales, Sordariomycetes, Ascomycota) currently includes three species, which are associated with leaf spots on plants belonging to the Cyperaceae and Juncaceae families and are known only in Europe and New Zealand. During a comprehensive survey conducted between 2020 and 2022 targeting host plants from these families across various regions of Iran, six novel species of Macgarvieomyces—M. caspica, M. cyperi, M. junci-acuti, M. juncigenus, M. salkadehensis, and M. schoeni—were uncovered. These species were identified based on detailed morphological characterizations and multi-locus phylogenetic analyses using ITS-rDNA, RPB1, ACT, and CAL gene regions. This study provides thorough descriptions and illustrations of the new taxa, including information on their morphology, ecological preferences, and geographic distribution. The phylogenetic relationships among the species are also discussed. This work significantly enhances the known diversity of Macgarvieomyces associated with Cyperaceae and Juncaceae, expands their geographic distribution, and underscores the value of integrating morphological and molecular data in fungal taxonomy; accordingly, the findings of this study lay the groundwork for future ecological and evolutionary studies of this genus. Full article

The systematics and phylogeny of the most speciose genus (Leopardus) of the felidae have historically been contentious and problematic. These issues have been compounded with the recent advancement of genetic techniques that make it possible to detect events such as incomplete lineage sorting (ILS), punctual historical ancestral introgression (PHAI), and repetitive introgression or recent hybridization (RI-RH). Each of these events have noteworthily affected the Leopardus genus. One Leopardus taxon (Leopardus tigrinus, herein called tigrina) has been especially complex from a phylogenetic point of view. In the last decade, one new species has been reported (L. guttulus) and two other new species likely exist within the tigrinas (L. emiliae and L. pardinoides). However, the most surprising find was the discovery of a new and not previously reported tigrina, the Nariño cat, from the southern Andean region of Colombia (2023). Later that same year, a new paper criticized the discovery. In response to that criticism, herein, we provide new molecular genetics results of the Nariño cat as well as new insights into the molecular phylogeny of the tigrinas inside the Leopardus genus: (1) In this new work, we analyzed the mtND5 gene of Nariño cat samples collected over four years (2001, 2007, 2017, 2023) as well as analyzed mitogenomes of Nariño cat samples collected in three different years (2001, 2017, 2023). The temporal Nariño cat samples (2001, 2007, 2017, 2023) refer to samples taken from a single specimen across different years. Based on these analyses, data from 2001 and 2007 represent the most reliable information. In contrast, samples from 2017 and 2023 may be contaminated with DNA from the Pampas cat and tigrina, respectively. (2) On the other hand, based on sequencing the mtND5 gene of 164 specimens of Leopardus, northern Andean and Central American tigrinas (37 specimens) are divided into at least six different groups (without counting the Nariño cat). Based on our analysis of sequenced mitogenomes of 102 specimens (including 34 northern Andean and Central American tigrinas) of the Leopardus genus, there are at least eight different groups of tigrinas (without counting the Nariño cat). Henceforth, there are strong datasets which support the existence of multiple lineages within the presumed “a priori” northern Andean tigrina and thus much of the genetic diversity of this wild cat has gone unnoticed. There are a series of potential taxa that have gone unnoticed due to a lack of sampling of this polyphyletic Andean feline. Full article

The rhizospheric microbial community plays a crucial role in the growth and ecological adaptation of truffles. Although extensive research has been conducted on bacterial communities in truffle habitats, the spatial variation and functional implications across different regions and soil compartments remain poorly understood in the current literature. In this study, soil bacterial communities were analyzed using 16S rRNA high-throughput sequencing across truffle-producing (Tuber sinense) and non-producing sites in Quercus aliena forests in Panzhihua, China. To capture microhabitat-level variation, soils were classified into three compartments: rhizosphere soil tightly adhering to ectomycorrhizal roots (TRS), rhizoplane soil loosely attached to roots (TRE), and bulk soil from truffle zones without visible roots (TBS), with corresponding controls (RS, RE, BS) collected from truffle-free forests. An alpha diversity analysis revealed that truffle-producing soils harbored significantly higher bacterial richness than control soils, while beta diversity indicated more clustered community composition in truffle-associated soils. A taxonomic analysis showed that T. sinense occurrence was associated with enrichment of specific bacterial taxa, including Chloroflexi, Anaeromyxobacteraceae, and Bradyrhizobium, whereas widespread taxa such as Firmicutes and Bacteroidota were more abundant in control soils. To further identify microbial indicators closely associated with truffle presence, we employed random forest modeling, which highlighted Pseudomonas, Streptomyces, and Bradyrhizobium as key genera distinguishing truffle-associated rhizospheres. These findings suggest that T. sinense may influence the composition of rhizospheric microbial communities, thereby constructing a favorable rhizospheric microenvironment. This work provides new insights into the microbial ecology of T. sinense and lays a foundation for future truffle domestication and cultivation efforts. Full article

Photosynthetic eukaryotes have shaped the Earth’s biosphere by producing oxygen and organic compounds using light energy in specialized organelles called plastids. Plastids evolved from free-living cyanobacteria ingested by heterotrophic unicellular eukaryotes. Two such independent engulfment processes, called cyanobacterial endosymbioses, have been reported. The first gave rise to primary plastids and three Archaeplastida lineages: glaucophytes, red algae, and green algae with land plants, whereas the second resulted in chromatophores in the rhizarian amoeba Paulinella. Importantly, Archaeplastidans donated their plastids to many protist groups, further spreading photosynthesis across the tree of life. To reveal complex plastid evolution, we performed comprehensive phylogenetic and molecular clock analyses using new fossil calibrations and the largest number yet of plastid-encoded proteins from 108 taxa, representing diverse photosynthetic organisms. Our results indicate that primary plastids evolved prior to 2.1–1.8 Ga, i.e., before glaucophytes diverged from other Archaeplastidans, and Paulinella chromatophores were likely before 292–266 Ma. Red and green algae were engulfed by cryptophyte and chlorarachniophyte ancestors between 1.7–1.4 Ga and 1.1–1.0 Ga, respectively; the former subsequently triggered plastid transfers to other eukaryotes. We also examined the impact of molecular clocks and calibration sets on age estimates, showing that clocks are the main source of variation. Full article

Pleosporalean fungi play significant roles as plant pathogens, saprobes, and endophytes in a wide variety of economically important plant hosts. During an investigation of saprobic fungi from Jilin and Hebei, China, five pleosporalean isolates were obtained from the dead stems of Xanthoceras sorbifolium. Morphological evidence and multi-locus sequence analyses using a combined dataset of ITS, LSU, SSU, rpb2, tef1-α, and tub2 indicate that these isolates represent two new species (Alloleptosphaeria xanthoceratis and Lophiostoma multiforme) and a new record of Lophiostoma montanae. Full morphological descriptions and illustrations are provided herein, and phylogenetic relationships of three pleosporalean taxa are also discussed. Detailed morphological descriptions and illustrations are presented, along with phylogenetic affiliations of three pleosporalean taxa. Full article

Although belowground litter decomposition critically influences lacustrine wetland soil carbon dynamics, the organ-specific microbial mechanisms driving soil organic carbon (SOC) accumulation remain unclear. Existing research has predominantly focused on aboveground litter, leaving a significant gap in the understanding of how roots and rhizomes differentially regulate carbon cycling through microbial community assembly and survival strategies. This study took Phragmites australis (a plant characteristic of lacustrine wetland) as the research object and examined how decomposing belowground litter from different organs affects microbial-mediated SOC accumulation through a one-year in situ field incubation in Jingyuetan National Forest Park, Changchun City, Jilin Province, China. Our findings reveal that root litter exhibited the highest decomposition rate, which was accelerated by intermittent flooding, reaching up to 1.86 times that of rhizome. This process enriched r-strategist microbial taxa, intensified homogeneous selection, and expanded niche width, directly promoting SOC accumulation. Rhizome litter decomposition enhanced dispersal limitation, promoted K-strategist microbial dominance, and indirectly modulated SOC through soil acidification. Mixed-litter treatments significantly enhanced SOC accumulation (up to three times higher than single-litter treatments) through synergistic nutrient release (non-additive effects < 0.04) and reinforced microbial network interactions. SOC accumulation varied significantly with the flooding regime as follows: non-flooded > intermittent flooding > permanent flooding. This study provides new insights into the microbially driven mechanisms of plant-organ-specific decomposition in the carbon cycling of wetland ecosystems. Full article

A review of the pore patterns of deep-sea benthic foraminifera is presented with a discussion of their characteristics, function and relationship with dissolved oxygen levels. Pore characteristics of deep-sea benthic foraminifera are of timely interest due to their potential for reconstructing dissolved oxygen conditions from the sedimentary record. Scanning electron micrographs of 20 epifaunal and infaunal deep-sea taxa from the Sulu Sea, Monterey Bay, California Bight and northwest Atlantic Ocean are presented to illustrate the wide range of pore patterns found in deep-sea taxa. New SEM observations of three taxa with biconvex test shapes, Oridorsalis umbonatus, Hoeglundina elegans, and Epistominella umbonifera, suggest that these taxa have an infaunal habitat for at least part of their life span. Full article

Pediatric asthma is the most common chronic childhood disease in the US and a major public health concern. It is considered to comprise multiple clinical variants or phenotypes with different etiologies and pathophysiologies. Former research has shown that airway bacteriomes vary in composition and structure across pediatric asthma phenotypes, but their functional diversity and bacterial interactions have hardly been investigated. A previous study of 163 children from Washington DC identified three statistically different asthma phenotypes, each with a unique nasopharyngeal bacterial composition and diversity. Here, I reanalyze 16S rRNA high-throughput sequences from the same cohort to characterize their bacterial metabolism and interactions. I detect 61 to 102 metabolic pathways (PICRUSt2; q ≤ 0.05) differentially expressed across the three asthma phenotypes. Most of those pathways are related to biosynthesis and degradation processes and statistically (p ≤ 0.0012) separated the three clinical groups. Co-occurrence networks also differ in connectivity across phenotypes, suggesting unique bacterial interactions in each group. Five to eight keystone taxa are detected across phenotypes. Insights from this and previous studies, hence, confirm the airway bacteriome heterogeneity across pediatric asthma, increasing our understanding of its etiology and pathophysiology, and provide new taxonomic and functional biomarkers of disease for targeted interventions and therapies. Full article

Hypocreales is one of the largest orders within the class Sordariomycetes and is renowned for its diversity of lifestyles, encompassing plant, insect, and human pathogens, as well as endophytes, parasites, and saprobes. In this study, we focused on saprobic hypocrealean fungi isolated from rice in northern Thailand. Species identification was conducted using morphological characteristics and multilocus phylogenetic analyses, including the internal transcribed spacer region (ITS), 28S large subunit nuclear ribosomal DNA (LSU), translation elongation factor 1–alpha (tef1-α), RNA polymerase II second-largest subunit (rpb2), and calmodulin (cmdA). This research confirmed the presence of 14 species of hypocrealean taxa, viz. Fusarium (9), Ochronectria (1), Sarocladium (2), Trichothecium (1), and Waltergamsia (1). Among these were two new species (Fusarium chiangraiense and F. oryzigenum), four new host records (Fusarium kotabaruense, Ochronectria thailandica, Sarocladium bactrocephalum, and Waltergamsia fusidioides), and three new geographical records (Fusarium commune, F. guilinense, and F. hainanese). Full article

The interspecific relations that have been previously observed within the Stipa dasyphylla group are intricate and require further clarification. The aim of this study was to determine whether the specimens from Serbia deserve a separate taxonomic status. Various “dasyphyllous” Stipa species (those with hairy adaxial leaves) from the Balkan Peninsula were collected and analysed using morphological methods and microscopic observations of the macro- and micro-ornamentation of their leaves and lemmas. Based on analyses of 160 individuals from 17 populations belonging to three “dasyphyllous” Stipa species (S. pontica, S. ucrainica, and S. dasyphylla) which were collected in the central and eastern Balkan Peninsula (Serbia, North Macedonia, Bulgaria, Greece) and in Central Europe (Czech Republic, Slovakia, Hungary, Romania), Stipa stevanoviciorum is described as a new species from Serbia. This taxon includes the subspecies stevanoviciorum, which grows on ultramafic substrates, and the subspecies pseudodasyphylla, which is found on carbonate bedrock. These taxa differ from the closely related S. dasyphylla primarily in the length of their upper cauline leaves and the distance from the end of the dorsal line of the hairs to the top of the anthecium. The ecological and biogeographical characteristics of the taxa and a morphological comparison with similar species are given together with the key to the species’ identification. Images of key morphological characters are included, along with information on their distribution, habitat, and conservation implications. Full article

In this study on diatoms, which are unicellular microalgae with a siliceous cell wall, images obtained by electron microscopy were used to compare three taxa from East Asia that were referred as Cyclotella hubeiana, Discostella guiyangensis and “Cyclotella fottii” in the original studies. Morphometrical and morphological analyses indicate that these three taxa are conspecific. The distinctive morphological features of this species are the following: one rimoportula located on the valve mantle within the ring of marginal fultoportulae, marginal fultoportulae situated on costae with internally two satellite pores positioned circumferentially (laterally) and externally long tubular opening, biseriate striae and branching costae. A comparison of these morphological features with those of Discostella and Cyclotella species and a re-assessment of the existing molecular data suggest that this species could be separated from both these genera. On this basis, we describe the new genus Discocyclus gen. nov. with Discocyclus hubeianus comb. nov. as the type species. Full article

The Nepetoideae are a subfamily of the Lamiaceae with 124 genera in three tribes: Elsholtzieae, Mentheae and Ocimeae. Their seeds have variable shapes, described in the literature by using adjectives derived from geometry, such as ellipsoid or elliptic, oblong, oval, ovate, ovoid, subspherical, round, spheroidal or their binary combinations. The articles describing seed shape mainly refer to single genera or even species, but a comprehensive approach covering different genera is lacking. Here we present general seed morphological measurements, curvature values and similarity to a geometric model (J-index) for seeds of the subfam. Nepetoideae. Seed morphology is described for 21 species belonging to nine genera of the three tribes and compared between genera as well as between different species in Mentha, Salvia, Thymus, Lavandula and Ocimum. The research objective was to investigate the application of the J-index and curvature analysis in the taxonomy of this subfamily. Individual genera can be defined by size and shape measurements, while species can be distinguished via the J-index and curvature. New methods are presented for studying the morphological relationships between taxa in the Nepetoideae. Full article