Phylogenetic Evidence Research Articles

Genomic comparative analysis of Ophiocordyceps unilateralis sensu lato.

Ophiocordyceps unilateralis sensu lato is a common pathogenic fungus of ants. A new species, O. fusiformispora, was described based on morphology and phylogenetic evidence from five genes (SSU, LSU, TEF1α, RPB1, and RPB2). The whole genomes of O. fusiformispora, O. contiispora, O. subtiliphialida, O. satoi, O. flabellata, O. acroasca, and O. camponoti-leonardi were sequenced and annotated and compared with whole genome sequences of other species in O. unilateralis sensu lato. The basic genome-wide characteristics of the 12 species showed that the related species had similar GC content and genome size. AntiSMASH and local BLAST analyses revealed that the number and types of putative SM BGCs, NPPS, PKS, and hybrid PKS-NRPS domains for the 12 species differed significantly among different species in the same genus. The putative BGC of five compounds, namely, NG-391, lucilactaene, higginsianin B, pyripyropene A, and pyranonigrin E were excavated. NG-391 and lucilactaene were 7-desmethyl analogs of fusarin C. Furthermore, the 12 genomes had common domains, such as KS-AT-DH-MT-ER-KR-ACP and SAT-KS-AT-PT-ACP-ACP-Te. The ML and BI trees of SAT-KS-AT-PT-ACP-ACP-Te were highly consistent with the multigene phylogenetic tree in the 12 species. This study provided a method to obtain the living culture of O. unilateralis sensu lato species and its asexual formed on the basis of living culture, which was of great value for further study of O. unilateralis sensu lato species in the future, and also laid a foundation for further analysis of secondary metabolites of O. unilateralis sensu lato.

Five new species of Pseudosperma (Inocybaceae, Agaricales) from Benin and Turkey based on morphological characteristics and phylogenetic evidence

Species of Pseudosperma (Inocybaceae) are widely distributed from temperate to tropical regions. In this study, we describe and illustrate five new species of Pseudosperma: P. beninense, P. cremeo-ochraceum, P. squarrosofulvum, P. stramineum, and P. tiliae, based on comprehensive analyses of morphological and molecular data derived from specimens collected in Benin (West Africa) and Turkey (Western Eurasia). These new species have been found in forests with Isoberlinia spp. and other ectomycorrhizal tree species in Benin and in association with Tilia platyphyllos in Turkey. The phylogenetic relationships of the new species were inferred through analyses of nuclear rDNA sequences, encompassing the internal transcribed spacer (ITS), 28S rDNA, and RNA polymerase II second largest subunit (RPB2) region. Phylogenetic analyses revealed that P. beninense, P. cremeo-ochraceum, P. squarrosofulvum, and P. stramineum from Benin cluster with species from Australia, China, and India within a clade formed exclusively by species known from the palaeotropics and Australia, whereas P. tiliae from Turkey clustered with P. mediterraneum from Italy. Detailed descriptions are provided, supplemented by illustrations and line drawings of key micromorphological features. In addition, a comparative analysis with morphologically similar and phylogenetically closely related species is presented and discussed in detail.

Molecular phylogeny and morphology of Sporodiniella sinensis sp. nov. (Syzygitaceae, Mucorales), an invertebrate-associated species from Yunnan, China.

During investigations of invertebrate-associated fungi in Yunnan Province of China, a new species, Sporodiniella sinensis sp. nov., was collected. Morphologically, S. sinensis is similar to Sporodiniella umbellata; however, it is distinguished from S. umbellata by its greater number of sporangiophore branches, longer sporangiophores, larger sporangiospores, and columellae. The novel species exhibits similarities of 91.62 % for internal transcribed spacer (ITS), 98.66-99.10 % for ribosomal small subunit (nrSSU), and 96.36-98.22 % for ribosomal large subunit (nrLSU) sequences, respectively, compared to S. umbellata. Furthermore, phylogenetic analyses based on combined sequences of ITS, nrLSU and nrSSU show that it forms a separate clade in Sporodiniella, and clusters closely with S. umbellata with high statistical support. The phylogenetic and morphological evidence support S. sinensis as a distinct species. Here, it is formally described and illustrated, and compared with other relatives.

Molecular phylogenetics of the Umbelopsis genus-identification of new species and evaluation of their oil application value.

The aim of this study was to reconstruct the evolutionary framework of the genus Umbelopsis by using modern taxonomic strategies and evaluating the quality of oil and prospective uses of three distinct species. Three species of Umbelopsis were identified based on morphological characteristics and phylogenetic evidence obtained from three genes (ITS, LSU, and ACT). A new species of Umbelopsis was described and illustrated, and subsequently named U. ophiocordycipiticola. The characteristics of U. ophiocordycipiticola exhibited sporangia with a diameter ranging from 8 to 17µm. and sporangiospores that were oval to ellipsoidal in shape, irregularly angular, with dimensions of ∼1.9-2.9×1.7-3.0µm. Gas chromatography and mass spectrometry (GC-MS) were used to examine the composition of fatty acids. Notably, U. ophiocordycipiticola showed a significantly higher oil content of 50.89% in dry cell weight (DCW) compared to U. vinacea and U. ramanniana. The mean proportion of polyunsaturated fatty acids (PUFAs) in U. ophiocordycipiticola was 32.38%, and the maximum levels of γ-linolenic acid (GLA), arachidonic acid (ARA), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) in U. ophiocordycipiticola were found to be 14.51, 0.24, 0.54, and 0.53%, respectively. The biodiesel quality from all three species complied with applicable standards set by the American Association for Testing and Materials (ASTM 6751) and the Brazilian National Petroleum Agency (ANP 255). The establishment of a novel species, U. ophiocordycipiticola, was strongly supported by morphological and molecular evidence. Umbelopsis ophiocordycipiticola exhibited a high-value PUFA content. Additionally, three Umbelopsis species demonstrated good quality for biodiesel production.

Metarhizium dianzhongense sp. nov. and New Record of M. bibionidarum (Clavicipitaceae, Hyocreales) Attacking Insects from China

The genus Metarhizium is one of the most significant entomopathogenic fungi with diverse morphological characteristics and host species. Species of Metarhizium have been widely used for pest control as an environmentally safe alternative to chemical pesticides. This study reports a new species of Metarhizium and a new record of M. bibionidarum from China. The taxonomic positions of the two species within Metarhizium were assessed by morphological and multi-gene phylogenetic data. This assessment confirmed that the new species M. dianzhongense on white grubs (Coleoptera) is a sister to M. ellipsoideum on adult leafhoppers (Hemiptera) and represents a distinctive fungus according to the morphological and phylogenetic evidence. The two species, M. dianzhongense and M. bibionidarum, were described and illustrated. Pathogenicity tests by M. bibionidarum and M. dianzhongense were performed on early instar larvae of the significant agricultural pest Spodoptera frugipera (Lepidoptera). The results demonstrated that both M. bibionidarum and M. dianzhongense exhibit significant insecticidal activity against larvae of S. frugipera, providing new fungal resources for the development of an eco-friendly biocontrol agent against this pest.

Re-establishment of Aechmea laxiflora (Bromeliaceae, Bromelioideae) based on morphological and phylogenetic evidence, with notes on its geographical distribution

Background: Previous phylogenetic analyses suggested that Aechmea bracteata is not a monophyletic species, being each variety an individual lineage within the Aechmea bracteata complex.
 Hypothesis: A phylogenetic analysis based on molecular data and a morphological analysis will provide evidence to support the taxonomic recognition of A. bracteata var. pacifica as a distinct species.
 Studies species: A. bracteata var. bracteata, A. bracteata var. pacifica and related species.
 Study site and dates: Mexico to Northern South America; 17 populations from Southeastern and Western Mexico. Analyses were performed between 2021 and 2023.
 Methods: A linear morphometric analysis was conducted with 85 herbarium specimens testing 28 quantitative and three qualitative variables. Potential diagnostic traits were reviewed in living specimens. A phylogenetic analysis was performed with two nDNA markers (ETS and g3pdh) and one cpDNA marker (trnL-F). A total of 373 records were projected into biogeographical provinces of the Neotropics.
 Results: The morphometric analysis allowed to separate each variety into a group, also, nine of the evaluated traits resulted statistically significant through a univariate analysis. Five additional diagnostic traits from the inflorescence and leaves were recognized. According to nDNA both taxa present reciprocal monophyly, however, cpDNA groups A. bracteata var. pacifica with Central American species, showcasing a potential hybrid origin. Geographically, the Sierra Madre del Sur acts as a barrier between both taxa.
 Conclusions: Due to the gathered evidence is possible to recognize A. bracteata var. pacifica as an endemic species to Mexico, reestablishing the basionym A. laxiflora.

Catalogue of fungi in China 1. New taxa of plant-inhabiting fungi

ABSTRACT China has a huge area of diverse landscapes and is believed to conceive incredibly high fungal diversity. To systematically and promptly report Chinese fungal species, we initiate the series of Catalogue of fungi in China here. In the first paper of this series, we focus on plant-inhabiting fungi. A total of 33 new taxa are described all over China. These taxa include two new genera, viz. Cremeoefibula and Nothopucciniastrum, 18 new species, viz. Annulohypoxylon lancangensis, Ascotaiwania coffeae, Clitocella neofallax, Coleopuccinia yunnanensis, Cremeoefibula hengduanensis, Crepidotus furcaticystidiosus, C. tomentellus, Diachea macroverrucosa, Helicogloea hangzhouensis, Hyalopsora caprearum, Nemania polymorpha, Phanerochaetella austrosinensis, Physalacria tianzhongshanensis, Setophaeosphaeria panlongensis, Subulicystidium boreale, Trechispora subaraneosa, Vikalpa dujuanhuensis, and Xylaria pteridicola, and 13 new combinations, viz. Nothopucciniastrum actinidiae, N. boehmeriae, N. coriariae, N. corni, N. coryli, N. fagi, N. kusanoi, N. hikosanense, N. hydrangeae-petiolaris, N. miyabeanum, N. styracinum, N. tiliae, and N. yoshinagae. The morphological characteristics and phylogenetic evidence are used to support the establishment of these new taxa and the accuracy of their taxonomic placements. We hope that the series of Catalogue of fungi in China will contribute to Chinese fungal diversity and promote the significance of recording new fungal taxa from China.

New Data on Boletaceae (Agaricomycetes, Basidiomycota) from Central Vietnam with Description of Two New Species and Creation of a New Combination Based on Morphological and Phylogenetic Evidence.

Two new species of Boletaceae (Hortiboletus rubroreticulatus and Tylopilus aurantiovulpinus) discovered during an investigation of the mycobiota of Central Vietnam (Kon Chu Rang Nature Reserve; Ta Dung National Park; Bidoup-Nui Ba National Park; Kon Ka Kinh National Park) are described on the basis of molecular and morphological data. Illustrated descriptions of their macro- and microscopic features and discussion on similar taxa are given. Additionally, eight species which were recorded for the first time in Vietnam are listed and illustrated here. A new combination Kgaria virescens was made for one of these species. These results were confirmed by the phylogenetic analysis based on nrITS1-5.8S-ITS2, nrLSU, and tef1α regions.

How Does Selfing Affect the Pace and Process of Speciation?

Surprisingly little attention has been given to the impact of selfing on speciation, even though selfing reduces gene flow between populations and affects other key population genetics parameters. Here we review recent theoretical work and compile empirical data from crossing experiments and genomic and phylogenetic studies to assess the effect of mating systems on the speciation process. In accordance with theoretical predictions, we find that accumulation of hybrid incompatibilities seems to be accelerated in selfers, but there is so far limited empirical support for a predicted bias toward underdominant loci. Phylogenetic evidence is scarce and contradictory, including studies suggesting that selfing either promotes or hampers speciation rate. Further studies are therefore required, which in addition to measures of reproductive barrier strength and selfing rate should routinely include estimates of demographic history and genetic divergence as a proxy for divergence time.

Phylloporia vietnamensis sp. nov. (Hymenochaetales, Basidiomycota) from Vietnam

Phylloporia, belonging to Hymenochaetaceae, Hymenochaetales, is a cosmopolitan genus; some species are plant pathogens and possess medicinal properties. The species diversity of Phylloporia has been extensively explored; however, there is still no known record available from certain regions. Phylloporia vietnamensis is described here, as a new species from Vietnam based on morphological and phylogenetic evidence. This is the first report of the genus Phylloporia in Vietnam. Phylloporia vietnamensis is characterized by annual, terrestrial, eccentrically stipitate basidiomes with small pores (9–11 per mm) and thick stipe (up to 1.5 cm in diam), a dimitic hyphal system in the upper tomentum, and the presence of cystidioles. Phylogenetically, P. vietnamensis occupied an independent lineage within the Phylloporia clade. This work will hopefully attract more attention to taxonomic works on Phylloporia in Vietnam.

Triplostegia alpina (Caprifoliaceae): a new species from Southwest China

The species delimitation of Triplostegia has been controversy and traditionally includes two species: T. glandulifera and T. grandiflora. These two taxa differs in some morphological characters on leaves, size of corollas, and achene involucel apex. A recent study proposed to merge these two species into a single taxon, T. glandulifera, while the phylogenetic and morphological evidence suggests that this genus consists of three distinct species, including an undescribed species that is distributed in the Hengduan Mountains Region and east Himalaya. Following the phylogenetic and morphological thesis, the authors describe and illustrate this new species: Triplostegia alpina. This taxon is characterized by a brown main taproot with fine roots and one to three more slender white glabrous lateral taproots, petiolate and serrated leaves, corollas 1.1–2.2 mm, achene involucel apex in purple and slightly hooked, which are distinctive from its two congeners. The study highlight the diagnostic role of taproot, leaf, corolla, and achene involucel in delimiting Triplostegia species.

Incomplete lineage sorting and gene flow within Allium (Amayllidaceae)

The phylogeny and systematics of the genus Allium have been studied with a variety of diverse data types, including an increasing amount of molecular data. However, strong phylogenetic discordance and high levels of uncertainty have prevented the identification of a consistent phylogeny. The difficulty in establishing phylogenetic consensus and evidence for genealogical discordance make Allium a compelling test case to assess the relative contribution of incomplete lineage sorting (ILS), gene flow and gene tree estimation error on phylogenetic reconstruction. In this study, we obtained 75 transcriptomes of 38 Allium species across 10 subgenera. Whole plastid genome, single copy genes and consensus CDS were generated to estimate phylogenetic trees both using coalescence and concatenation methods. Multiple approaches including coalescence simulation, quartet sampling, reticulate network inference, sequence simulation, theta of ILS and reticulation index were carried out across the CDS gene trees to investigate the degrees of ILS, gene flow and gene tree estimation error. Afterward, a regression analysis was used to test the relative contributions of each of these forms of uncertainty to the final phylogeny. Despite extensive topological discordance among gene trees, we found a fully supported species tree that agrees with the most of well-accepted relationships and establishes monophyly of the genus Allium. We presented clear evidence for substantial ILS across the phylogeny of Allium. Further, we identified two ancient hybridization events for the formation of the second evolutionary line and subg. Butomissa as well as several introgression events between recently diverged species. Our regression analysis revealed that gene tree inference error and gene flow were the two most dominant factors explaining for the overall gene tree variation, with the difficulty in disentangling the effects of ILS and gene tree estimation error due to a positive correlation between them. Based on our efforts to mitigate the methodological errors in reconstructing trees, we believed ILS and gene flow are two principal reasons for the oft-reported phylogenetic heterogeneity of Allium. This study presents a strongly-supported and well-resolved phylogenetic backbone for the sampled Allium species, and exemplifies how to untangle heterogeneity in phylogenetic signal and reconstruct the true evolutionary history of the target taxa.

Ad-derived bone marrow transplant induces proinflammatory immune peripheral mechanisms accompanied by decreased neuroplasticity and reduced gut microbiome diversity affecting AD-like phenotype in the absence of Aβ neuropathology

Immune system dysfunction is increasingly recognized as a significant feature that contributes to Alzheimer’s disease (AD) pathogenesis, reflected by alterations in central and peripheral responses leading to detrimental mechanisms that can contribute to the worsening of the disease. The damaging alterations in the peripheral immune system may disrupt the peripheral-central immune crosstalk, implicating the gut microbiota in this complex interaction. The central hypothesis posits that the immune signature inherently harbored in bone marrow (BM) cells can be transferred through allogeneic transplantation, influencing the recipient’s immune system and modulating peripheral, gut, and brain immune responses.Employing a genetically modified mouse model to develop AD-type pathology we found that recipient wild-type (WT) mice engrafted with AD-derived BM, recapitulated the peripheral immune inflammatory donor phenotype, associated with a significant acceleration of cognitive deterioration in the absence of any overt change in AD-type amyloid neuropathology. Moreover, transcriptomic and phylogenetic 16S microbiome analysis evidence on these animals revealed a significantly impaired expression of genes associated with synaptic plasticity and neurotransmission in the brain and reduced bacteria diversity, respectively, compared to mice engrafted with WT BM.This investigation sheds light on the pivotal role of the peripheral immune system in the brain-gut-periphery axis and its profound potential to shape the trajectory of AD.In summary, this study advances our understanding of the complex interplay among the peripheral immune system, brain functionality, and the gut microbiome, which collectively influence AD onset and progression.

Cranial and postcranial anatomy of a juvenile baurusuchid (Notosuchia, Crocodylomorpha) and the taxonomical implications of ontogeny.

Baurusuchidae comprises a clade of top-tier terrestrial predators and are among the most abundant crocodyliforms found in the Adamantina Formation, Bauru Basin, Brazil (Campanian-Maastrichtian). Here, we provide a detailed description of the cranial and postcranial osteology and myology of the most complete juvenile baurusuchid found to date. Although the preservation of juvenile individuals is somewhat rare, previously reported occurrences of baurusuchid egg clutches, a yearling individual, and larger, but skeletally immature specimens, comprise a unique opportunity to track anatomical changes throughout their ontogenetic series. Its cranial anatomy was resolved with the aid of a three-dimensional model generated by the acquisition of computed tomography data, and its inferred adductor mandibular musculature was compared to that of mature specimens in order to assess possible ontogenetic shifts. A subsequent phylogenetic analysis included the scoring of Gondwanasuchus scabrosus, the smallest baurusuchid species known to date, to evaluate its phylogenetic relations relative to a known juvenile. We find considerable differences between juveniles and adults concerning skull ornamentation and muscle development, which might indicate ontogenetic niche partitioning, and also anatomical and phylogenetic evidence that G. scabrosus corresponds to a young semaphoront lacking mature cranial features.

Two novel species of arctic-alpine lichen-forming fungi (Ascomycota, Megasporaceae) from the Deosai Plains, Pakistan.

Members of the lichen-forming fungal genus Oxneriaria are known to occur in cold polar and high altitudinal environments. Two new species, Oxneriariacrittendenii and O.deosaiensis, are now described from the high altitude Deosai Plains, Pakistan, based on phenotypic, multigene phylogenetic and chemical evidence. Phenotypically, O.crittendenii is characterised by orbicular light-brown thalli 1.5-5 cm across, spot tests (K, C, KC) negative, apothecia pruinose, hymenium initially blue then dark orange in response to Lugol's solution. Oxneriariadeosaiensis is characterised by irregular areolate grey thalli 1.5-2 cm across, K test (light brown), KC test (dark brown), apothecia epruinose, hymenium initially blue then dark blue in response to Lugol's solution. Both species share the same characters of thalli with black margins and polarilocular ascospores. The closest previously reported species, O.pruinosa, differs from O.crittendenii and O.deosaiensis in having non-lobate margins, thin thalline exciple (45-80 μm thick), short asci (55-80 × 25-42 μm) and K positive (yellow) and KC negative tests and divergent DNA sequence in the ITS, LSU and mtSSU regions. The newly-described Oxneriaria species add to growing evidence of the Deosai Plains as a region of important arctic-alpine biodiversity.

Phylogenetic evidence reshapes the taxonomy of Cacao and its allies (Theobroma and Herrania; Malvaceae, Byttnerioideae)

Theobroma (Malvaceae, Byttnerioideae), the cacao genus, has a taxonomic history spanning over two centuries. Currently, it comprises 23 species of trees from lowland forests from the Tropical Americas. Herrania, a closely related genus described later, includes 17 additional species commonly referred to as “wild cacaos.” Phylogenetic relationships and morphological circumscriptions between Theobroma and Herrania have been the subject of debate. While Herrania has traditionally been treated as a separate genus based on evident morphological differences in leaf and petal features, it shares similarities with Theobroma in terms of habit, inflorescence, and fruit types. Recent phylogenetic evidence, incorporating a broader taxonomic sampling and a total-evidence analysis, suggested that Theobroma is paraphyletic, with Herrania nested within it. This finding supports the restoration of a classical circumscription of Theobroma wherein Herrania is considered a section of the former genus. Here, we provide a detailed account of the taxonomic history at infrageneric levels and propose one new subsection, two names at new ranks (to better allocate the diversity within T. sect. Herrania), and nine new combinations encompassing this expanded circumscription of Theobroma. In our study, we delimit Theobroma with forty species divided into six sections: T. sect. Glossopetalum (14 spp.), T. sect. Herrania (17 spp.), T. sect. Oreanthes (5 spp.), T. sect. Rhytidocarpus (1 sp.), T. sect. Telmatocarpus (2 spp.), and T. sect. Theobroma (1 sp.). Furthermore, we recognize three subsections within T. sect. Herrania. Alongside these newly proposed changes, we present a section-level identification key and provide diagnostic characters for each taxon.

Evolutionary origins of Fibonacci phyllotaxis in land plants

Fibonacci phyllotaxis is commonly seen in all major groups of land plants. While a precise correlation is found between the internal pattern of the primary vascular system and the external pattern of appendages on the stem surface, it remains a big question how this regularity of Fibonacci phyllotaxis came into being in the course of evolution. Here I address this problem with a model describing phylogenetic and ontogenetic changes in vascular phyllotaxis based on two hypotheses. The first is that the Fibonacci pattern of vascular connection is uniquely determined by the primary arrangement of incipient primordia, the sources of the primary signal system in vascular tissue differentiation. The second is that the surface-area-to-volume ratio of primary vascular tissues serves as a measure of fitness in evolution. The model explains the empirical rule on the manner in which vascular connection is reconfigured during ontogeny, especially during juvenile development. Fossil and phylogenetic evidence suggests that Fibonacci phyllotaxis appeared shortly after the innovation of indefinite lateral organ initiation in a regular sequence.

Three New Periconia Species Isolated from Wurfbainia villosa in Guangdong, China: A Discussion on the Doubtful Taxa Clustering in this Genus

During a survey of fungi on Wurfbainia villosa in Guangdong Province, China, three novel species, Periconia endophytica, P. yangjiangensis, and P. wurfbainiae, belonging to Periconiaceae in Pleosporales, Dothideomycetes are proposed based on morphological and phylogenetic evidence. Periconia endophytica was isolated from the healthy leaves of W. villosa, while P. yangjiangensis and P. wurfbainiae were obtained from the dead stems of the same host. Notably, holomorphs were observed in P. wurfbainiae. The morphological characteristics of the novel taxa are compared with closely related species within Periconia. Illustrations, morphological descriptions, and phylogenetic analyses are provided for the novel taxa. Multilocus phylogeny of the combined internal transcribed spacer (ITS), large subunit nuclear rDNA (LSU), small subunit nuclear ribosomal rDNA (SSU), and partial translation elongation factor 1–α (tef1-α) regions supported the establishment of three new species. Furthermore, the taxa clustering in Periconia, Flavomyces fulophazii, and Sporidesmium tengii, are discussed for further investigation of their taxonomic placements.

Increased α-ketoglutarate links the C3-C4 intermediate state to C4 photosynthesis in the genus Flaveria.

As a complex trait, C4 photosynthesis has multiple independent origins in evolution. Phylogenetic evidence and theoretical analysis suggest that C2 photosynthesis, which is driven by glycine decarboxylation in the bundle sheath cell, may function as a bridge from C3 to C4 photosynthesis. However, the exact molecular mechanism underlying the transition between C2 photosynthesis to C4 photosynthesis remains elusive. Here, we provide evidence suggesting a role of higher α-ketoglutarate (AKG) concentration during this transition. Metabolomic data of 12 Flaveria species, including multiple photosynthetic types, show that AKG concentration initially increased in the C3-C4 intermediate with a further increase in C4 species. Petiole feeding of AKG increases the concentrations of C4-related metabolites in C3-C4 and C4 species but not the activity of C4-related enzymes. Sequence analysis shows that glutamate synthase (Fd-GOGAT), which catalyzes the generation of glutamate using AKG, was under strong positive selection during the evolution of C4 photosynthesis. Simulations with a constraint-based model for C3-C4 intermediate further show that decreasing the activity of Fd-GOGAT facilitated the transition from a C2-dominant to a C4-dominant CO2 concentrating mechanism. All these results provide insight into the mechanistic switch from C3-C4 intermediate to C4 photosynthesis.

Armillaria korhonenii, the sixteenth biological species of Armillaria from China

Armillaria korhonenii, designated as Chinese biological species Q (CBSQ) here, is described as a new species based on phylogenetic and morphological evidence as well as the results of mating tests. This species is the sixteenth biological species of Armillaria reported from China following the discovery of 15 previously known biological species. Phylogenetically, A. korhonenii is the earliest divergent lineage of the genus Armillaria as inferred from the nucleotide sequences of the Elongation Factor 1-Alpha (EF1a). Morphologically, it is characterized by its ellipsoid to elongate basidiospores, yellowish orange to honey yellow pileus with fibrillose squamules. Mating tests indicated that A. korhonenii is a tetrapolar heterogeneous species and is inter-sterile with all the tested species except partial compatibility with CBSH.