Five new Camillea (Xylariales) species described from French Guiana.

BACKGROUND: The genus Camillea was created in 1849 from collections made in French Guiana with eight species included. Numerous species assigned to Camillea were subsequently discovered, especially in the forests of the Amazon basin, but new discoveries have not been reported from French Guiana since 1849. Recent fieldwork in French Guiana has begun to fill this gap by identifying five new species, most of which were collected in the vicinity of Saül village. RESULTS: Based on macro- and micromorphological study of their stromata, including SEM images of ascospore wall ornamentation, five new species were recognized, including C. cribellum, C. heterostomoides, C. nitida, C. rogersii and C. saulensis. Cultures could be obtained for C. heterostomoides and C. rogersii, and ITS and LSU sequences were obtained for all of the five new species. Camillea heterostoma and its variety microspora were shown to be conspecific. Provisional molecular phylogenetic analyses support the possible reinstatement of Hypoxylon melanaspis, currently regarded as merely an applanate form of C. leprieurii. CONCLUSION: The current study is based on a relatively limited fieldwork in its duration and sampling area but was able to substantially increase the number of Camillea species known from French Guiana. This augurs an exceptional and still unknown diversity of the genus in this area and by extension in the adjacent neotropical forests.

Xylaria furcata reconsidered and nine resembling species.

BACKGROUND: Xylaria collections from termite nests with dichotomously branched stromata have been identified as X. furcata. However, Léveillé's original material is no longer available, and the modern interpretation of X. furcata is based on a 1908 collection made by von Höhnel from termite nests at Buitenzorg Botanical Garden in Java. A packet of this von Höhnel material at FH was designated as the neotype by Rogers et al. in 2005. RESULTS: We reexamined the neotype from FH and its duplicates from various herbaria and found that three different species were mixed in these specimens. Despite that all of them have dichotomously branched stromata and tiny ascospores, only one fits the 2005 neotypification of X. furcata, where exposed perithecial mounds on the stromatal surface were unambiguously indicated. This portion of material is redesignated as the neotype, while the other two species with immersed perithecia are described as new: X. hoehnelii and X. robustifurcata. The ITS sequence obtained from the neotype helped us designate a specimen with cultures obtained from it as the epitype. From specimens identifiable as X. furcata, we describe four new species: X. brevifurcata, X. furcatula, X. insignifurcata, and X. tenellifurcata. Additionally, we recognize X. furcata var. hirsuta at the species level as X. hirsuta and consider X. scoparia a distinct species rather than a synonym of X. furcata. Molecular phylogenetic analyses based on three protein-coding loci showed that X. furcata and resembling species were grouped into two clusters: the X. furcata cluster with half-exposed to fully exposed perithecial mounds and the X. hoehnelii cluster with largely immersed perithecial mounds. CONCLUSION: Ten species are recognized for X. furcata and resembling species, all of which could have been identified as X. furcata in the past. Its diversity has been overlooked primarily due to the small and similar stromata. Several additional species have been confirmed to be related to X. furcata by DNA sequences but are yet to be described due to the lack of mature stromata. While the species diversity of macrotermitine termites is equally high in Africa as in Asia, all of the species are primarily found in Asia, with X. hirsuta as the only exception. This suggests that there may be many more undiscovered species for this fungal group.

Xylaria species associated with fallen leaves and petioles.

BACKGROUND: Xylaria species growing on fallen leaves and petioles have not been treated systematically. One source of confusion in this group of Xylaria species has stemmed from X. filiformis, which is an ancient name published in 1805 as Sphaeria filiformis and has commonly labeled on specimen packets that contain leaf- and petiole-inhabiting Xylaria species. Here we clarified the identity of X. filiformis and distinguish it from the species that are easily confused with it, notably X. simplicissima, to which most specimens labeled as X. filiformis are referred. Our research also led us to encounter many other leaf- and petiole-inhabiting Xylaria species, prompting a comprehensive study of this group of fungi. RESULTS: Forty-five foliicolous and caulicolous species of Xylaria were studied, including nine newly described species-X. allima, X. appendiculatoides, X. hispidipes, X. minuscula, X. neblinensis, X. spiculaticlavata, X. vermiformis, X. vittatipiliformis, and X. vittiformis; three unnamed species-X. sp. AR1741, X. sp. GS7461A, and X. sp. GS7461B; X. simplicissima, a name newly combined with Xylaria from Rhizomorpha simplicissima; and X. noduliformis and X. imminuta, which are two new replacement names, respectively, for X. maitlandii var. nuda and X. hypsipoda var. microspora. The 45 taxa can be classified into three groups by stromatal shape and conspicuousness of perithecial mounds on the stromatal surface: (i) the X. filiformis group contains 10 species, (ii) the X. phyllocharis group contains 19 species, and (iii) the X. heloidea group contains 16 species. One of the newly described or unnamed species belongs to the X. filiformis group-X. vermiformis; nine of them belong to the X. phyllocharis group-X. allima, X. appendiculatoides, Xylaria minuscula, X. neblinensis, X. sp. AR1741, X. sp. GS7461B, X. spiculaticlavata, X. vittatipiliformis, and X. vittiformis; and three of them belong to the X. heloidea group-X. hispidipes, X. imminuta, and X. sp. GS7461A. CONCLUSION: The 45 species of Xylaria associated with fallen leaves and petioles can be identified by using the dichotomous identification key that we provided herein. It is important to note that most of the studied species are represented by only one or several specimens and many have not been recollected and cultured.

Wulingshen, the massive Xylaria sclerotia used as traditional Chinese medicine, is produced by multiple species.

Wulingshen, massive Xylaria sclerotia, was originally reported from Chengdu Plain in western Sichuan of China for medicinal application. Xylaria nigripes is commonly connected to these massive sclerotia produced within abandoned underground macrotermitine termite nests. We sequenced 54 Wulingshen samples procured from traditional Chinese medicine markets in Chengdu Plain and connected them to six different Xylaria species: X. nigripes, X. subescharoidea, two species newly described herein-X. neonigripes and X. rogersionigripes, and two species that are known only as sclerotia thus far. Only teleomorphs of X. subescharoidea and X. rogersionigripes have been collected in Chengdu Plain thus far. In Taiwan, teleomorphs of four of the six species, except for the two only known in sclerotial form, have been collected, and their cultures were obtained; we thus designate the holotypes of X. neonigripes and X. rogersionigripes on the basis of Taiwan specimens. During the collecting activities carried out in Chengdu Plain, a Xylaria species, which is newly described as X. mianyangensis herein, was also collected from termite nests but lacks a known connection to Wulingshen.

Ecological generalism drives hyperdiversity of secondary metabolite gene clusters in xylarialean endophytes.

Although secondary metabolites are typically associated with competitive or pathogenic interactions, the high bioactivity of endophytic fungi in the Xylariales, coupled with their abundance and broad host ranges spanning all lineages of land plants and lichens, suggests that enhanced secondary metabolism might facilitate symbioses with phylogenetically diverse hosts. Here, we examined secondary metabolite gene clusters (SMGCs) across 96 Xylariales genomes in two clades (Xylariaceae s.l. and Hypoxylaceae), including 88 newly sequenced genomes of endophytes and closely related saprotrophs and pathogens. We paired genomic data with extensive metadata on endophyte hosts and substrates, enabling us to examine genomic factors related to the breadth of symbiotic interactions and ecological roles. All genomes contain hyperabundant SMGCs; however, Xylariaceae have increased numbers of gene duplications, horizontal gene transfers (HGTs) and SMGCs. Enhanced metabolic diversity of endophytes is associated with a greater diversity of hosts and increased capacity for lignocellulose decomposition. Our results suggest that, as host and substrate generalists, Xylariaceae endophytes experience greater selection to diversify SMGCs compared with more ecologically specialised Hypoxylaceae species. Overall, our results provide new evidence that SMGCs may facilitate symbiosis with phylogenetically diverse hosts, highlighting the importance of microbial symbioses to drive fungal metabolic diversity.

Xylaria insolita and X. subescharoidea: two newly described species collected from a termite nesting site in Hua-lien, Taiwan.

BACKGROUND: A number of Xylaria species are exclusively associated with nests of macrotermitine termites. A nesting site of Odontotermes formosanus in eastern Taiwan, which is the only macrotermitine termite known on the island, had been inundated during the raining season of 2010, and hundreds of Xylaria stromata emerged from it thereafter. A thorough examination of these stromata showed that they represent a mixture of different species. RESULTS: Five Xylaria species were identified from the stromata collected from the nesting site, including two undescribed species, which are newly described as X. insolita and X. subescharoidea herein, and three known species X. brunneovinosa, X. escharoidea, and X. furcata. CONCLUSION: Totally, there are 28 Xylaria species growing on termite nests or ground in the world. Although O. formosanus is the only macrotermitine species known in Taiwan, the Xylaria diversity associated with its nests is fairly high; the species number has reached 12 with X. furcata, X. insolita, and X. subescharoidea added to the Taiwan mycobiota.

Xylaria species associated with fallen fruits and seeds.

Twenty-five fructicolous and seminicolous species of Xylaria are classified into three groups by stromatal morphology: (i) the X. ianthinovelutina group; (ii) the X. carpophila group; and (iii) the X. heloidea group. Xylaria reevesiae, X. rossmanae, and X. vivantii are described as new species. Xylaria reevesiae belongs to the X. carpophila group, resembling X. euphorbiicola but differing from it mainly by having conspicuous perithecial mounds and growing on fallen fruits of a different host plant. Xylaria rossmanae and X. vivantii belong to the X. ianthinovelutina group. Xylaria rossmanae differs from the species of the group mainly by larger, paler, fusoid-inequilateral ascospores, and X. vivantii differs by larger ascospores with a slightly oblique germ slit. A dichotomous key is provided for identifying the 25 species. Doubtful names are also listed and annotated.

Medicinal components in Termitomyces mushrooms.

Termitomyces is a genus of edible mushrooms commonly consumed in Africa and Asia among the mushrooms collected from the wild. Termitomyces mushrooms grow as symbionts in the termite nests, where they produce various enzymes to help termites digest lignocellulosic substrates. Many species of Termitomyces are used by different ethnic groups with ethnomedicinal knowledge. Bioactive components that Termitomyces mushrooms contain have potential uses as antioxidants, immunomodulators, antitumors, and antimicrobials. Termitomyces also has a potential for treating neurodegenerative disorders. Here, we review the bioactive compounds from Termitomyces species that have been isolated and assayed in vitro and/or in vivo for their medicinal properties.

A termite symbiotic mushroom maximizing sexual activity at growing tips of vegetative hyphae.

BACKGROUND: Termitomyces mushrooms are mutualistically associated with fungus-growing termites, which are widely considered to cultivate a monogenotypic Termitomyces symbiont within a colony. Termitomyces cultures isolated directly from termite colonies are heterokaryotic, likely through mating between compatible homokaryons. RESULTS: After pairing homokaryons carrying different haplotypes at marker gene loci MIP and RCB from a Termitomyces fruiting body associated with Odontotermes formosanus, we observed nuclear fusion and division, which greatly resembled meiosis, during each hyphal cell division and conidial formation in the resulting heterokaryons. Surprisingly, nuclei in homokaryons also behaved similarly. To confirm if meiotic-like recombination occurred within mycelia, we constructed whole-genome sequencing libraries from mycelia of two homokaryons and a heterokaryon resulting from mating of the two homokaryons. Obtained reads were aligned to the reference genome of Termitomyces sp. J132 for haplotype reconstruction. After removal of the recombinant haplotypes shared between the heterokaryon and either homokaryons, we inferred that 5.04% of the haplotypes from the heterokaryon were the recombinants resulting from homologous recombination distributed genome-wide. With RNA transcripts of four meiosis-specific genes, including SPO11, DMC1, MSH4, and MLH1, detected from a mycelial sample by real-time quantitative PCR, the nuclear behavior in mycelia was reconfirmed meiotic-like. CONCLUSION: Unlike other basidiomycetes where sex is largely restricted to basidia, Termitomyces maximizes sexuality at somatic stage, resulting in an ever-changing genotype composed of a myriad of coexisting heterogeneous nuclei in a heterokaryon. Somatic meiotic-like recombination may endow Termitomyces with agility to cope with termite consumption by maximized genetic variability.

Ophiodiaporthe cyatheae gen. et sp. nov., a diaporthalean pathogen causing a devastating wilt disease of Cyathea lepifera in Taiwan.

The scaly tree fern, Cyathea lepifera, in Taiwan has been devastated by an ascomycetous pathogen in recent years. This fungus resembles species of Diaporthe, but unlike anamorphs of Diaporthe that produce two types of conidia, its anamorph produces one conidium type. It is described herein as Ophiodiaporthe cyatheae gen. et sp. nov. Through pathogenicity tests, O. cyatheae was demonstrated to be the causal agent of the C. lepifera wilt disease. Of interest, sporulating structures of O. cyatheae have not been found on C. lepifera plants but in culture thus far. The mating system is homothallic. Phylogenetic analyses based on combined sequences of nSSU-rDNA, nLSU-rDNA, EF1-α-1 and RPB2 placed O. cyatheae in Diaporthaceae. Combined sequences of EF1-α-2 and TUB indicated that O. cyatheae had its origin within Diaporthe.

New and interesting penzigioid Xylaria species with small, soft stromata.

Six penzigioid Xylaria species that are characterized by small, discoid to pulvinate, soft stromata are included in this study. Xylaria albocinctoides, X. bicampaniformis and X. lechatii are described as new; Nummularia albocincta, Hypoxylon carabayense and H. discolor are moved to the genus Xylaria to form new combinations X. albocincta, X. carabayensis and X. discolor respectively. An identification key is provided for the major aggregates of Xylaria that harbor penzigioid species as well as the species of the X. frustulosa aggregate, to which the six studied penzigioid Xylaria species belong.

Xylaria coprinicola, a new species that antagonizes cultivation of Coprinus comatus in China.

The species known in China as the chicken-claw fungus is described as a new species, Xylaria coprinicola. This species is known as an antagonist of cultivation of the edible mushroom Coprinus comatus. Stromata of X. coprinicola are cylindrical, terminate in a sterile apex and arise in fascicles from a relative large submerged base; perithecia are immersed and have conspicuously conical ostiolar openings; ascospores are minute. Phylogenetic analyses based on combined partial sequences of rpb2, ß-tub and α-act genes showed that X. coprinicola is closely related to those Xylaria species exclusively associated with termite nests.

Production of a fungistatic substance by Pseudallescheria boydii isolated from soil amended with vegetable tissues and its significance.

Four fungal isolates that were able to use vegetable tissues for multiplication in soil were isolated and identified as Pseudallescheria boydii based on morphological characteristics and ITS sequence similarity. When grown in broth prepared from the same vegetable tissues used in soil amendment, all these isolates of P. boydii produced a substance capable of reducing the disease incidence of black leaf spot of spoon cabbage caused by Alternaria brassicicola and inhibiting the germination of A. brassicicola conidia. The substance, which was fungistatic, was very stable under high temperature and high or low pH value. It was soluble in polar solvents and insoluble in non-polar solvents. Molecular weight estimation and ion exchange ability tests suggest that the fungistatic compound has a molecular weight between 500 and 1,000 and has no charge on its molecule. Results from this study suggest the possession of a strong competitive saprophytic ability by P. boydii, which in turn may explain the widespread occurrence of this human pathogen in soil. Production of a fungistatic substance when P. boydii was grown in broth prepared from vegetable tissues suggests the importance of antibiotic production in its competitive saprophytic colonization of organic matters in soil.

Phylogenetic status of Xylaria subgenus Pseudoxylaria among taxa of the subfamily Xylarioideae (Xylariaceae) and phylogeny of the taxa involved in the subfamily.

To infer the phylogenetic relationships of Xylaria species associated with termite nests within the genus Xylaria and among genera of the subfamily Xylarioideae, beta-tubulin, RPB2, and alpha-actin sequences of 131 cultures of 114 species from Xylaria and 11 other genera of the subfamily were analyzed. These 11 genera included Astrocystis, Amphirosellinia, Discoxylaria, Entoleuca, Euepixylon, Kretzschmaria, Nemania, Podosordaria, Poronia, Rosellinia, and Stilbohypoxylon. We showed that Xylaria species were distributed among three major clades, TE, HY, and PO, with clade TE-an equivalent of the subgenus Pseudoxylaria-encompassing exclusively those species associated with termite nests and the other two clades containing those associated with substrates other than termite nests. Xylaria appears to be a paraphyletic genus, with most of the 11 genera submerged within it. Podosordaria and Poronia, which formed a distinct clade, apparently diverged from Xylaria and the other genera early. Species of Entoleuca, Euepixylon, Nemania, and Rosellinia constituted clade NR, a major clade sister to clade PO, while those of Kretzschmaria were inserted within clade HY and those of Astrocystis, Amphirosellinia, Discoxylaria, and Stilbohypoxylon were within clade PO.

Three new Xylaria species from Russian Far East.

Three new species of Xylaria, X. lepidota, X. primorskensis and X. sibirica were collected from Primorsky Territory in Russian Far East and neighboring areas. Xylaria primorskensis is a species with erect, stipitate stromata, whereas X. lepidota and X. sibirica produce stunted, sessile stromata. Cultures were obtained from X. primorskensis and X. sibirica. Xylaria sibirica formed a Xylocoremium anamorph in culture, while X. primorskensis remained sterile.

Theissenia rogersii sp. nov. and phylogenetic position of Theissenia.

Theissenia rogersii deviates from known Theissenia species primarily in having large ascospores with a thick wall layer and a unique configuration of two stromatal tissue types, one carbonaceous and the other fibrous. The carbonaceous tissue forms palisades on and beneath the perithecial layer as well as encasing individual perithecia, whereas the fibrous tissue fills the spaces between columns of the palisades as well as between encased perithecia. Phylogenetic analyses based on DNA sequences of beta-tubulin and alpha-actin genes placed Theissenia in the subfamily Hypoxyloideae among the genera that are characterized by having bipartite stromata (i.e. with the stromata differentiated into an outer dehiscing layer and an inner perithecium-bearing layer).

Xylaria species associated with nests of Odontotermes formosanus in Taiwan.

Nine species of Xylaria were collected in Taiwan from nests of Odontotermes formosanus, the only known macrotermitine termite in Taiwan. These include six newly described species, X. acuminatilongissima, X. atrodivaricata, X. brunneovinosa, X. griseosepiacea, X. intraflava and X. ochraceostroma, and three previously known species, X. cirrata, X. escharoidea and X. nigripes. We obtained cultures and ITS sequences from the nine species found in Taiwan and describe anamorphs for eight of them. Before the current study teleomorph-anamorph connections in the Xylaria species associated with termite nests have been established unequivocally in X. escharoidea only. Xylaria angulosa, X. fimbriata, X. kedahae, X. micrura, X. radicans, X. reinkingii and X. tolosa also are considered and annotated because they were reported to grow on ground and likely are associated with termite nests. Epitypifications are made for X. cirrata, X. escharoidea and X. nigripes. Xylaria sanchezii is considered a nomen dubium. Photographs are presented for most of the aforementioned species. A dichotomous key to 25 Xylaria species growing on termite nests or ground also is given.

New Hypoxylon and Nemania species from Costa Rica and Taiwan.

Six xylariaceous fungi, including two Hypoxylon taxa and four Nemania taxa, are described as new. They were collected from either Costa Rica or Taiwan. Two of the Nemania species--N. flavitextura and N. primolutea--were cultured and typical Geniculosporium anamorphs were produced.

Molecular phylogeny of Hypoxylon and closely related genera.

Phylogenetic relationships were inferred among several xylariaceous genera with Nodulisporium or nodulisporium-like anamorphs based on the analyses of beta-tubulin and alpha-actin sequences. One hundred nine cultures and three specimens of 83 representatives of these four genera were included in the study. Biscogniauxia taxa formed a well supported clade that was basal to the other taxa, while taxa of Hypoxylon and Daldinia comprised a large monophyletic group that contained two subclades. The first subclade encompassed Hypoxylon sect. Annulata and is accepted here as the new genus Annulohypoxylon. The second subclade contained taxa of Hypoxylon sect. Hypoxylon and Daldinia. Hypoxylon is restricted to include only those taxa in sect. Hypoxylon. Thirty-three epithets are made in Annulohypoxylon. Hypoxylon cohaerens var. microsporum is raised to the species level and accepted as A. minutellum. Hypoxylon polyporoideum is recognized as distinct from H. crocopeplum. Hypoxylon placentiforme is accepted as Daldinia placentiformis.

New Hypoxylon species and notes on some names associated with or related to Hypoxylon.

These new species of Hypoxylon are described: H. elevatidiscus, H. squamulosum, H. subalbum and H. vinosopulvinatum. A referenced list of all Hypoxylon species known to us described since 1996 is given and a key presented. Names associated with Hypoxylon that were not given in the Ju and Rogers monograph are annotated and diagnostic corrections of taxa discussed in that monograph are given.