Retiboletus, a new genus for a species-complex in the Boletaceae producing retipolides

Four New Species and a New Combination of Boletaceae (Boletales) from Subtropical and Tropical China

Previous studies have shown that boletes are abundant and diverse in China, especially in tropical and subtropical regions. In the present study, morphological, ecological, host relationship, and a four-locus (28S, tef1, rpb1, and rpb2) molecular phylogenetic analyses were used to study the family Boletaceae in subtropical and tropical China. Four new bluing species are described from three genera, viz. Boletellus verruculosus (Chinese name), Xerocomellus tenuis (Chinese name), Xer. brunneus (Chinese name), and Xerocomus zhangii (Chinese name). Moreover, the genus Nigroboletus is treated as a synonym of Xerocomellus, and a new combination, namely Xer. roseonigrescens (Chinese name), is proposed.

Exploring the Relationships between Four New Species of Boletoid Fungi from Northern China and Their Related Species

The family Boletaceae primarily represents ectomycorrhizal fungi, which play an essential ecological role in forest ecosystems. Although the Boletaceae family has been subject to a relatively global and comprehensive history of work, novel species and genera are continually described. During this investigation in northern China, many specimens of boletoid fungi were collected. Based on the study of their morphology and phylogeny, four new species, Butyriboletus pseudoroseoflavus, Butyriboletus subregius, Tengioboletus subglutinosus, and Suillellus lacrymibasidiatus, are introduced. Morphological evidence and phylogenetic analyses of the single or combined dataset (ITS or 28S, rpb1, rpb2, and tef1) confirmed these to be four new species. The evidence and analyses indicated the new species’ relationships with other species within their genera. Detailed descriptions, color photographs, and line drawings are provided. The species of Butyriboletus in China were compared in detail and the worldwide keys of Tengioboletus and Suillellus were given.

Retiboletus (Boletaceae) in northern Thailand: one novel species and two first records

Morphological characters and multi-gene phylogenetic analyses were used to identify Retiboletus specimens collected in northern Thailand. Retiboletus brevibasidiatus is described as new to science, whereas R. fuscus and R. nigrogriseus are reported for the first time from Thailand. Retiboletus brevibasidiatus produces medium-sized basidiomes, with a dark blonde to clay pileus and densely reticulate stipe mostly on the upper part with pale yellow to chrome yellow basal mycelium. It is difficult to separate R. brevibasidiatus from other closely related species on the basis of macroscopic characters. However, the new species can be distinguished by microscopic characters, mostly the shorter basidia. The macro- and micro-morphology of the R. fuscus and R. nigrogriseus collections from Thailand fit well with the previous descriptions of materials from China and Japan. Detailed descriptions, molecular phylogeny, and illustrations of the three species are provided.

Parvixerocomus matheranensis (Boletaceae), a new species from India

A new species of Parvixerocomus, P. matheranensis belonging to Boletoideae of Boletaceae is described and illustrated from tropical region of Maharashtra, India. P. matheranensis is morphologically distinguished by small basidiomes having ruby red pileus with concolorous stipe, yellow hymenophore that stains blue to blackish blue on bruising, elongate ellipsoid to cylindrical basidiospores with inconspicuous suprahilar depression, ventricose to clavate cheilocystidia, ventricose to lageniform pleurocystidia. Further, extensive phylogenetic analyses based on five gene markers (nrITS, nrLSU, rpb1, rpb2, tef1-α) confirmed that P. matheranensis is distinct from its closest taxa P. aokii and P. pseudoaokii and also from other members of Boletoideae.

Outstanding Pinkish Brown-Spored Neotropical Boletes: Austroboletus subflavidus and Fistulinella gloeocarpa (Boletaceae, Boletales) from the Dominican Republic

The occurrence of Austroboletus subflavidus and Fistulinella gloeocarpa is documented from the Dominican Republic. The latter species is reported for the first time outside its original locality in Martinique, extending the geographic range for this uncommon pinkish-spored bolete. A detailed morphological description is provided for each species and accompanied by color pictures of fresh basidiomes in habitat and line drawings of the main anatomical features. Both species represent independent lineages within their respective genera based on phylogenetic inference. In addition, A. subflavidus clusters in a sister lineage to the core Austroboletus clade (Austroboletus clade I) here named as Austroboletus clade II. In order to confirm the accuracy of species identification, their identity and relationships were subjected to multilocus phylogenetic analyses of three gene markers (ITS, nrLSU, RPB2) including genetic material already available in public databases. Austroboletus subflavidus is a widely distributed species in North and Central America, whereas F. gloeocarpa is apparently highly localized and seems to appear sparingly in the Dominican Republic, Martinque, and southern Florida. Comparisons with morphologically similar and molecularly inferred allied species are also presented and discussed.

New species of Retiboletus (Boletales, Boletaceae) from China based on morphological and molecular data

Species of the genus Retiboletus in China were investigated based on morphology and phylogenetic analysis of DNA sequences from the nuclear ribosomal large subunit (nrLSU) and the translation elongation factor 1-α gene (TEF1-α). Nine species were recovered from China, including two new and seven known species. The new species, namely Retiboletusater and R.sinogriseus, from southwestern and northeastern China respectively, are documented and illustrated in this paper. Retiboletusater is morphologically characterized by its black to grayish black pileus, white to grayish hymenophore, black to blackish stipe and white to grayish white context. Retiboletussinogriseus is morphologically characterized by its brown to grayish-brown pileus, yellow to grayish-yellow hymenophore, pale yellow to brownish stipe and yellow to brownish-yellow context. Descriptions and line drawings of these two novel species and their comparisons with allied taxa are presented.

Species and Geographical Origins Discrimination of Porcini Mushrooms Based on FT-IR Spectroscopy and Mineral Elements Combined with Sparse Partial Least Square-Discriminant Analysis

Misrecognition and toxic elements are two of several reasons responsible for food poisoning even death in the summer, a time when a great deal of edible mushrooms is celebrated in Southwestern China featured as complex environment conditions. It is highly important to identify the difference of chemical constituents in edible mushrooms at the regional-scale. In this study, Fourier transform infrared (FT-IR) spectroscopy and inductively coupled plasma mass spectrometry were applied to investigate organic matters and 18 mineral elements in porcini mushrooms of six species collected from 17 sampling sites in nine Yunnan cities. Classification models on the species, regions, and part levels were established using sparse partial least square-discriminant analysis and principal component analysis. At the species level and region level accuracies of greater than 92.1% and 92.8% was achieved, respectively, whereas on the part level caps and stipes were classified with 96.7% accuracy. One of the most popular mushrooms is Boletus edulis characterized by polysaccharide, lipid, and ribonucleic acid as well as several phenolic compounds. Temperature and precipitation show possible influences on accumulations of polysaccharides and ribonucleic acid. Furthermore, the most important elements of caps contributed the difference between two parts are copper (Cu), zinc (Zn), and phosphorus (P), whereas stipes instead by manganese (Mn) and cobalt (Co). These results demonstrated that FT-IR spectroscopy and elements contents provide information sufficient for classifying different porcini mushroom samples, which might be helpful for controlling food security and quality assessment of edible mushrooms.

New and noteworthy boletes from subtropical and tropical China

The morphology, ecology, and phylogenetic relationships of specimens of the family Boletaceae from subtropical and tropical China were investigated. Four species, Butyriboletushuangnianlaii, Lanmaoamacrocarpa, Neoboletusmultipunctatus, and Sutoriussubrufus, are new to science. Chalciporusradiatus and Caloboletusxiangtoushanensis are redescribed. Caloboletusguanyui is proposed to replace Boletusquercinus Hongo, an illegitimate later homonym. The recently described Tylopiluscallainus is synonymized with the Japanese Boletusvirescens, and the new combination T.virescens (Har. Takah. & Taneyama) N.K. Zeng et al. is proposed. Moreover, Neoboletus is treated as an independent genus based on evidence from morphology and molecular phylogenetic data in the present study, and many previously described taxa of Sutorius are recombined into Neoboletus: N.ferrugineus (G. Wu et al.) N.K. Zeng et al., N.flavidus (G. Wu & Zhu L. Yang) N.K. Zeng et al., N.hainanensis (T.H. Li & M. Zang) N.K. Zeng et al., N.obscureumbrinus (Hongo) N.K. Zeng et al., N.rubriporus (G. Wu & Zhu L. Yang) N.K. Zeng et al., N.sanguineoides (G. Wu & Zhu L. Yang) N.K. Zeng et al. , N.sanguineus (G. Wu & Zhu L. Yang) N.K. Zeng et al., and N.tomentulosus (M. Zang et al.) N.K. Zeng et al.

Spongispora temasekensis, a new boletoid genus and species from Singapore

Dipterocarp forests are a typical and widespread type of vegetation in tropical lowlands of southeast Asia that harbor a high diversity of ectomycorrhizal fungi, including boletes. Based on molecular and morphological characters, a unique bolete found in Singapore associated with the dipterocarp Hopea odorata was proven to represent a new species in the proposed new genus Spongispora. Phylogenetic analyses of five loci indicate that Spongispora is nested in the subfamily Leccinoideae of the Boletaceae, most closely related to an inclusive clade of Leccinum, Leccinellum, Octaviania, Rossbeevera, and Turmalinea. However, genetic distances between Spongispora and genera in Leccinoideae are mostly higher than that between any two known genera in this subfamily, which supports the proposal of a new genus. Spongispora temasekensis is characterized by a whitish to pale yellow hymenophore that stains brown where injured, coarsely reticulate stipe, interwoven trichodermial pileipellis, and broadly elliptical to ovoid basidiospores with sponge-like ornamentation perforated by irregular clefts, cracks, and warts under scanning electron microscopy. Morphological descriptions, illustrations, and comparisons with allied taxa are made, and a key to the genera of the subfamily Leccinoideae is provided.

The genus Retiboletus in China

Species of the genus Retiboletus (Boletaceae, Boletales) in China are investigated based on morphology and phylogenetic analyses of DNA sequences from nuc rDNA internal transcribed spacer (ITS) and partial 28S regions and sequences from the translation elongation factor 1-a gene (tef1a). Six lineages are recovered among the collections studied. Five of these are documented and presented in the present paper, including three new species and two new combinations. The remaining species is not described due to the paucity of material. The specimens from China identified as "R. ornatipes" or "R. retipes" are in fact R. sinensis or R. kauffmanii, those labeled "R. griseus" are either R. fuscus or R. pseudogriseus A key to all known taxa of the genus is provided. Phylogenetic relationships of taxa within Retiboletus are partially resolved. A preliminary biogeographical analysis shows that allied species of Retiboletus between eastern Asia and North/Central America are common but there are no Retiboletus species common to both continents. Species of Retiboletus in Japan and southern China are conspecific or closely related.

New Boletaceae taxa from Guyana: Binderoboletus segoi gen. and sp. nov., Guyanaporus albipodus gen. and sp. nov., Singerocomus rubriflavus gen. and sp. nov., and a new combination for Xerocomus inundabilis

Binderoboletus segoi gen. and sp. nov., Guyanaporus albipodus gen. and sp. nov. and Singerocomus rubriflavus gen. and sp. nov. (Boletaceae, Boletales, Basidiomycota) are described from the Pakaraima Mountains and adjacent lowlands of Guyana. Xerocomus inundabilis, originally described from the central Brazilian Amazon and based solely on the type collection, is redescribed from numerous collections from Guyana and transferred into Singerocomus. These boletes occur in Neotropical forests dominated by ectomycorrhizal trees in the genera Dicymbe (Fabaceae subfam. Caesalpinioideae), Aldina (Fabaceae subfam. Papilionoideae) and Pakaraimaea (Dipterocarpaceae). Three of the species were repeatedly found in a multiyear sporocarp survey in Dicymbe corymbosa-monodominant forest. Macromorphological, micromorphological, habitat and multilocus DNA sequence data are provided for each species. A molecular phylogenetic analysis based on a large taxon set across the Boletaceae justifies erection of the new genera.

Molecular phylogeny and taxonomy of the genus Veloporphyrellus

Veloporphyrellus is a genus known from North and Central America, southeastern Asia, and Africa. Because species of this genus are phenotypically similar to some taxa in several genera, such as Boletellus, Leccinum, Strobilomyces, Suillus and Tylopilus s.l. belonging to Boletales, its phylogenetic disposition has never been addressed. We analyzed four DNA regions, the nuclear ribosomal LSU and tef-1α, and the mitochondrial mtSSU and atp6 genes, to investigate the phylogenetic disposition of Veloporphyrellus. Although the monophyly of the genus and its systematic placement within the Boletaceae was well supported, its relationship to other genera was not resolved. Morphologically Veloporphyrellus is distinguished from other boletoid genera by the combination of the pinkish or grayish pink hymenophore, the membranous veil hanging on the pilea margin, the trichoderm-like pileus covering and the smooth basidiospores. Five species, including two new species and two new combinations, are described and illustrated. A key to the species of Veloporphyrellus also is provided.

Clarifying the butter Boletes: a new genus, Butyriboletus, is established to accommodate Boletus sect. Appendiculati, and six new species are described

The butter boletes (Boletus s.l. sect. Appendiculati) are an economically important group of ectomycorrhizal fungi whose basidiocarps have a yellow tube layer that often bruises blue, yellow reticulate stipe, mild flavor and firm yellow-tinged flesh that may or may not turn blue when exposed. Morphological characters and molecular data (ITS and LSU) place this group in a separate phylogenetic clade from Boletus sensu stricto. Here we establish a new genus, Butyriboletus, to accommodate 14 species of butter boletes that range from Asia to Europe, north Africa and North America. We recombine eight previously described butter bolete species and we describe six new species: four from western USA (Bu. persolidus, Bu. primiregius, Bu. autumnigius, Bu. querciregius) and two from Yunnan, China (Bu. yicibus, Bu. sanicibus).

Phylogenetic overview of the Boletineae

The generic and sub-generic relationships in the Boletineae (Boletales) were studied using nuclear large subunit (nuc-lsu), translation elongation factor 1-alpha (tef1), and DNA directed RNA polymerase largest subunit (RPB1). The Boletineae, with the exclusion of Hydnomerulius pinastri, was strongly supported and the status of the families Boletaceae and Paxillaceae is discussed. Members of the genus Boletus are found throughout the phylogeny, with the majority not closely related to the type species, Boletus edulis. Many of the traditional, morphologically defined genera are not supported as monophyletic and additional sampling and taxonomic revisions are needed. The majority of the Boletineae are confirmed or putatively ectomycorrhizal (ECM), but two putatively mycoparasitic lineages (one lineage of Buchwaldoboletus lignicola and Chalciporus piperatus and the second Pseudoboletus parasiticus) are strongly supported.

DNA sequence analyses reveal abundant diversity, endemism and evidence for Asian origin of the porcini mushrooms

The wild gourmet mushroom Boletus edulis and its close allies are of significant ecological and economic importance. They are found throughout the Northern Hemisphere, but despite their ubiquity there are still many unresolved issues with regard to the taxonomy, systematics and biogeography of this group of mushrooms. Most phylogenetic studies of Boletus so far have characterized samples from North America and Europe and little information is available on samples from other areas, including the ecologically and geographically diverse regions of China. Here we analyzed DNA sequence variation in three gene markers from samples of these mushrooms from across China and compared our findings with those from other representative regions. Our results revealed fifteen novel phylogenetic species (about one-third of the known species) and a newly identified lineage represented by Boletus sp. HKAS71346 from tropical Asia. The phylogenetic analyses support eastern Asia as the center of diversity for the porcini sensu stricto clade. Within this clade, B. edulis is the only known holarctic species. The majority of the other phylogenetic species are geographically restricted in their distributions. Furthermore, molecular dating and geological evidence suggest that this group of mushrooms originated during the Eocene in eastern Asia, followed by dispersal to and subsequent speciation in other parts of Asia, Europe, and the Americas from the middle Miocene through the early Pliocene. In contrast to the ancient dispersal of porcini in the strict sense in the Northern Hemisphere, the occurrence of B. reticulatus and B. edulis sensu lato in the Southern Hemisphere was probably due to recent human-mediated introductions.

The use of secondary metabolite profiling in chemotaxonomy of filamentous fungi

A secondary metabolite is a chemical compound produced by a limited number of fungal species in a genus, an order, or even phylum. A profile of secondary metabolites consists of all the different compounds a fungus can produce on a given substratum and includes toxins, antibiotics and other outward-directed compounds. Chemotaxonomy is traditionally restricted to comprise fatty acids, proteins, carbohydrates, or secondary metabolites, but has sometimes been defined so broadly that it also includes DNA sequences. It is not yet possible to use secondary metabolites in phylogeny, because of the inconsistent distribution throughout the fungal kingdom. However, this is the very quality that makes secondary metabolites so useful in classification and identification. Four groups of organisms are particularly good producers of secondary metabolites: plants, fungi, lichen fungi, and actinomycetes, whereas yeasts, protozoa, and animals are less efficient producers. Therefore, secondary metabolites have mostly been used in plant and fungal taxonomy, whereas chemotaxonomy has been neglected in bacteriology. Lichen chemotaxonomy has been based on few biosynthetic families (chemosyndromes), whereas filamentous fungi have been analysed for a wide array of terpenes, polyketides, non-ribosomal peptides, and combinations of these. Fungal chemotaxonomy based on secondary metabolites has been used successfully in large ascomycete genera such as Alternaria, Aspergillus, Fusarium, Hypoxylon, Penicillium, Stachybotrys, Xylaria and in few basidiomycete genera, but not in Zygomycota and Chytridiomycota.