Phylogenetic affinities of the sequestrate genus Rhodactina (Boletaceae), with a new species, R. rostratispora from Thailand

Pseudophylloporus Gen. nov. and Rubroleccinum Gen. nov., Two New Genera Revealed by Morphological and Phylogenetic Evidences in the Family Boletaceae from Subtropical China

Boletaceae, the largest and most diverse family of Boletales (Agaricomycetes and Basidiomycota), is both ecologically and economically important. Although many taxa have been described in China, the diversity of the family still remains incompletely understood. In the present study, Pseudophylloporus baishanzuensis gen. nov., sp. nov. and Rubroleccinum latisporus gen. nov., sp. nov. are proposed based on morphological and molecular phylogenetic analyses. These findings contribute to a deeper understanding of the diversity within the Boletaceae family.

Rostrupomyces, a new genus to accommodate Xerocomussisongkhramensis, and a new Hemileccinum species (Xerocomoideae, Boletaceae) from Thailand

A new genus, Rostrupomyces is established to accommodate Xerocomussisongkhramensis based on multiple protein-coding genes (atp6, cox3, tef1, and rpb2) analyses of a wide taxon sampling of Boletaceae. In our phylogeny, the new genus was sister to Rubinosporus in subfamily Xerocomoideae, phylogenetically distant from Xerocomus, which was highly supported as sister to Phylloporus in the same subfamily Xerocomoideae. Rostrupomyces is different from other genera in Boletaceae by the following combination of characters: rugulose to subrugulose pileus surface, white pores when young becoming pale yellow in age, subscabrous stipe surface scattered with granulose squamules, white basal mycelium, unchanging color in any parts, yellowish brown spore print, and broadly ellipsoid to ellipsoid, smooth basidiospores. In addition, Hemileccinuminferius, also from subfamily Xerocomoideae, is newly described. Detailed descriptions and illustrations of the new genus and new species are presented.

Four New Species of Strobilomyces (Boletaceae, Boletales) from Hainan Island, Tropical China

Strobilomyces, one of the most noticeable genera of Boletaceae (Boletales), is both ecologically and economically important. Although many studies have focused on Strobilomyces in China, the diversity still remains incompletely understood. In the present study, several collections of Strobilomyces from Hainan Island, tropical China were studied based on morphology and molecular phylogenetic analyses. Four species are described as new, viz. S. baozhengii, S. conicus, S. hainanensis, and S. pachycystidiatus. Detailed descriptions, color photos of fresh basidiomata, and line drawings of microstructures of the four species are presented.

The subfamily Xerocomoideae (Boletaceae, Boletales) in China

Xerocomoideae is an ecologically and economically important Boletaceae subfamily (Boletales) comprising 10 genera. Although many studies have focused on Xerocomoideae in China, the diversity, taxonomy and molecular phylogeny still remained incompletely understood. In the present study, taxonomic and phylogenetic studies on Chinese species of Xerocomoideae were carried out by morphological examinations and molecular phylogenetic analyses. Eight genera in Xerocomoideae, viz. Aureoboletus, Boletellus, Heimioporus, Hemileccinum, Hourangia, Phylloporus, Pulchroboletus, and Xerocomus were confirmed to be distributed in China; 97 species of the subfamily were accepted as being distributed in China; one ambiguous taxon was tentatively named Bol. aff. putuoensis; two synonyms, viz. A. marroninus and P. dimorphus were defined. Among the Chinese accepted species, 13 were newly described, viz. A. albipes, A. conicus, A. ornatipes, Bol. erythrolepis, Bol. rubidus, Bol. sinochrysenteroides, Bol. subglobosus, Bol. zenghuoxingii, H. squamipes, P. hainanensis, Pul. erubescens, X. albotomentosus, and X. fuscatus, 36 known species were redescribed, and the other 48 species were reviewed. Keys to accepted species of Aureoboletus, Boletellus, Heimioporus, Hemileccinum, Hourangia, Phylloporus, and Xerocomus in China were also provided. Taxonomic novelties: New species: Aureoboletus albipes N.K. Zeng, Xu Zhang & Zhi Q. Liang, A. conicus N.K. Zeng, Xu Zhang & Zhi Q. Liang, A. ornatipes N.K. Zeng, Xu Zhang & Zhi Q. Liang, Boletellus erythrolepis N.K. Zeng, R. Xue, S. Jiang & Zhi Q. Liang, Bol. rubidus N.K. Zeng, R. Xue, Y.J. Hao & Zhi Q. Liang, Bol. sinochrysenteroides N.K. Zeng, R. Xue & Kuan Zhao, Bol. subglobosus N.K. Zeng, R. Xue, S. Jiang & Zhi Q. Liang, Bol. zenghuoxingii N.K. Zeng, R. Xue, S. Jiang & Zhi Q. Liang, Hemileccinum squamipes N.K. Zeng, Chang Xu & Zhi Q. Liang, Phylloporus hainanensis N.K. Zeng, L.L. Wu, & Zhi Q. Liang, Pulchroboletus erubescens N.K. Zeng, Chang Xu & Zhi Q. Liang, Xerocomus albotomentosus N.K. Zeng, H.J. Xie, Chang Xu & Zhi Q. Liang, and X. fuscatus N.K. Zeng, H.J. Xie, Chang Xu & Zhi Q. Liang. Citation: Xue R, Zhang X, Xu C, Xie HJ, Wu LL, Wang Y, Tang LP, Hao YJ, Zhao K, Jiang S, Li Y, Yang YY, Li Z, Liang ZQ, Zeng NK (2023). The subfamily Xerocomoideae (Boletaceae, Boletales) in China. Studies in Mycology 106: 95-197. doi: 10.3114/sim.2022.106.03.

Boletaceae in China: Taxonomy and phylogeny reveal a new genus, two new species, and a new record

Boletaceae, the largest family in Boletales, has been attracted by mycologists in the world due to its diverse morphology and complex history of evolution. Although considerable work has been done in the past decades, novel taxa are continually described. The current study aimed to introduce three new taxa and one new record of Boletaceae from China. The morphological descriptions, color photographs, phylogenetic trees to show the positions of the taxa, and comparisons with allied taxa are provided. The new genus Hemilanmaoa is unique in the Pulveroboletus group, and Hemilanmaoa retistipitatus was introduced as the type species. It can be distinguished by its bluing basidioma when injured, a decurrent hymenophore, a stipe covered with distinct reticulations, and a fertile stipitipellis. Porphyrellus pseudocyaneotinctus is characterized by its pileipellis consisting of broadly concatenated cells and thin-walled caulocystidia in Porphyrellus. In Phylloporus, Phylloporus biyangensis can be distinguished by its hymenophores that change to blue when injured and yellow basal mycelium. Lanmaoa angustispora, as a new record, is first reported in Northern China. Internal transcribed spacer (ITS), 28S rDNA (28S), translation elongation factor 1-alpha (tef1-α), RNA polymerase II subunit 1 (rpb1), and RNA polymerase II subunit 2 (rpb2) were employed to execute phylogenetic analyses.

Retiboletus atrofuscus (Boletaceae, Boletales), a new species from China

Based on morphological and phylogenetic analyses, an ectomycorrhizal fungus collected from Jiangxi, China, is described as a new species. R. atrofuscus is morphological characterized by a dark gray to black pileus, white to pale yellowish white hymenophore, a grayish brown to pale yellow context, which turning orange-yellow to rusty yellow when injured, a prominently and coarsely white to pale yellow to black reticulation on upper 3/4 or entire stipe, grayish yellow to pale yellow to yellowish brown basidiospores in KOH with measuring (7-)7.5-13(-13.5) × (3-)3.5-5(-5.5) μm. Phylogenetic analysis results showed that R. atrofuscus formed an independent lineage within Retiboletus. Descriptions and hand drawings of the new species and comparisons with similar species are presented.

Rubinosporus auriporus gen. et sp. nov. (Boletaceae: Xerocomoideae) from Tropical Forests of Thailand, Producing Unusual Dark Ruby Spore Deposits

Rubinosporus, a new bolete genus from tropical forests of Thailand is introduced with R. auriporus as the type species. The genus is unique among Xerocomoideae in producing dark ruby spore deposits. It can be differentiated from all other Boletaceae genera by the following combination of characters: pileus surface evenly covered with matted tomentum; stipe surface with evenly scattered minute squamules; golden yellow tubular hymenophore, which is relatively thin especially when young; unchanging surfaces and context when bruised or cut; smooth, broadly ellipsoid basidiospores; and dark ruby spore deposits. The Boletaceae-wide and Xerocomoideae-wide phylogenetic analyses based on four-gene data sets (atp6, cox3, rpb2, and tef1) support Rubinosporus as monophyletic and places it in Boletaceae subfamily Xerocomoideae. Full descriptions and illustrations of the new genus and species are presented.

Tylocinum is no longer monotypic: Tylocinumbrevisporum sp. nov. (Boletales, Boletaceae) from northern Thailand

BACKGROUND

Tylocinum Y.C. Li & Zhu L. Yang 2016 is a Boletaceae genus belonging in subfamily Leccinoideae. It was described in 2016 from China and, prior to this study, it contained only one species, T.griseolum Y.C. Li & Zhu L. Yang 2016. During our survey of Boletaceae from Thailand, we collected some specimens that could be identified as a Tylocinum species, different from T.griseolum.

NEW INFORMATION

The bolete specimens, collected in forests dominated by Dipterocarpaceae and Fagaceae in northern Thailand, are described as Tylocinumbrevisporum Raghoonundon & Raspé sp. nov. Macroscopic and microscopic descriptions with illustrations are provided, as well as a 3-gene phylogeny, which confirms the new taxon's position in Tylocinum. Tylocinumbrevisporum differs from the only other known Tylocinum species (T.griseolum) by its brownish-grey colour, greyish-orange to brownish-orange colour change in the hymenophore when bruised, smaller pores (≤ 0.5 mm), longer tubes (up to 6 mm long), shorter and narrower basidiospores, longer and broader basidia and longer pleurocystidia relative to cheilocystidia. T.brevisporum is the second species from the genus Tylocinum and the only one to be found outside China thus far.

Four New Species of Hemileccinum (Xerocomoideae, Boletaceae) from Southwestern China

The genus Hemileccinum belongs to the subfamily Xerocomoideae of the family Boletaceae. In this study, phylogenetic inferences of Hemileccinum based on sequences of a single-locus (ITS) and a multi-locus (nrLSU, tef1-α, rpb1, rpb2) were conducted. Four new species, namely H. abidum, H. brevisporum, H. ferrugineipes and H. parvum were delimited and proposed based on morphological and molecular evidence. Descriptions and line-drawings of them were presented, as well as their comparisons to allied taxa. Our study shed new light on the recognition of the genus. The pileipellis of the species in this genus should mostly be regarded as (sub)epithelium to hyphoepithelium, because the pileipellis of most studied species here is composed of short inflated cells in the inner layer (subpellis) and filamentous hyphae in outer layer (suprapellis). The basidiospores of the studied species, including the type species, H. impolitum, have a warty surface.

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.

Multilocus phylogenies reveal three new truffle-like taxa and the traces of interspecific hybridization in Octaviania (Boletaceae, Boletales)

Among many convergently evolved sequestrate fungal genera in Boletaceae (Boletales, Basidiomycota), the genus Octaviania is the most diverse. We recently collected many specimens of Octaviania subg. Octaviania, including several undescribed taxa, from Japan and the Americas. Here we describe two new species in subgenus Octaviania, O. tenuipes and O. tomentosa, from temperate to subtropical evergreen Fagaceae forests in Japan based on morphological observation and robust multilocus phylogenetic analyses (nrDNA ITS and partial large subunit [LSU], translation elongation factor 1-α gene [TEF1] and the largest subunit of RNA polymerase II gene [RPB1]). Based on specimens from the Americas as well as studies of the holotype, we also taxonomically re-evaluate O. asterosperma var. potteri. Our analysis suggests that O. asterosperma var. potteri is a distinct taxon within the subgenus Octaviania so we recognize this as O. potteri stat. nov. We unexpectedly collected O. potteri specimens from geographically widespread sites in the USA, Japan and Colombia. This is the first verified report of Octaviania from the South American continent. Our molecular analyses also revealed that the RPB1 sequence of one O. tenuipes specimen was identical to that of a closely related species, O. japonimontana, and that one O. potteri specimen from Minnesota had an RPB1 sequence of an unknown species of O. subg. Octaviania. Additionally, one O. japonimontana specimen had an unusually divergent TEF1 sequence. Gene-tree comparison and phylogenetic network analysis of the multilocus dataset suggest that these heterogenous sequences are most likely the result of previous inter- and intra-specific hybridization. We hypothesize that frequent hybridization events in Octaviania may have promoted the high genetic and species diversity found within the genus.

Neoboletus infuscatus, a new tropical bolete from Hainan, southern China

Neoboletus infuscatus (Boletaceae, Boletales) is described as a new species from Yinggeling of Hainan Tropical Rainforest National Park, southern China. It is morphologically characterized by a large basidioma with a nearly glabrous, brownish yellow, yellowish brown to pale brown pileus, pores orangish red when young, yellowish brown to brown when old, context and hymenophore staining blue when injured, a yellow stipe with red punctuations, surfaces of the pileus and the stipe usually covered with a thin layer of white pruina when young. Phylogenetic analyses of DNA sequences from part of the 28S gene, the nuclear rDNA internal transcribed spacer (ITS) region, and part of the translation elongation factor 1-α gene (TEF1) also confirm that N. infuscatus forms an independent lineage within Neoboletus. Detailed morphological description, color photos of fresh basidiomata and line-drawings of microstructures are provided.

An Unexpectedly High Number of New Sutorius (Boletaceae) Species From Northern and Northeastern Thailand

Sutorius is a poroid genus in Boletaceae that typically has chocolate brown to reddish brown or purplish brown basidiomata with a finely scaly stipe and produces a reddish brown spore deposit. During the survey on diversity of boletes in Northern and Northeastern Thailand, several Sutorius collections were obtained. Combined evidence from morphology and phylogenetic analyses of a combined three-gene data set (atp6, tef1 and rpb2) of the Sutorius collections along with selected Boletaceae in the Pulveroboletus group indicated that Thai collections represent seven new Sutorius species. The analyses also indicated that Tylopilus maculatoides belongs in Sutorius. Therefore, the transfer of T. maculatoides to Sutorius is proposed. Full descriptions and illustrations of the seven new species and S. maculatoides are presented in this study. With the seven new species and the new combination, eight of the eleven described Sutorius species are known to occur in Northern and Northeastern Thailand, whereas only one species is known from each of two continents, the Americas and Australia.

Entoloma sequestratum, a new species from northern Thailand, and a worldwide key to sequestrate taxa of Entoloma (Entolomataceae)

Based on our study of the morphology and genetics of sporocarps collected in the mountains of northern Thailand, we herein describe Entoloma sequestratum as a new sequestrate member of the Entolomotaceae. This serves as the first report of a sequestrate member of the genus from Thailand. In addition, we provide a worldwide key to all of the described sequestrate members of the genus.

Continental-scale metagenomics, BLAST searches, and herbarium specimens: The Australian Microbiome Initiative and the National Herbarium of Victoria

PREMISE

Motivated to make sensible interpretations of the massive volume of data from the Australian Microbiome Initiative (AusMic), we characterize the soil mycota of Australia. We establish operational taxonomic units (OTUs) from the data and compare these to GenBank and a data set from the National Herbarium of Victoria (MEL), Melbourne, Australia. We also provide visualizations of Agaricomycete diversity, drawn from our analyses of the AusMic sequences and taxonomy.

METHODS

The AusMic internal transcribed spacer (ITS) data were filtered to create OTUs, which were searched against the National Center for Biotechnology Information Nucleotide database and the MEL database. We further characterized a portion of our OTUs by graphing the counts of the families and orders of Agaricomycetes. We also graphed AusMic species determinations for Australian Agaricomycetes against latitude.

RESULTS

Our filtering process generated 192,325 OTUs; for Agaricomycetes, there were 27,730 OTUs. Based on the existing AusMic taxonomy at species level, we inferred the diversity of Australian Agaricomycetes against latitude to be lowest between -20 and -25 decimal degrees.

DISCUSSION

BLAST comparisons provided reciprocal insights between the three data sets, including the detection of unusual root-associated species in the AusMic data, insights into mushroom morphology from the MEL data, and points of comparison for the taxonomic determinations between AusMic, GenBank, and MEL. This study provides a tabulation of Australian fungi, different visual snapshots of a subset of those taxa, and a springboard for future studies.

Expansion of the genus Imleria in North America to include Imleria floridana, sp. nov., and Imleria pallida, comb. nov

Imleria is a small genus of Boletaceae found primarily in the Northern Hemisphere characterized by the light to dark brown hymenophore that stains blue. In Florida, specimens of Imleria were collected that resembled I. badia, a species known primarily from northeastern North America and Europe. Five nuclear loci of these Florida specimens were sequenced and phylogenetically analyzed. A nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 (ITS) phylogeny of Imleria was generated using primarily uncultured environmental sequences to confirm ectomycorrhizal associations. Based on morphological and molecular data, we describe a new species, Imleria floridana. Results from these analyses also support the new combination Imleria pallida. A lectotype of I. pallida is also established from Charles H. Peck's original material. We discuss the distinguishing characters and species of Imleria found in North America and provide a key to the known worldwide species of Imleria.

Longistriata flava (Boletaceae, Basidiomycota) - a new monotypic sequestrate genus and species from Brazilian Atlantic Forest

A new monotypic sequestrate genus, Longistriata is described based on collections from the Neotropical forest of Atlantic forest in Paraíba, Northeast Brazil – an area known for its high degree of endemism. The striking features of this new fungus are the hypogeous habit, the vivid yellow peridium in mature basidiomes, broadly ellipsoid basidiospores with a distinct wall that is ornamented with longitudinal striations and lageniform cystidia with rounded apices. Phylogenetic analysis, based on LSU and tef-1α regions, showed that the type species, Longistriataflava, is phylogenetically sister to the monotypic sequestrate African genus Mackintoshia in Boletaceae. Together these two species formed the earliest diverging lineage in the subfamily Zangioideae. Longistriataflava is found in nutrient-poor white sand habitats where plants in the genera Coccoloba (Polygonaceae) and Guapira (Nyctaginaceae) are the only potential ectomycorrhizal host symbionts.

Revision of leccinoid fungi, with emphasis on North American taxa, based on molecular and morphological data

The leccinoid fungi are boletes and related sequestrate mushrooms (Boletaceae, Basidiomycota) that have traditionally been placed in Leccinum, Boletus, Leccinellum, and a handful of other less familiar genera. These mushrooms generally feature scabers or scaber-like dots on the surface of the stipe, and they are often fairly tall and slender when compared with other boletes. They are ectomycorrhizal fungi and appear to be fairly strictly associated with specific trees or groups of related trees. In the present study, we investigate the phylogenetic relationships among the leccinoid fungi and other members of the family Boletaceae using portions of three loci from nuc 28S rDNA (28S), translation elongation factor 1-α (TEF1), and the RNA polymerase II second-largest subunit (RPB2). Two DNA data sets (combined 28S-TEF1 and 28S-TEF1-RPB2), comprising sequences from nearly 270 voucher specimens, were evaluated using two different phylogenetic analyses (maximum likelihood and Bayesian inference). Five major clades were obtained, and leccinoid fungi appeared in four of them. Taxonomic proposals supported by our results, representing a broadly circumscribed Leccinum that includes several sequestrate genera, along with Leccinellum, are made.

Notes, outline and divergence times of Basidiomycota

The Basidiomycota constitutes a major phylum of the kingdom Fungi and is second in species numbers to the Ascomycota. The present work provides an overview of all validly published, currently used basidiomycete genera to date in a single document. An outline of all genera of Basidiomycota is provided, which includes 1928 currently used genera names, with 1263 synonyms, which are distributed in 241 families, 68 orders, 18 classes and four subphyla. We provide brief notes for each accepted genus including information on classification, number of accepted species, type species, life mode, habitat, distribution, and sequence information. Furthermore, three phylogenetic analyses with combined LSU, SSU, 5.8s, rpb1, rpb2, and ef1 datasets for the subphyla Agaricomycotina, Pucciniomycotina and Ustilaginomycotina are conducted, respectively. Divergence time estimates are provided to the family level with 632 species from 62 orders, 168 families and 605 genera. Our study indicates that the divergence times of the subphyla in Basidiomycota are 406–430 Mya, classes are 211–383 Mya, and orders are 99–323 Mya, which are largely consistent with previous studies. In this study, all phylogenetically supported families were dated, with the families of Agaricomycotina diverging from 27–178 Mya, Pucciniomycotina from 85–222 Mya, and Ustilaginomycotina from 79–177 Mya. Divergence times as additional criterion in ranking provide additional evidence to resolve taxonomic problems in the Basidiomycota taxonomic system, and also provide a better understanding of their phylogeny and evolution.

Two new Erythrophylloporus species (Boletaceae) from Thailand, with two new combinations of American species

Erythrophylloporus is a lamellate genus in the family Boletaceae that has been recently described from China based on E.cinnabarinus, the only known species. Typical characters of Erythrophylloporus are reddish-orange to yellowish-red basidiomata, including lamellae, bright yellow basal mycelium and smooth, broadly ellipsoid, ellipsoid to nearly ovoid basidiospores. During our survey on diversity of Boletaceae in Thailand, several yellowish-orange to reddish- or brownish-orange lamellate boletes were collected. Based on both morphological evidence and molecular analyses of a four-gene dataset (atp6, tef1, rpb2 and cox3), they were recognised as belonging in Erythrophylloporus and different from the already known species. Two new species, E.paucicarpus and E.suthepensis are therefore introduced from Thailand with detailed descriptions and illustrations. Moreover, two previously described Phylloporus species, P.aurantiacus and P.fagicola, were also revised and recombined in Erythrophylloporus. A key to all known Erythrophylloporus species is provided.

Cacaoporus, a new Boletaceae genus, with two new species from Thailand

We introduce a new genus, Cacaoporus, characterised by chocolate brown to dark brown basidiomata and hymenophore, tubes not separable from the pileus context, white to off-white basal mycelium, reddening when bruised, amygdaliform to ovoid spores and dark brown spore deposit. Phylogenetic analyses of a four-gene dataset (atp6, tef1, rpb2 and cox3) with a wide selection of Boletaceae showed that the new genus is monophyletic and sister to the genera Cupreoboletus and Cyanoboletus in the Pulveroboletus group. Two new species in the genus, C.pallidicarneus and C.tenebrosus are described from northern Thailand. Full descriptions and illustrations of the new genus and species are presented. The phylogeny also confirmed the reciprocal monophyly of Neoboletus and Sutorius, which further support the separation of these two genera.

Two new African siblings of Pulveroboletusravenelii (Boletaceae)

This paper sorts out the taxonomy of species affiliated with Pulveroboletusravenelii in the Guineo-soudanian and Zambezian woodlands of Africa. Morphological and genetic characters of African Pulveroboletus collections were studied and compared to those of North American and Asian species. A phylogenetic analysis showed that the African specimens form a subclade, sister to the Asian and American taxa. Although clamp connections have previously never been reported from Pulveroboletus, all specimens of the African subclade show very small clamp connections. Two new African species, Pulveroboletusafricanussp. nov. and P.sokponianussp. nov., are described and illustrated. Comments concerning morphology and identification, as well as distribution and ecology, are given for both species.

The genus Heimioporus in China

Species of Heimioporus (Boletaceae, Boletales) in China are investigated on the basis of morphology and molecular phylogenetic analyses of DNA sequences from the nuc rDNA internal transcribed spacer ITS1-5.8S-ITS2 region and nuc 28S rDNA D1-D2 domains (28S) and translation elongation factor 1-α gene (TEF1). Three species are recognized in China: H. conicus, sp. nov., H. gaojiaocong, sp. nov., and the previously described H. japonicus. Heimioporus xerampelinus, originally described from southwestern China, is synonymized with H. japonicus; specimens from China previously regarded as H. retisporus and H. subretisporus are confirmed to represent H. japonicus and H. gaojiaocong, respectively. A key to the Chinese taxa of the genus is provided. A preliminary biogeographical analysis shows that Heimioporus in East Asia and Southeast Asia/Australia are closely related. Heimioporus japonicus is a geographically widespread species occurring in East Asia and Southeast Asia; however, no taxa common to East Asia and Australia were uncovered.

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.