Phylogenetic origins and family classification of typhuloid fungi, with emphasis on Ceratellopsis, Macrotyphula and Typhula (Basidiomycota)

Abstract

Typhuloid fungi are a very poorly known group of tiny clavarioid homobasidiomycetes. The phylogenetic position and family classification of the genera targeted here, Ceratellopsis, Macrotyphula, Pterula sensu lato and Typhula, are controversial and based on unresolved phylogenies. Our six-gene phylogeny with an expanded taxon sampling shows that typhuloid fungi evolved at least twice in the Agaricales (Pleurotineae, Clavariineae) and once in the Hymenochaetales. Macrotyphula, Pterulicium and Typhula are nested within the Pleurotineae. The type of Typhula (1818) and Sclerotium (1790), T. phacorrhiza and S. complanatum (synonym T. phacorrhiza), are encompassed in the Macrotyphula clade that is distantly related to a monophyletic group formed by species usually assigned to Typhula. Thus, the correct name for Macrotyphula (1972) and Typhula is Sclerotium and all Typhula species but those in the T. phacorrhiza group need to be transferred to Pistillaria (1821). To avoid undesirable nomenclatural changes, we suggest to conserve Typhula with T. incarnata as type. Clavariaceae is supported as a separate, early diverging lineage within Agaricales, with Hygrophoraceae as a successive sister taxon to the rest of the Agaricales. Ceratellopsis s. auct. is polyphyletic because C. acuminata nests in Clavariaceae and C. sagittiformis in the Hymenochaetales. Ceratellopsis is found to be an earlier name for Pterulicium, because the type, C. queletii, represents Pterulicium gracile (synonym Pterula gracilis), deeply nested in the Pterulicium clade. To avoid re-combining a large number of names in Ceratellopsis we suggest to conserve it with C. acuminata as type. The new genus Bryopistillaria is created to include C. sagittiformis. The families Sarcomyxaceae and Phyllotopsidaceae, and the suborder Clavariineae, are described as new. Six new combinations are proposed and 15 names typified.

Introduction

Clavarioid fungi have club- or coral-shaped basidiomata with the hymenium fully exposed and include at least 540 species (Corner, 1950, Kirk et al., 2008). Phylogenetic studies have demonstrated that clavarioid basidiomata have arisen multiple times from ancestors with agaricoid or corticioid basidiomata in several lineages of Basidiomycota (Pine et al., 1999, Dentinger and McLaughlin, 2006), but molecular phylogenies of clavarioid fungi and allied taxa are far from being complete. Clavarioid lineages are known to have evolved in the Agaricales, Cantharellales, Gomphales, Hymenochaetales, Russulales, Thelephorales and Trechisporales among the Agaricomycetes (Pine et al., 1999, Hibbett and Binder, 2002, Hibbett, 2004, Dentinger and McLaughlin, 2006, Birkebak et al., 2013), but fully supported multigene phylogenies are lacking in most cases and details as to how transitions to a clavarioid basidioma type have occurred are vague. A more comprehensive taxon sampling and addition of more molecular markers is still needed in many groups, including clavarioid fungi, to better understand the evolution of basidioma configuration.

In this study, we target a group of clavarioid fungi with tiny basidiomata (Fig. 1A–K), here referred to as “typhuloid” following e.g. Corner, 1950, Petersen, 1974, Petersen et al., 2014, and Olariaga et al. (2016). Corner (1950: 145) characterised typhuloid fungi by their: i) small basidiomata and limited growth, ii) distinct stipe and fertile head, iii) simple hymenium, iv) epiphytic habitat on wood, stems or leaves, rather than being terricolous, v) smooth, white ellipsoid spores, vi) monomitic, generally clamped hyphae, and vii) agglutination of the hyphae on the surface of the stem. Three genera were regarded as typhuloid, Typhula, Pistillaria and Pistillina (Corner 1950), and were separated from pteruloid fungi (Deflexula, Pterula) with a dimitic hyphal system and from Ceratellopsis with highly reduced clavarioid basidiomata with generally sterile apices. Berthier (1976), in his monograph “Typhula and allied genera”, treated typhuloid fungi in a broader sense and considered Ceratellopsis, Macrotyphula, Pterula and Typhula to represent a natural group without proposing any family classification. Hirticlavula elegans, a member of Clavariaceae producing minute, hairy basidiomata, has also been considered somewhat typhuloid (Petersen et al. 2014), and limits between typhuloid fungi and other reduced clavarioid fungi are not always clear. Typhuloid fungi represent one of the most overlooked, poorly known and enigmatic groups of homobasidiomycetes. The family classification of these fungi is uncertain or based on weakly supported phylogenies with a very limited taxon sampling. Macrotyphula and Typhula were previously placed in Clavariadelphaceae (Corner, 1970, Hawksworth et al., 1995), but recent classifications place both genera in Typhulaceae together with Sclerotium (Kirk et al., 2008, Knudsen and Vesterholt, 2012). The family classification of Ceratellopsis is even more controversial. Initially included by Corner (1970) in Clavariadelphaceae, Jülich (1982) accommodated it in Typhulaceae. Hawksworth et al. (1995) and Begerow et al. (2018), probably following Corner, included it in Gomphaceae, although Ceratellopsis lacks the synapomorphic characters of this family, such as pistillarin, ampullate septa and cyanophilous, ornamented spores (Hosaka et al. 2006). As no molecular data of Ceratellopsis has been available, its phylogenetic relationships and classification have remained doubtful. Besides the above-mentioned genera treated by Berthier (1976), Mucronella and Hirticlavula, both producing tiny clavarioid basidiomata, have been assigned to the Clavariaceae based on molecular data (Birkebak et al., 2013, Petersen et al., 2014). Regardless of their phylogenetic origin, all typhuloid fungi share similar taxonomic problems. For many species of those genera only the type specimen or very few collections are known, species limits are unclear and distribution data are meagre. Molecular data of only a handful of species are available in public sequence repositories and the high morphological diversity of the group remains poorly sampled.

Fig. 1.

Diversity of typhuloid and pleurotoid fungi suggested to be closely related to Typhula. A.Macrotyphula fistulosa s.l. (IO.14.214, ARAN-Fungi). B.Macrotyphula juncea (IO.16.53, S). C.Typhula phacorrhiza, current type of Typhula (ARAN-Fungi 7446), here combined in Macrotyphula. D. Compressed sclerotium of T. phacorrhiza (ARAN-Fungi 7446). E.Typhula incarnata, showing sclerotia at the base (IO.14.92, S), proposed conserved type of Typhula. F.Typhula uncialis (IO.14.94, S, UPS), type of Gliocoryne. G.Typhula crassipes (IO.14.83, S, UPS). H.Typhula subhyalina (IO.15.06, S), type of Pistillina and Dacryopsella. I.Typhula erythropus (IO.16.83, ARAN-Fungi). J.Ceratellopsis aff. aculeata (ARAN-Fungi 11746). K.Pterulicium gracile (IO.14.142, S, UPS). L.Phyllotopsis nidulans (ARAN-Fungi). M.Pleurocybella porrigens (BIO-Fungi 13431). N.Sarcomyxa serotina (IO.14.130, S, UPS). Photographs I. Olariaga, except L by J.I. Iturrioz.

Typhula and segregated genera, Macrotyphula, and phylogenetic position of Typhulaceae

The phylogenetic position of Typhulaceae has been inferred from only two species, Typhula phacorrhiza and Macrotyphula fistulosa, type of Typhula and Macrotyphula, respectively. Through analyses of a 5-locus dataset, Matheny et al. (2006) recovered Typhulaceae in the hygrophoroid clade (Agaricales) with phylogenetic confidence, as sister to the Hygrophoraceae in a supported clade encompassing Pterulaceae and members of two pleurotoid agaric genera (Sarcomyxa serotina and Phyllotopsis spp.) (Fig. 1L–N). Binder et al. (2010), employing a broader taxon sampling of the Agaricomycetes, recovered also Typhulaceae as sister to Hygrophoraceae but without support, while Pterulaceae was supported as closely related to Stephanosporaceae instead (Binder et al. 2010). Other studies have not been able to confirm or reject the inclusion of Typhulaceae in the hygrophoroid clade, but recovered agaric or pleurotoid genera, such as Phyllotopsis, Pleurocybella, Tricholomopsis, as sister taxa of Typhulaceae with phylogenetic confidence (Dentinger and McLaughlin, 2006, Lodge et al., 2014). Dentinger et al. (2016) resolved for the first time several deep nodes of the Agaricales through a 208-locus dataset containing 35 taxa of Agaricales, and found that the hygrophoroid clade, as defined by Matheny et al. (2006), was paraphyletic. Also, Hygrocybe conica (Hygrophoraceae) was recovered as sister to the Clavariaceae, while Pterulaceae (Pterula multifida; recovered in the hygrophoroid clade by Matheny et al. (2006)), appeared in a branch with Pleurotus ostreatus. Thus, the results by Dentinger et al. (2016) question the inclusion of the Typhulaceae in the hygrophoroid clade. In addition to its uncertain phylogenetic position, the monophyly of Typhulaceae has not been tested appropriately.

Two genera, Typhula and Macrotyphula, are currently accepted in Typhulaceae (e.g. Berthier, 1976, Knudsen and Vesterholt, 2012). Macrotyphula differs from Typhula in having large, yellow-brown basidiomata (30–300 mm) that never arise from sclerotia and non-amyloid spores (Berthier 1976). In contrast, Typhula includes species with smaller basidiomata (generally under 10 mm long) that often arise from sclerotia and usually have amyloid spores. Some Typhula species are important plant pathogens that cause economic loss in cereal crops (e.g. Ekstrand 1955). These are popularly known as “snow moulds”, producing symptoms known as “Typhula blight” (Matsumoto et al., 2001, Hoshino et al., 2008). Several economically important species like T. incarnata and T. ishikariensis have been subjected to extensive research on their ecology, physiology and genetics (e.g. Matsumoto, 1992, Vergara et al., 2004, Blunt et al., 2015, Chang, 2015, Koch, 2016). Generic limits of Typhula are not fully delineated and lack a complete consensus. Probably due to the fact that its species show diverse basidioma morphologies, sclerotial anatomy and asexual morph states (Berthier 1976), a number of genera have been segregated from Typhula, such as Cnazonaria, Dacryopsella, Gliocoryne, Phacorhiza, Pistillaria, Pistillina, Scleromitra and Sphaerula. These genera have been used to a certain extent. Of these, Corner (1950) recognised Pistillaria (with Cnazonaria, Gliocoryne, Scleromitra and Sphaerula in synonymy), Pistillina and Typhula (with Phacorhiza in synonymy). Donk (1954) adopted also Pistillaria, Typhula and Pistillina, and further synonymised Dacryopsella under Pistillina. Pistillaria has been recognised generally based on a ceraceous consistency of the fresh fruitbodies, horny when dried, and the absence of sclerotia (Corner, 1950, Corner, 1970, Pilát, 1958), but generic limits between Pistillaria and Typhula have been long debated (Corner, 1950, Bourdot and Galzin, 1928, Donk, 1954, Berthier, 1976). Pistillina has been distinguished by basidiomata with a globose fertile part (Corner 1950). Berthier (1976), after examining extensive material and type specimens available, merged all these genera under Typhula (Sphaerula, Scleromitra and Dacryopsella were not treated in the monograph), but recognised Cnazonaria, Gliocoryne, Pistillaria and Pistillina as subgenera. After the publication of Berthier's monograph, a few authors have continued to use Pistillaria and Pistillina at the generic level (Shiryaev and Kotiranta, 2007, Kaygusuz and Çolak, 2017, Begerow et al., 2018, Petersen and Læssøe, 2019). Recently, the new monotypic genus Tygervalleyomyces was described in Typhulaceae based on analyses of the 28S region (Crous et al. 2017). The asexual morph of Tygervalleyomyces podocarpi, the only known morph, is similar to the asexual morph of Typhula crassipes (Berthier 1976, as Typhula corallina) in the cylindrical conidia with a truncate base, and in fact these two species have highly similar 28S sequences (98 %) and nested within a larger highly supported clade containing other Typhula species (Crous et al. 2017). In view of this, the status of Tygervalleyomyces needs to be re-evaluated in the light of a phylogeny with a broader sampling of Typhula species. Olariaga & Salcedo (2013) synonymised Typhula and Macrotyphula due to the fact that T. phacorrhiza formed a monophyletic group with Macrotyphula in previous analyses (Pine et al., 1999, Hibbett, 2007), as well as morphological similarities. The designation of T. phacorrhiza as lectotype of Typhula by Donk (1933) has been considered unfortunate (Berthier, 1976, Olariaga, 2009, Olariaga and Salcedo, 2013), because T. phacorrhiza, with long filiform basidiomata and unique compressed sclerotia, is an atypical species in Typhula (Remsberg, 1940, Corner, 1950, Berthier, 1976). In fact, T. phacorrhiza shares many features with M. fistulosa, i.e. the pale brown, large basidiomata, the stipe surface with thin hyphae and caulotrichomes, the basal tomentum formed by thick-walled, scarcely septate hyphae and the presence of a hyaline, striped encrustation on the medulla hyphae (Olariaga & Salcedo 2013). Molecular phylogenetic analyses show that these species are closely related and nested in the Agaricales (Binder et al. 2010). Nevertheless, taxon sampling in phylogenetic studies of Typhulaceae is extremely poor and the synonymy of Typhula and Macrotyphula needs to be further explored.

The type of Sclerotium is conspecific with the type of Typhula

The genus Sclerotium, also included in Typhulaceae (Kirk et al. 2008), is currently treated as an artificial genus that accommodates fungi producing sclerotia but not, or rarely, a sexual morph (Xu et al. 2010). Tode (1790) included originally eight species in Sclerotium, of which Fries (1821) treated S. complanatum in the first place and Clements & Shear (1931: 411) thus selected this species as the type of Sclerotium. A number of authors, especially during the XIX^th century, described numerous species in Sclerotium, including ascomycetous and basidiomycetous fungi (e.g. Fries, 1822, Léveillé, 1843, Duby, 1830, Desmaziéres, 1848, Rostrup, 1866), and numerous plant pathogens (Xu et al. 2010). Until now, 464 names have been described or combined in Sclerotium (Index Fungorum, viewed on 11 June 2019) and it is evident that species assigned to Sclerotium have multiple evolutionary origins, but very few attempts to disassemble it have been made (Xu et al. 2010). With the end of the asexual-sexual morph dual nomenclature, many names in Sclerotium may turn out to have priority over species names in use. Several early authors observed that some Sclerotium species appeared in connection or directly attached to basidiomata of Typhula species (e.g. Berkeley, 1837, Léveillé, 1843 (as Clavaria), Rostrup 1866). Sclerotium complanatum, type of Sclerotium, is characterised by producing compressed sclerotia attached to the substrate by a small stalk (Tode 1790) which conform to those produced by T. phacorrhiza (Berkeley, 1837, Rostrup, 1866, Schröter, 1889). Thus, it is generally accepted that S. complanatum is a synonym of T. phacorrhiza (Xu et al., 2010, Kaygusuz and Çolak, 2017), although only Remsberg (1940) has proposed this synonymy according to our search. Other authors attributed S. complanatum to the sclerotial morph of T. gyrans (Fries, 1874, Corner, 1950, Donk, 1962), but this view appears to have been abandoned. In the meantime, the taxonomic identity of S. complanatum has not been reassessed and the name remains untypified. As currently asexual names compete with sexual names for priority, the possible synonymy of S. complanatum and T. phacorrhiza would make Sclerotium and Typhula taxonomic synonyms, and all Typhula names in use, including those being applied to economically important plant pathogens, would have to be transferred to the older and equally sanctioned genus Sclerotium. Examining in depth the taxonomic concept of S. complanatum and proposing a typification is thus of paramount importance to deal with a possible scenario of undesirable nomenclatural changes.

The poorly known genus Ceratellopsis, a possible earlier synonym of Pterulicium

Ceratellopsis differs from Typhula in having minute filiform basidiomata with a sterile apex and a non-corticate stipe (Corner, 1950, Berthier, 1976). Short basidia up to 20 μm have also been suggested to be a diagnostic character (Jülich 1982). Pterulicium gracile, called Pterula gracilis until very recently (Leal-Dutra et al. 2020), strongly resembles species of Ceratellopsis because of its minute white basidiomata with a sterile apex, at least at early stages of development (Corner, 1950, Berthier, 1976), but it differs microscopically in having skeletal hyphae, typical for Pterulaceae, 2-spored basidia and no stipe (Corner, 1950, Olariaga, 2009). Furthermore, we have made collections with very minute basidiomata with a clearly delimited stipe suggesting Ceratellopsis, but having skeletal hyphae as typical in Pterulaceae. Limits between Ceratellopsis and Pterulaceae, thus, are not always clear-cut.

As pointed out by Donk, 1954, Konrad and Maublanc, 1937 introduced Ceratellopsis based on the validly published but illegitimate Ceratella Pat. (Patouillard 1887; later homonym of Ceratella Hook. f. 1844) and explicitly indicated Ceratellopsis queletii as the type of Ceratellopsis. While Donk (1954) followed this typification, Corner (1950), noted that C. queletii might represent a rudimentary Pterula, and he selected instead Ceratellopsis aculeata as type so that Ceratellopsis could be used with certainty and not reduced to a synonym of Pterula. This choice, nevertheless, is not permissible (Turland et al. 2018; Art. 7.8) since the original type indication of Ceratellopsis by Konrad & Maublanc (1937) is unequivocal and irrevocable. Also, Olariaga (2009) proposed tentatively that C. queletii might be a synonym of Pterulicium gracile, but up to present, no consistent and stable interpretation of C. queletii has been provided and the taxonomic status of Ceratellopsis remains unresolved. Twenty-four names have been described or combined in Ceratellopsis, but several of them represent P. gracile (Berthier 1976) or Typhula species.

The confirmation that C. queletii, type of Ceratellopsis, is a synonym of P. gracile would have important consequences in the classification of Pterulaceae. The family, centered on the genus Pterula, has included several clavarioid genera with a dimitic hyphal system (Corner 1970). Based on molecular studies, four resupinate genera (Aphanobasidium, Coronicium, Merulicium, Radulomyces; Larsson, 2007, Larsson et al., 2004) and the polyporoid Radulotubus (Zhao et al. 2016) were later transferred to Pterulaceae. In the light of analyses of the ITS, 28S and RPB2 regions, employing a rich taxon sampling of the Pterulaceae, Leal-Dutra et al. (2020) elucidated generic limits in the family. This study discovered Pterula to be polyphyletic and splits its species into the new genus Myrmepterula, Phaeopterula and Pterulicium, leaving in Pterula sensu stricto a handful of species around Pterula plumosa. Deflexula was shown to be paraphyletic because some species nest in the Pterula clade, while the type D. fascicularis is in the Pterulicium clade. In total, 46 names earlier treated in Pterula and Deflexula were combined in Pterulicium, a genus up to then monospecific. Pterula gracilis was found to belong to the Pterulicium clade and accordingly combined as Pterulicium gracile. In this framework, would the synonymy between C. queletiti and P. gracile be confirmed, the name Ceratellopsis (1937) would have priority over Pterulicium (1950). Thus, the identity of C. queletii needs urgent clarification.

In the present study, we expand the taxon sampling of typhuloid fungi based on the multigene datasets used by Matheny et al. (2006) and Binder et al. (2010). With these data, our main goals were to: 1) provide a robust phylogenetic hypothesis for typhuloid fungi, especially for T. phacorrhiza (type of Typhula), types of genera segregated from Typhula, Sclerotium complanatum (type of Sclerotium) and Ceratellopsis species; 2) test the monophyly of Typhula; 3) assign typhuloid fungi to appropriate families; and 4) propose an updated nomenclature in the light of a robust multigene phylogeny.

Material and methods

Molecular techniques

DNA was extracted from fresh (stored in 1 % SDS extraction buffer) basidiomata, using a DNeasy Plant Mini Kit (Qiagen) according to the manufacturer’s instructions. The following six gene regions were amplified: 1) nu5.8S rDNA, the 5′ end of the nuclear 28S rDNA (spanning domains D1–D2), part of the nuSSU rDNA (ca. 1 600 bp), RPB1 (900 bp; A–C), RPB2 (5–7 region, ca. 1 100 bp) and EF-1α (1 100 bp). The ITS (ITS1-5.8S-ITS2) and 28S regions were amplified in one piece using the primers ITS5-LR7, or otherwise as separate pieces: ITS using ITS5-ITS4, (White et al. 1990); and 28S using LR0R-LR5 (or LR3) and LR3R-LR7 (Vilgalys & Hester 1990). The same primers were used for sequencing. The ITS was sequenced using the primers ITS1-ITS4 and/or in a few instances ITS5, 5.8S and ITS3. The SSU region was amplified in one piece employing primers NS1-NS8 or in two pieces using NS1-NS4 and NS3-NS8 (White et al. 1990). PCR products of the RPB1 region were obtained using gRPB1-A (Stiller & Hall 1997) and fRPB1-C rev primers (Matheny et al. 2002). The sequence spanning RPB2 regions 5–7 was amplified in one piece, using fRPB2-5F and bRPB2-7R, or if required, in two pieces with primers fRPB2-5F-gRPB2-6R and bRPB2-6F-bRPB2-7R (Liu et al., 1999, Matheny, 2005). For samples that did not succesfully amplify or for sequencing, Typhula-specific primers were designed for the RPB2 region and used in different combinations (Table 1). The EF-1α region was PCR amplified and sequenced employing 983F and 2218R primers (Rehner & Buckley 2005). Typhula-specific primers of the EF-1α region were designed and used for PCR amplification and sequencing of problematic samples (Table 1). PCR amplifications were performed using Illustra™ Hot Start Mix RTG PCR beads (GE Healthcare, UK) in a 25 μL volume, containing 3 μL of genomic DNA, 10 μM of each primer and distilled water. PCRs were conducted in Applied Biosystems GeneAmp® PCR System 9700 and 2720 Thermal Cyclers. Amplifications were performed using the following program: initial denaturation at 95 °C for 5 min, followed by 35–40 cycles of 95 °C for 45–60 s, 52–58 °C for 50 s, 72 °C for 1 min, followed by a final extension at 72 °C for 10 min. PCR amplifications of protein-coding genes follow O’Donnell et al. (2011, RPB1) and Hansen et al. (2013, RPB2, EF-1α). PCR products were purified using the enzymatic method Exo-sap-IT (USB Corporation, Santa Clara, California, USA). When multiple bands were amplified in the RPB1 and RPB2 regions, PCR products were size-fractionated in a 1 % agarose gel, stained with GelRed™ (Biotium Inc.), visualised over a UV trans-illuminator, excised and purified using QIAquick spin columns (Qiagen). Purified PCR products were sequenced at Macrogen Europe service (www.macrogen.com).

Table 1.

Newly designed Typhula-specific primers for the RPB2 and EF-1α (5’–3’) regions.

Locus	Primer	Sequence	PCR	Sequencing
EF-1α	1007F-Typh	SCGAGGAYCGTTTCAACGAG		X
EF-1α	1447F-Typh	GCATGCCHTGGTWCAAGG	X	X
EF-1α	1825F-Typh	GAACGTVTCCGTYAAGGAYA		X
EF-1α	2100R-Typh	ATKGGCTTGGARGGRACRA		X
RPB2	RPB2-5Fint-Typh	AARAARCGDYTNGAYYTSGC		X
RPB2	RPB2-6F-Typh	TGGGGAYTGGAGTCGTTGGA	X	X
RPB2	RPB2-6R-Typh	TCCAACGACTCCARTCCCCA	X	X
RPB2	RPB2-7Rint-Typh	TASGTGTTACGAGGRGACT		X

Type specimens, taxon and molecular sampling

Type specimens of small typhuloid fungi available at E, FH, M, PC, S and UPS herbaria were examined: Ceratella ferryi, Ceratellopsis carestiae, C. rickii, C. acuminata, C. equiseticola, Clavaria aculina, C. microscopica, Pistillaria attenuata, P. juncicola, Pterulicium gracile, Typhula brunaudii, T. crassipes, T. sclerotioides, T. sphaeroidea, T. subhyalina and T. uncialis. Material deposited in G (customs blocked the loan), PAD (not available on loan) and SAPA (several contact attempts unsuccessful) could not be examined. The notation “!” indicates that type or other original material was examined by us. Cultures of the taxa collected and described in this study were deposited in the CBS-KNAW culture collection at the Westerdijk Fungal Biodiversity Institute.

For molecular analyses, types and other species of genera considered to be typhuloid or assigned to Typhulaceae were sampled, namely Ceratellopsis, Macrotyphula, Pterulicium gracile, Typhula s.l. and Sclerotium. A collection identified as C. acuminata, with skeletal hyphae, was included to test the limits between Ceratellopsis and Pterula. Nucleotide sequences were aligned in the six-gene dataset (nu5.8S rDNA, nu28S rDNA, nu18S rDNA, RPB1, RPB2 and EF-1α) assembled by Binder et al. (2010; TreeBASE no. S10185), in order to preliminarily explore their phylogenetic affinities. Nucleotide sequences were aligned in Aliview (Larsson 2014). This alignment was subjected to a maximum likelihood (ML) analysis using the “RAxML HPC2 on XSEDE” tool (Stamatakis 2014) in the CIPRES Science Gateway (Miller et al. 2010), starting from a random tree. A GTR-GAMMA model with four rate categories was selected for tree inference. For branch confidence, 1 000 ML bootstrap replicates were conducted with a GTRCAT model (ML-BP). Targeted typhuloid taxa nested in Agaricales (ML-BP 92 %), except for Ceratellopsis sagittiformis that was placed in Hymenochaetales. Based on this analysis, a first 6-locus (5.8S, 28S, 18S, RPB1, RPB2, EF-1α) dataset (the Agaricales matrix) was prepared to phylogenetically place typhuloid fungi among the Agaricales. Three taxa, Amylocorticium cebennense, Plicaturopsis crispa and Serpulomyces borealis, were included as outgroup for rooting purposes based on previous studies (Binder et al. 2010). A second dataset with the same molecular markers (the Pleurotineae matrix) included Typhulaceae and closely related families, with a more species-inclusive sampling than in the Agaricales matrix. Cantharocybe gruberi was used as an outgroup based on analyses of the Agaricales matrix. A third 28S alignment (the Clavariaceae matrix) was constructed based on Birkebak et al. (2013) to infer phylogenetic relationships of Ceratellopsis within the Clavariaceae, and employed Anomoporia bombycina, A. kamtschatica and Podoserpula pusio as outgroup taxa. A fourth 4-locus (5.8S, 28S, 18S, RPB2) dataset (the Hymenochaetales matrix) was assembled to further explore phylogenetic relationships of C. sagittiformis within the Hymenochaetales. Sequences of Calocera cornea were set as outgroup.

Sequence alignment and phylogenetic analyses

Sequences were edited and assembled using Sequencher v. 4.10.1 (Gene Codes Corp., Ann Arbor, MI) and deposited in GenBank (Table 2). Additional sequences were downloaded from GenBank and from the following genomes through the MycoCosm portal (Grigoriev et al. 2014): Agaricus bisporus, Coprinopsis cinerea (Muraguchi et al. 2015), Laccaria bicolor (Martin et al. 2008), Onnia scaura, Phellinus ferrugineofuscus, Plicaturopsis crispa (Kohler et al. 2015), Pterulicium gracile (Varga et al. 2019, deposited as Pterula gracilis), Radulomyces confluens and Trichaptum abietinum (Table 2). Nucleotide sequences were aligned manually using Aliview (Larsson 2014). Protein-coding genes were translated to amino acids to determine intron positions. In order to check gene-tree congruence, each individual gene-region was analysed using a ML approach, as explained above. Gene congruence was assessed manually by comparing supported clades among single-gene genealogies (Mason-Gamer & Kellogg 1996). Clades were considered in conflict if a supported clade (ML-BP >70 %) for one marker was contradicted with significant support by another one. Since no conflict was detected, markers were concatenated in the Agaricales, Typhulaceae and Hymenochaetales alignments. Introns were excluded and the third codon position was partitioned in the protein-coding genes (RPB1, RPB2 and EF-1α). Each matrix was subjected to ML and Bayesian analyses. ML analyses were conducted as explained above. Bayesian analyses were implemented in MrBayes v. 3.2.6 (Ronquist et al. 2012), using two parallel runs of eight Metropolis-coupled Markov chain Monte Carlo (MCMCMC) chains for 30 M generations, starting from a random tree, and sampling one tree every 1 000^th generation from the posterior distribution. Substitution models were sampled across the GTR space during the MCMC simulation (Ronquist et al. 2012). Stationarity was assumed when average standard deviation of split frequencies fell below 0.01. A burn-in sample of 30 000 trees was discarded. To assess branch confidence, a 50 % majority rule consensus tree was computed with the remaining 30 002 trees using the SUMT command of MrBayes. Bayesian posterior probability (PP) values ≥0.95 were considered to be significant. The alignments and respective phylogenetic trees were deposited in TreeBASE, study number S25967.

Table 2.

Sequenced specimens used in this study, with GenBank accession numbers for 5.8S, 28S, 18S, RPB1, RPB2 and EF-1α regions. Numbers in parentheses following the species names indicate multiple collections of a species. The GenBank accessions of sequences generated in this study are in bold. Asterisks indicate sequences obtained from genome data through the JGI portal (https://jgi.doe.gov/). Abbreviations of datasets are: ag = Agaricales, cl = Clavariineae; hy = Hymenochaetales, pl = Pleurotineae.

Original name	Updated name	Voucher specimen	Dataset	GenBank accession numbers
				5.8S	28S	18S	RPB1	RPB2	EF-1α
Agaricus bisporus∗	—	H97	ag	Genome	Genome	Genome	genome	Genome	genome
Alloclavaria purpurea	—	PBM 2731 (CUW)	hy	DQ486690	DQ457657	DQ437679	—	—	—
Anomoporia bombycina	—	CFMR:L-6240	cl	—	GU187564	—	—	—	—
A. kamtschatica	—	GB/M Edman K426	cl	—	DQ144615	—	—	—	—
Anthracophyllum archeri	—	PBM 2201 (WTU)	ag	DQ444308	AY745709	DQ092915	DQ435799	DQ385877	DQ028586
Amanita brunnescens	—	PBM 2429 (CUW)	ag	AY789079	AY631902	AY707096	AY788847	AY780936	AY881021
Aphanobasidium pseudotsugae	—	HHB-822 (CFMR)	ag, pl	GU187509	GU187567	GU187620	GU187695	GU187781	GU187695
Armillaria mellea	—	PBM 2470 (CUW)	ag	AY789081	AY700194	AY787217	AY788849	AY780938	AY881023
Baeospora myosura	—	PBM 2748 (CUW)	ag	DQ484063	DQ457648	DQ435796	DQ435801	DQ470827	GU187762
Basidioradulum radula	—	GEL 2493 (KASSEL)	hy	DQ234537	AY700184	AY771611	—	—	—
Blasiphalia pseudogrisella	—	P. Hoijer 4393 (H7031951)/ IO.14.231 (S)	hy	MF319048	MF318899	MF318990	—	MT24239	—
Bolbitius vitellinus	—	MTS 5020 (WTU)	ag	DQ200920	AY691807	AY705955	DQ435802	DQ385878	DQ408148
Camarophyllopsis schulzeri	—	S. Jacobsson 3453 (H)	cl	—	AM946415	—	—	—	—
Cantharellopsis prescotii	—	I. Kytovuori 08-0808/ H6059300	hy	MF319050	MF318901	MF318992	—	MF288855	—
Cantharocybe gruberi	—	PBM 510 (WTU)	ag, pl	DQ200927	DQ234540	DQ234546	DQ435808	DQ385879	DQ059045
Ceratellopsis acuminatea	—	CBS 146691	ag, cl	MT232347	MT232298	MT232493	MT24236	MT24230	MT242352
C. aculeatea	—	ARAN-Fungi 13729	cl	—	MT232300	—	—	—	—
C. aff. acuminatea	—	ARAN-Fungi 11746	cl	MT232348	MT232299	—	—	—	—
C. sagittiformis(1)	Bryopistillaria sagittiformis	IO.15.41 (S)	hy	—	MT232301	—	—	MT24231	—
C. sagittiformis(2)	B. sagittiformis	IO.15.85 (S)	hy	—	MT232302	—	—	MT24232	—
C. sagittiformis(3)	B. sagittiformis	IO.14.164 (S)	hy	MT232349	MT232303	—	—	MT24233	—
Cheimonophyllum candidissimum	—	PBM 2411 (WTU)	ag	DQ486687	DQ457654	DQ435812	DQ447888	DQ470831	GU187760
Calocera cornea	—	GEL 5359 (KASSEL)	hy	AY789083	AY701526	AY771610	—	AY536286	—
Clavaria acuta(1)	—	RHP55840 (TENN043602)	cl	—	HQ877681	—	—	—	—
C. acuta(2)	—	MTS4577 (WTU)	cl	—	HQ877679	—	—	—	—
C. acuta(3)	—	JFA10440 (WTU)	cl	—	HQ877680	—	—	—	—
C. alboglobospora	—	TENN042295	cl	—	HQ877682	—	—	—	—
C. argillacea	—	TFB10720 (TENN058804)	cl	—	HQ877683	—	—	—	—
C. australiana	—	ADM1311 (TENN051311)	cl	—	HQ877685	—	—	—	—
C. aff. fragilis	—	SAT98-349-01 (WTU)	cl	—	HQ877688	—	—	—	—
C. fumosa	—	GG_151003	cl	—	EF535268	—	—	—	—
C. fuscata	—	RHP55840 (TENN043602)	cl	—	HQ877681	—	—	—	—
C. inaequalis	—	MB 04-016 (WTU)	cl	—	AY745693	—	—	—	—
C. pullei	—	KGN98	cl	—	AY586646	—	—	—	—
C. cf. rubicundula	—	TENN043695	cl	—	HQ877697	—	—	—	—
Clavaria sp.(1)	—	TFB11835 (TENN060720)	cl	—	HQ877692	—	—	—	—
Clavaria sp.(2)	—	JMB10061001 (TENN065665)	cl	—	HQ877684	—	—	—	—
C. stegasauroides	—	PBM3373	cl	—	HQ877698	—	—	—	—
C. zollingeri	—	JMB08040912 (TENN064095)	cl	—	HQ877700	—	—	—	—
Clavicorona taxophila	—	9186	cl	—	AF115333	—	—	—	—
Clavulinopsis amoena	—	PBM3381	cl	—	HQ877702	—	—	—	—
C. corallinorosacea	—	PBM3380	cl	—	HQ877707	—	—	—	—
C. fusiformis	—	MGW672 (TENN064110)	cl	—	HQ877717	—	—	—	—
C. sulcata	—	PBM3379	cl	—	HQ877709	—	—	—	—
Clitocella mundula	—	TJB 7599 (CORT)	ag	DQ494694	AY700182	DQ089017	DQ447937	DQ474128	—
C. candicans	—	WTU	ag	DQ202268	AY645055	AY771609	DQ447891	DQ385881	DQ408149
C. subditopoda	—	WTU	ag	DQ202269	AY691889	AY771608	DQ447892	AY780942	DQ408150
Coltricia perennis	—	P. Salo 11024 (H)	hy	MF319056	MF318907	MF318996	—	MF288856	—
Collybia tuberosa	—	TENN 53540	ag	AY854072	AY639884	AY771606	AY857982	AY787219	AY881025
Conocybe lactea	—	PBM 2411 (WTU)	ag	DQ486693	DQ457660	DQ437683	DQ447893	DQ470834	—
Coprinus comatus	—	ECV 3198 (UC)	ag	AY854066	AY635772	AY665772	AY857983	AY780934	AY881026
Coprinopsis cinerea∗	—	AmutBmut #326	ag	genome	Genome	genome	genome	genome	genome
Coronicium alboglaucum	—	NH4208	pl	AY463400	AY586650	—	—	—	—
Cortinarius iodes	—	WTU	ag	AF389133	AY702013	AY771605	AY857984	AY536285	AY881027
Cotylidia sp.	—	WTU	hy	AY854079	AY629317	AY705958	—	AY883422	—
C. undulatea	—	IO.15.126 (S)	hy	MT232350	MT232304	—	—	MT24234	—
Crepidotus cf. applanatus	—	PBM 717 (WTU)	ag	DQ202273	AY380406	AY705951	AY333303	AY333311	DQ028581
Cristinia sp.	—	FP-100305 (CFMR)	pl	GU187526	GU187585	GU187637	GU187470	GU187793	GU187718
Entoloma prunuloides	—	TJB 4765 (CORT)	ag	DQ206983	AY700180	AY665784	DQ447898	DQ385883	DQ457633
Globulicium hiemale	—	Hjm 19007 (GB)	hy	DQ873595	DQ873595	DQ873594	—	—	—
Gymnopus contrarius	—	PBM 2711 (WTU)	ag	DQ486708	DQ457670	DQ440643	DQ447902	DQ472716	GU187700
Gyroflexus brevibasidiata	—	IO.14.230 (S)	hy	MT232351	MT232305	—	—	MT24235	—
Fibricium rude		GEL 2121 (KASSEL)	hy	—	AY700202	AY654888	—	—	—
Fistulina Antarctica	—	— (AFTOL-ID 1335)	ag	DQ486702	AY293181	AY293131	DQ447899	DQ472713	GU187698
Flammulina velutipes	—	TENN 52002	ag	AY854073	AY639883	AY665781	AY858966	AY786055	AY883423
Hemimycena gracilis	—	PBM 2715 (WTU)	ag	DQ490623	DQ457671	DQ440644	DQ447905	DQ472719	GU187709
Hirticlavula elegans	—	JHP-13.364 (O)	cl	—	KJ939349	—	—	—	—
Hodophilus aff. foetens	—	ECV4175 (TENN065670)	cl	—	HQ877678	—	—	—	—
Hodophilus hymenocephalus(1)	—	WTU	cl	—	DQ457679	—	—	—	—
H. hymenocephalus(2)	—	DJL98_081505	cl	—	EF561628	—	—	—	—
Hohenbuehelia tremula	—	PBM 2301 (WTU)/ DAOM 180808	pl	DQ182504	KU355405	DQ440645	—	KU355434	KU355465
Hydropus cf. scabripes	—	WTU	ag	DQ404389	DQ411536	DQ444855	DQ447908	DQ457634	—
Hygrocybe coccinea	—	PBM 915 (WTU)	ag, cl	DQ490629	DQ457676	DQ444858	DQ447910	DQ472723	GU187705
H. aff. conica	—	CBS 300.56	cl	—	DQ534589	—	—	—	—
Hygrophorus pudorinus	—	PBM 2721 (WTU)	ag	DQ490631	DQ457678	DQ444861	DQ447912	DQ472725	GU187710
Hyphodontia alutaria	—	KHL 11889 (GB)	hy	DQ873603	DQ873603	DQ873602	—	—	—
Hyphodontiella multiseptata	—	Ryberg 021022 (GB)	cl	—	EU118634	—	—	—	—
Inocybe myriadophylla	—	JV 19652F (WTU)	ag	DQ221106	AY700196	AY657016	DQ447916	AY803751	DQ435791
Inonotus griseus	—	Dai 13436	hy	KX674583	KX364823	—	—	KX364919	—
Infundibulicybe gibba	—	JCS 0704B (WTU)	ag	DQ490635	DQ457682	DQ115780	DQ447913	DQ472727	GU187759
Kneiffiella subalutacea	—	KHL 11888 (GB)	hy	DQ873630	DQ873631	DQ873629	—	—	—
Kuehneromyces rostratus	—	PBM 2703 (WTU)	ag	DQ490638	DQ457684	DQ457624	DQ447918	DQ472730	GU187712
Laccaria bicolor∗	—	S238N	ag	genome	genome	genome	genome	genome	genome
Lachnella villosa	—	CBS 609.87	ag	DQ097362	DQ097347	AY705959	—	DQ472732	GU187721
Leifia flabelliradiata	—	KG Nilsson 36270 (GB)	hy	DQ873635	DQ873635	—	—	—	—
Lepista irina	—	PBM 2291 (WTU)	ag	DQ221109	DQ234538	AY705948	DQ447919	DQ385885	DQ028591
Lycoperdon pyriforme	—	DSH 96-054 (WTU)	ag	AY854075	AF287873	AF026619	AY860523	AY218495	AY883426
Macrolepiota dolichaula	—	HKAS	ag	DQ221111	DQ411537	AY771602	DQ447920	DQ385886	DQ435785
Macrotyphula fistulosa(1)	—	IO.14.219 (S)/ IO.15.123 (ARAN-Fungi, S)/ TUB 011469	ag	—	DQ071735	MT232494	DQ068002	MT24236	MT242353
M. fistulosa(2)	—	IO.14.214 (ARAN-Fungi, S)	ag	MT232352	KY224088	MT232495	MT24237	—	MT242354
M. juncea s.l.	—	IO.14.177 (S)	ag	MT232353	MT232306	MT241267	—	MT24237	MT242355
Megacollybia platyphylla	—	TENN 59432	ag	DQ249275	AY702016	AY786053	DQ447923	DQ385887	DQ435786
Mucronella calva(1)	—	JS16142	cl	—	AY586689	—	—	—	—
M. calva(2)	—	GEL4458	cl	—	AJ406588	—	—	—	—
M. aff. calva	—	KHL10317	cl	—	AY586690	—	—	—	—
M. flava	—	IO.16.84 (S)	ag, cl	MT232354	MT232307	MT232496	MT24238	—	MT242356
M. fusiformis	—	DJM 1309	ag, cl	—	DQ284905	—	—	—	—
M. pendula	—	PBM 3437	ag, cl	—	HQ829921	—	—	—	—
Muscinupta laevis	—	V. Haikonen 19745 (H6059292)	hy	MF319066	MF318921	MF319004	—	MF288861	—
Mycetinis alliaceus	—	TENN 55620	ag	AY854076	AY635776	AY787214	AY860526	AY786060	AY883431
Odonticium romellii	—	KHL s. n. (GB)	hy	DQ873639	DQ873639	DQ873638	—	—	—
Onnia scaura∗	—	P53A	hy	genome	Genome	genome	—	genome	—
Oxyporus populinus	—	Dai 12793/ DSH 93-188	hy	KF111019	KF111021	AF026616	—	KT210380	—
Peniophorella praetermissa	—	GEL 2182 (KASSEL)	hy	AY854081	AY700185	AY707094	—	AY787221	—
P. pubera	—	KHL 13154 (GB)	hy	DQ873599	DQ873599	DQ873598	—	—	—
Pluteus romellii	—	ECV 3201 (UC)	ag	AY854065	AY634279	AY657014	AY862187	AY786063	AY883433
Phaeomarasmius proximans	—	PBM 1951 (WTU)	ag	DQ404381	AY752970	AY752970	—	AY333314	DQ028592
Phellinidium ferrugineofuscum∗	—	SpK3Phefer14		genome	genome	genome	—	genome	—
Phellinus tremulae	—	KCTC 6659/ NJB2011-PT2-F	hy	AY189703	KU139202	AY178026	KU139277	—	—
Phyllotopsis nidulans	—	IO.14.196 (S)	ag, pl	—	MT232308	MT232497	MT24239	MT24238	MT242357
Phyllotopsis sp.	—	MB 35 (WTU)	ag, pl	DQ404382	AY684161	AY707090	DQ447933	AY786061	DQ059047
Porotheleum fimbriatum	—	CBS 788.86	ag	DQ490626	DQ457673	DQ444854	DQ447907	DQ472721	—
Pleurocybella porrigens	—	JFA 12544 (WTU)/TUB012154/ UPS F-611822	ag, pl	MT232355	MT232309	GU187660	DQ067994	MT24239	GU187740
Pleurotus eryngii	—	X102	ag, pl	KX977448	—	FJ379286	—	—	—
P. ostreatus	—	TENN 53662		NG_027634	AY645052	AY657015	AY862186	AY786062	AY883432
Plicaturopsis crispa∗	—	FD-325 SS-3	ag, pl	genome	genome	genome	genome	genome	genome
Podoserpula pusio	—	Hlepp-329	ag	—	EF535271	—	—	—	—
Porodaedalea pini	—	No-6170-T	hy	JX110037	JX110081	—	—	JX109951	—
Pseudoclitocybe cyathiformis	—	JFA 12811 (WTU)/GLM 46020 (GB)	ag	GU187553	EF551313	GU187659	DQ067939	GU187815	GU187742
Pterulicium echo(1)	—	DJM 302S58 (MINN)	ag, pl	DQ494693	AY458123	DQ092911	—	GU187805	GU187743
P. echo(2)	cf. Pterula	ZRL20151311	pl	LT716065	KY418881	KY418947	KY418979	KY419026	KY419076
P. gracile∗(1)	—	CBS 309.79	ag, pl	genome	genome	genome	genome	genome	genome
P. gracile(2)	—	IO.14.142 (S)	pl	MT232356	MT232310	MT232498	—	—	MT242358
Radulomyces confluens∗	—	OMC1631	ag, pl	genome	genome	genome	genome	genome	genome
R. molaris	—	ARAN-Fungi 2003	ag, pl	—	MT232311	MT232499	MT24230	MT24230	MT242359
Ramariopsis biformis	—	JMB10061006 (TENN065660)	cl	—	HQ877712	—	—	—	—
R. crocea	—	JMB10071001 (TENN065661)	cl	—	HQ877715	—	—	—	—
R. aff. kunzei	—	Marr5064 (WTU)	cl	—	HQ877719	—	—	—	—
R. pseudosubtilis	—	RHP27722 (TENN027722)	cl	—	HQ877723	—	—	—	—
R. tenuiramosa	—	GG_061104	cl	—	EF535269	—	—	—	—
Repetobasidium conicum	—	KHL 12338 (GB)	hy	DQ873647	DQ873647	DQ873646	—	—	—
R. mirificum	—	FP-133558-sp	hy	—	AY293208	AY293155	—	—	—
Resinicium bicolor	—	GEL 2071 (KASSEL)	hy	DQ218310	AY700183	—	—	DQ457635	—
Rickenella fibula	—	PBM 2503 (WTU)	hy	DQ241782	AY700195	AY771599	—	DQ408115	—
Rhodocollybia maculate	—	WTU	ag	DQ404383	AY639880	AY752966	DQ447936	AY787220	DQ061279
Sarcomyxa serotina	—	WTU/ DSH 93-218	ag, pl	DQ494695	AY691887	AF026590	DQ447938	DQ859892	GU187754
Schizophyllum radiatum	—	FH	ag	AY571060	AY571023	AY705952	DQ447939	DQ484052	—
Schizopora radula	—	Dai 12631	hy	KT203307	KT203328	—	—	KT210382	—
Sclerotium complanatum	Macrotyphula phacorrhiza	Microf. Exs. No. 49 (UPS)	pl	—	MT234400	—	—	—	—
Sistotrema confluens	—	FCUG 298	hy	DQ267125	AY647214	AY757260	—	DQ381837	—
Stephanospora caroticolor	—	TUB019072/ IOC 137-97/ R44008	ag, pl	KM086827	AF518652	AF518591	KF211335	—	GU187747
Trichaptum abietinum∗	—	R44008	hy	genome	genome	genome	—	genome	—
Tubulicrinis globisporus	—	KHL 12133 (GB)	hy	DQ873655	DQ873655	DQ873654	—	—	—
T. inornatus	—	KHL 11763 (GB)	hy	DQ873659	DQ873659	DQ873658	—	—	—
Tygervalleyomyces podocarpi	Typhula podocarpi	CPC 29979		NR_156661	NG_059851	—	—	—	—
Typhula capitata	—	IO.15.122 (S, UPS)/ CBS 143727	ag, pl	MT232357	MT232312	MT232500	MT24231	MT24231	MT242360
T. crassipes	—	IO.14.83 (S, UPS)	ag, pl	MT232358	KY224094	—	—	MT24232	MT242361
T. erythropus	—	IO.14.123 (S, UPS)/ CBS 143797	ag, pl	MT232359	KY224096	MT232501	MT24232	MT24233	MT242362
T. gyrans	—	IO.14.103 (S)/ CBS 143796	ag, pl	MT232360	KY224097	MT232502	MT24233	MT24234	MT242363
T. micans	—	IO.14.165 (S)	ag, pl	MT232361	KY224102	MT232503	MT24234	MT24235	MT242364
T. incarnata	—	IO. 14. 92 (S)/ CBS 143742/ CBS 350.79	ag, pl	MT232362	MT232313	MT232504	MT24235	MT24236	MT242365
T. phacorrhiza(1)	Macrotyphula phacorrhiza	IO.14.200 (S)	ag, pl	MT232363	MT232314	MT232505	—	MT24237	MT242366
T. phacorrhiza(2)	M. phacorrhiza	IO.14.167 (S)	ag, pl	MT232364	MT232315	MT232506	MT24236	MT24238	MT242367
T. phacorrhiza(3)	M. juncea s.l.	DSH 96-059	pl	—	AF393079	AF026630	—	AY218525	—
T. phacorrhiza(4)	M. phacorrhiza	ARAN-Fungi 7446	pl	—	MT232316	—	—	—	MT242368
T. sclerotioides	—	IO.14.22 (S)	ag, pl	MT232365	MT232317	MT232507	MT24237	MT24239	MT242369
T. subhyalina	—	IO.15.06 (S)/ CBS 143735	ag, pl	MT232366	MT232318	MT232508	—	MT24230	MT242370
T. uncialis	—	IO.14.74 (S)	ag, pl	MT232367	MT232319	MT232509	MT24238	MT24231	MT242371
Uncultured Basidiomycota(5)	Ceratellopsis sp.	Soil sample	cl	DQ341741	DQ341741	—	—	—	—
Uncultured Basidiomycota(1)	Ceratellopsis sp.	Soil sample	cl	HQ433218	HQ433218	—	—	—	—
Uncultured Basidiomycota(2)	Ceratellopsis sp.	Soil sample	cl	GQ159941	GQ159941	—	—	—	—
Uncultured Basidiomycota(3)	Ceratellopsis sp.	Soil sample	cl	EU691875	EU691875	—	—	—	—
Uncultured Basidiomycota(4)	Ceratellopsis sp.	Soil sample	cl	EU861817	EU861817	—	—	—	—
Uncultured Basidiomycota(5)	Ceratellopsis sp.	Soil sample	cl	DQ341741	DQ341741	—	—	—	—
Uncultured Basidiomycota(6)	Ceratellopsis sp.	Soil sample	cl	EF434117	EF434117	—	—	—	—
Uncultured Basidiomycota(7)	Ceratellopsis sp.	Soil sample	cl	GQ159939	GQ159939	—	—	—	—
Xerula radicata	—	TENN 59235	ag	DQ241780	AY645051	AY654884	DQ447946	AY786067	DQ029194
Xylodon rimosissimus	—	CBS 105.045/ Ryberg 021031 (GB)	hy	DQ873627	DQ873628	DQ873626	—	LN714662	—

Results

Origins of typhuloid fungi within Agaricales and Pleurotineae

A total of 118 (21 5.8S, 23 28S, 18 18S, 13 RPB1, 23 RPB2, 20 EF-1α) sequences were generated for this study (Table 2). The Agaricales matrix comprised 81 taxa and contained 6 292 unambiguously aligned nucleotide positions (161 nu5.8S, 1 480 nu28S, 1 745 nu18S, 861 RPB1, 1 056 RPB2 and 989 EF-1α), with all genes available for 86.4 % of taxa. The Pleurotineae matrix had 39 taxa and contained 6 215 unambiguously aligned nucleotide positions (159 nu5.8S, 1 418 nu28S, 1 732 nu18S, 863 RPB1, 1 056 RPB2 and 987 EF-1α), with all genes available for 72.2 % of taxa. The Bayesian analysis of the Agaricales and Pleurotineae datasets reached average standard deviations of split frequencies > 0.01 after 12 195 000 and 425 000 generations, respectively. The Bayesian majority rule consensus tree of the Agaricales was fully resolved and many deeper branches received high support by Bayesian PP (Fig. 2). The majority of these branches were, however, not supported by ML-BP (< 70 %). Typhuloid fungi do not form a monophyletic group. Specimens with skeletal hyphae nest in Pleurotineae (Pterulicium gracile) and in Clavariineae (C. acuminata). Sequences of the specimen of P. gracile collected by us (IO.14.142) were identical to those obtained from the available genome of P. gracile (CBS 309.79) (Fig. 3), employed also by Leal-Dutra et al. (2020). Clavariineae forms a strongly supported clade (PP 1, ML-BP 86) that is resolved as an early diverging lineage within Agaricales (PP 1). Ceratellopsis acuminata forms a highly supported clade with Ramariopsis kunzei (PP 1, ML-BP 100). The remaining Agaricales form a strongly supported monophyletic group (PP 1), within which Ampulloclitocybe clavipes, Cantharocybe gruberi, Hygrocybe coccinea, Hygrophorus pudorinus and Pseudoarmillariella ectypoides, corresponding to the Hygrophoraceae, constitute a strongly supported lineage in the Bayesian analysis (PP 0.98), as a sister group to the rest of the Agaricales (PP 1). The suborders Agaricineae (PP 0.96), the Tricholomatineae (PP 1), the Marasmiineae (PP 0.99) and the Pluteineae (PP 0.95) also received high support in the Bayesian analysis. Xeromphalina campanella, previously assigned to the hygrophoroid clade, is supported as an early diverging sister lineage to the Marasmiineae (PP 0.99). Species of Typhula and Macrotyphula form a well-supported clade together with other pleurotoid, clavarioid, corticioid and gasteroid species (PP 0.95) that is referred to the Pleurotineae. The Agaricales (ag) and Pleurotineae (pl) phylogenies (Fig. 2, Fig. 3) show similar supported nodes in the Pleurotineae, except that the Pleurotaceae formed a sister group to the rest of the Pleurotineae in both Bayesian and ML analyses of the Pleurotineae matrix (PP 1, ML-BP 99). In all analyses T. phacorrhiza is nested within a monophyletic Macrotyphula (ag PP 1, ML-BP 100; pl PP 1, ML-BP 100). A specimen identified as Sclerotium complanatum is nested within a clade of three T. phacorrhiza collections in the analyses of the Pleurotineae matrix. The Macrotyphula clade is encompassed in a larger supported clade together with Phyllotopsis and Pleurocybella porrigens (pl PP 1). Stephanospora caroticolor, Cristinia rhenana, Pterulaceae and Radulomycetaceae (Aphanobasidium, Radulomyces) form a strongly supported clade (pl PP 1, ML-BP 73) sister to the Macrotyphula clade, Phyllotopsis and Pleurocybella porrigens. All Typhula species but its type T. phacorrhiza, form a distinct separate lineage (pl PP 1, ML-BP 100). It includes the types of Cnazonaria, Dacryopsella, Gliocoryne, Phacorhiza, Pistillaria, Pistillina, Scleromitra, Sphaerula and Tygervalleyomyces. Typhula is a sistergroup to the clade formed by Macrotyphula, Phyllotopsis, Pleurocybella porrigens, Pterulaceae and Stephanosporaceae in the Pleurotineae phylogeny (Fig. 3), albeit without support (pl PP 0.94). Pleurotus and Hohenbuehelia tremula are supported as a sistergroup to the rest of the Pleurotineae in the Pleurotineae phylogeny (Fig. 3, PP 1, ML-BP 99).

Fig. 2.

Bayesian inference 50 % majority rule consensus phylogram of the Agaricales from 5.8S-18S-28S-RPB1-RPB2-EF-1α sequence data, with the placement of typhuloid fungi (in blue font). Bayesian posterior probabilities (PP) and Maximum Likelihood bootstrap values (ML-BP) are shown on branches, ordered as PP/ML-BP. Thickened branches received support at least in one analysis (ML-BP ≥ 70 % and/or PP ≥ 95 %). Suborder names recognised within the Agaricomycetes are indicated on the right side.

Fig. 3.

Bayesian inference 50 % majority rule consensus phylogram of the Pleurotineae from 5.8S-18S-28S-RPB1-RPB2-EF-1α sequence data. Bayesian posterior probabilities (PP) and Maximum Likelihood bootstrap values (ML-BP) are shown on branches, ordered as PP/ML-BP. Thickened branches received support at least in one of the analyses (ML-BP ≥ 70 % and/or PP ≥ 95 %). Family names recognised within the Pleurotineae are marked with colour boxes. Basidioma types are indicated with different colours for ingroup taxa.

The Clavariaceae phylogeny

The Clavariaceae matrix comprised 53 taxa and contained 1 505 unambiguously aligned nucleotide positions (28S rDNA). Bayesian and ML analyses produced very similar topologies (Fig. 4). Species of Mucronella form a highly supported sister group to the rest of the Clavariaceae (PP 1, ML-BP 100). Clavaria, Camarophyllopsis, Hodophilus and Hirticlavula elegans form a highly supported monophyletic group (PP 1, ML-BP 84), characterised by lacking clamp connections on context hyphae in all species but Clavicorona taxophila. Three species of Ceratellopsis form a distinct clade with several environmental sequences (uncultured Basidiomycota in GenBank). The relationships of the Ceratellopsis clade to the other genera with clamp connections, Ramariopsis and Clavulinopsis, are not resolved with support.

Fig. 4.

Bayesian inference 50 % majority rule consensus phylogram of the Clavariineae from 28S sequence data. Bayesian posterior probabilities (PP) and Maximum Likelihood bootstrap values (ML-BP) are shown on branches, ordered as PP/ML-BP. Thickened branches received support at least in one analysis (ML-BP ≥ 70 % and/or PP ≥ 95 %). Basidioma types are indicated with different colours for ingroup taxa.

The Hymenochaetales phylogeny

The Hymenochaetales matrix contained 37 taxa and 4 239 unambiguously aligned characters. The majority rule consensus tree of the Bayesian analysis is provided in Fig. 5. The Hymenochaetales is recovered as monophyletic with high support in the Bayesian analysis (PP 1, ML-BP 62). It comprises two larger clades: a) a clade containing Coltricia, Kneiffiella, Xylodon and Hymenochaetaceae, corresponding to clades C–F in Larsson et al. (2006), along with two species of Repetobasidium (PP 0.91, ML-BP 26); and b) a clade corresponding to the Rickenella clade (clade B in Larsson et al. 2006) (PP 1, ML-BP 57). Within the Rickenella clade, the three Ceratellopsis sagittiformis specimens are encompassed in a well-supported clade (PP 1, ML-BP 65) with species of agaricoid (Blasiphalia, Cantharellopsis, Gyroflexus, Rickenella), clavarioid (Alloclavaria), corticioid (Globulicium, Hyphodontia, Peniophorella, Resinicium), cyphelloid (Muscinupta) and thelephoroid (Cotylidia) basidiomata. The position of Hyphodontia alutaria and Resinicium bicolor is in conflict; both species form a supported monophyletic group with Rickenella fibula and C. sagittiformis in the Bayesian analysis (PP 99), as opposed to a monophyletic group with Cotylidia spp. in the ML analysis (ML-BP 75).

Fig. 5.

Bayesian inference 50 % majority rule consensus phylogram of the hymenochaetoid clade from 5.8S-18S-28S-RPB2 sequence data. Bayesian posterior probabilities (PP) and Maximum Likelihood bootstrap values (ML-BP) are shown on branches, ordered as PP/ML-BP. Thickened branches received support at least in one analysis (ML-BP ≥ 70 % and/or PP ≥ 95 %). Basidioma types are indicated with different colours for ingroup taxa.

Taxonomy

Clavariineae Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, subord. nov. MycoBank MB831365.



Basidiomata clavarioid, more rarely agaricoid with waxy decurrent gills, or corticioid. Hyphal system monomitic, or more rarely dimitic. Basidiospores hyaline, usually thin-walled, smooth or ornamented, usually with multiguttulate contents, sometimes with amyloid or dextrinoid reactions, usually with a cubic apiculus. Basidia claviform, with up to 4 sterigmata, chiastic, sometimes characteristically long (< 50 μm) or short (> 20 μm), occasionally sometimes with a loop-like basal clamp (Clavaria subgen. Holocoryne). Cystidia usually absent. Pileipellis either a hymeniderm or a trichoderm with rounded terminal elements in genera with agaricoid basidiomata. Basal tomentum composed of narrow, usually < 2 μm broad thick-walled hyphae in clavarioid genera (Ceratellopsis, Clavaria, Clavulinopsis, Ramariopsis), possibly also in other stipitate genera. Clamp connections present or absent, sometimes restricted to basidia. Saprotrophic on dead wood, herbaceous plants or leaves, or biotrophic with grasses and bryophytes. Presence of EF-1α intron 21 (numbering according to Matheny et al. 2007) in some genera (absent in Ceratellopsis).



Type family: Clavariaceae Chevall.



Notes: This suborder contains a single family. Similar isotopic ratios to those found in the Hygrophoraceae suggest that at least non-lignicolous members of Clavariaceae have some kind of biotrophic association with plants (Birkebak et al. 2013), whereas genera occurring on dead plant remnants are probably saprotrophic (Ceratellopsis, Mucronella, Hirticlavula). Very narrow and slightly thick-walled hyphae in the basal tomentum and mycelium are characteristic for many species of Clavariaceae, including species in Clavaria, Clavulinopsis, Ramariopsis (Olariaga 2009) and Ceratellopsis (Fig. 6) and it might be a synapomorphic character of the Clavariineae. The presence of EF-1α intron 21, absent in the rest of the Agaricales (Matheny et al. 2007) seems so far unique to some Clavariaceae (Clavaria, Clavulinopsis, Camarophyllopsis).



Fig. 6.

Ceratellopsis acuminata (epitype, Huhtinen 15/07, S). A–C. Dried basidiomata. D. Basidioma observed using a light microscope. E. Close-up of basidioma apex. F. Basidiospores. G. Basidia. H. Medullar hyphae resembling skeletal hyphae. I. One-year-old culture in MEA, kept at 5 °C (culture ex-epitype, CBS 146691). J. Hyphae from cultured mycelium (culture ex-epitype, CBS 146691). Mounting media were Melzer's reagent (D), Congo Red in ammonia (E–H) and water (I). Scale bars: D = 100 μm, E–H = 10 μm; I = 10mm. Photographs I. Olariaga.

Clavariaceae Chevall., Fl. Gen. Env. Paris 1: 102. 1826. [“Clavariae”; “ordre”; considered family according to Art. 18.2].



Type genus: Clavaria Vaill. ex L. : Fr.



Genera: Camarophyllopsis, Ceratellopsis, Clavaria, Clavulinopsis, Hirticlavula, Hodophilus, Hyphodontiella, Mucronella, Ramariopsis.



Ceratellopsis Konrad & Maubl., Icon. Select. Fung. 6: 502. 1937.

Basionym: Ceratella Pat., Hymenomyc. Eur.: 137. 1887. [nom. illeg. Art. 53.1, later homonym of Ceratella Hook f. 1844].



Presumed saprobic on bark, dead wood or culms. Basidiomata gregarious, clavarioid, 0.2–1(–2) mm high, lanceolate with a sterile pointed apex, white. Stipe usually present, short, glabrous or pubescent. Hyphal system monomitic or dimitic. Basidiospores without iodine reactions. Basidia claviform, short, 10–16 μm long. Generative hyphae present in the medulla, unidirectional, cylindrical, septate, thick-walled, 1–2.5 μm broad, sometimes dextrinoid. Skeletal hyphae present in the medulla of C. acuminata and further undescribed species known by us. Clamp connections scattered.



Type: Ceratellopsis acuminata (Fuckel) Corner, typ. cons. prop.



Notes: The background of the name Ceratellopsis requires, however, further clarification as its type has been a matter of controversy. According to our nomenclatural study, Ceratellopsis is a validly published replacement name based on Ceratella Pat. and typified by Pistillaria queletii. The final epithet Ceratella was first employed by Quélet (1886) for an unranked infrageneric name. Later, although Patouillard (1887) referred to Ceratella as “CERATELLA (Quél.)” he did not have in mind Clavaria [unranked] Ceratella as the basionym of a new combination. As explained in the introduction of the Hyménomycètes (Patouillard 1887: VII), authors of generic names were cited between round brackets only when Patouillard's circumscriptions were absolutely different from the original ones. Therefore, we consider Ceratella as the name of a new taxon to be cited as “Ceratella Pat.” (J. McNeill, pers. comm.) in agreement with Donk (1954) and the ING (Farr & Zijlstra 2020). Nevertheless, Ceratella Pat. (1887) is illegitimate as a later homonym of Ceratella Hook f. (1846). When Ceratellopsis was introduced, Konrad & Maublanc (1937) referred to it as a new name for “Ceratella (Quélet p.p.), Patouillard (1887)” and proposed Ceratellopsis queletii as the type, without providing a Latin description. Since Ceratellopsis was a replacement name for Ceratella Pat., and not a new taxon, Ceratellopsis is a validly published generic name even though it lacked a Latin description and was published later than 1935 (Art. 39.1), because such is not required for a replacement name. The type proposed for Ceratellopsis by Konrad & Maublanc is also in order, since Ceratella queletii was one of the three species listed under Ceratella Pat. (1887). A relevant fact that might have affected the typification of Ceratellopsis is whether the combination Ceratella queletii was validly published when Patouillard erected Ceratella Pat. Patouillard (1887) listed C. queletii as “C. Queletii” without explicitly citing its basionym Pistillaria queletii. However, we interpret that Patouillard (1887: VI) gave an indirect reference to the basionym that fulfils conditions for valid publication of C. queletii (Art. 41.3 and 38.14) by explicitly stating that Tabulae Analyticae Fungorum, the place of publication of Pistillaria queletii, basionym C. queletii, was one of the main works on which he based his Hyménomycètes (Art. 41.4, Ex. 9), and because Patouillard himself was author of the basionym.

For details on our choice to suggest C. acuminata as the conserved type for Ceratellopsis see notes under Pterulicium and the Discussion.



Ceratellopsis acuminata (Fuckel) Corner, Ann. Bot. Mem. 1: 202. 1950. Fig. 6.

Basionym: Pistillaria acuminata Fuckel, Fungi Rhen. Exs. (suppl.) 4: no 1888. 1867.

Synonym: Ceratella acuminata (Fuckel) Pat., Essai Tax. Hyménomyc.: 49. 1900.



Basidiomata gregarious, 0.2–0.4 mm high, simple, with a short stipe and a sterile apex. Fertile part cylindrical to oblong, sharply delimited from the stipe and the apex, white, 0.1–0.3 × 0.02–0.04 mm. Stipe short, cylindrical, glabrous, hyaline white, 0.04–0.12 × 0.01–0.02 mm. Apex pointed, acute, hyaline white, 0.04–0.1 mm long. Basidiospores ellipsoid to pip-shaped, sometimes in tetrads, hyaline, without iodine reactions, (3–)4–6 × (1.5–)2–3 μm. Basidia claviform, 2–4-spored, 10–16 × 3.5–4.5 μm, clamped. Generative hyphae cylindrical, hyaline, thin-walled, clampless, sometimes with scarce septa at the stipe base, 1–2.2 μm broad. Skeletal hyphae present in the medulla, cylindrical, refractive, slightly dextrinoid, 1.2–2.8 μm broad. Colonies on MEA 30–40 mm diam after 1 yr at 5 °C, superficial, effuse, convex, tomentose, hard-textured, with erect white tufts and strong smell reminiscent of Scleroderma. Reverse white. Margin regular and distinct. Vegetative hyphae cylindrical, closely septate, very slightly thick-walled, hyaline, 2.5−4 μm broad, with scattered clamp connections. Asexual morph not observed in culture.



Typus: Germany, Nassau, Johannisberger Schlosswald, ad pini sylv. folia putrida falae humus, Fuckel, Fungi Rhen. Exs. no 1888 (S-F128455 !, lectotype of Pistillaria acuminata designated here, MycoBank MBT387677). Isolectotypes: S-F128454 (!), S-F267533 (!), FH00608504 (!), K(M) 159801, M. Sweden, Härjedalen, Tänndalen, Hamrafjället Nature Protection Area, on dead leaves of Dryas octopetala, 4 Aug. 2015, S. Huhtinen 15/07 (S, epitype of Pistillaria acuminata designated here, MycoBank MBT389356). Culture ex-epitype: CBS 146691.



Known distribution: Denmark, Finland, France, Germany, Norway, Spain and Sweden.



Additional materials examined: Denmark, Sjælland, Bognæs skov, on leaves of Leymus on exposed beach, 26 Oct. 2019, T. Læssøe, DMS-10058526 (C). Finland, Perä-Pohjanmaa, Rovaniemi, Lovevaara Nature Protection area, brookside herb-rich forest, on leaf litter under alders, 7 Sep. 2012, S. Huhtinen 12/15 (TUR 197690). France, Val-d'Oise, Montmorency, ad cortices, 1889, Boudier herbarium (PC). Norway, Finnmark, Nord Varanger, Varanger Peninsula, Fosefjellet (ca. 3 km NW of Vadsö), on hare dung (Lepus tumidus) in moist chamber, 27 Jul. 1966, N. Lundqvist 4965g (UPS F-152857). Sweden, Gästrikland, Gävle, Lövudden, Salix viminali, folia dejecta, 25 Jun. 1953, J.A. Nannfeldt 12806 (UPS F-152650, as Ceratellopsis sp.); Lycksele Lappmark, Saxnäs, Satsfjället, on dead fern stems, 28 Jul. 2010, K. Hansen, K. Gillen & I. Olariaga, IO.10.01 (S); Västergötland, Håkantorp, Äspås hållplats, on Quercus robur leaves, 2 Oct. 1955, S. Kilander (UPS F-152830).



Notes: Ceratellopsis acuminata differs from C. aculeata in having skeletal hyphae in the basidioma core. Another collection identified as C. aff. acuminata by us (ARAN-Fungi 11746) possessed also skeletal hyphae, but had longer and shorter basidiomata and nested in a different clade than the epitype of C. acuminata (Fig. 4). This substantiates the idea that an additional species of Ceratellopsis exists and when more specimens become available the species limits should be studied further.

Corner (1950: 203) mentioned a type collection of Pistillaria acuminata (that Donk had examined in ms) without providing a collection number or a herbarium. Since we believe that Corner's type indication did not fulfil requirements for achieving a valid typification (Art. 7.11), we propose here a lectotypification of C. acuminata. The four syntypes examined are very meagre. Therefore, we select as epitype a recent collection from which a living culture and several gene regions have been obtained. We found C. acuminata to have a very broad host range and distribution, and feel justified in selecting Swedish material collected on Dryas leaves as epitype.



Ceratellopsis aculeata (Pat.) Corner, Ann. Bot. Mem. 1: 200. 1950.

Basionym: Pistillaria aculeata Pat., Tab. anal. Fung. 1: 26. 1883.

Synonyms: Ceratella aculeata Pat., Essai Tax. Hyménomyc.: 49. 1900.

(?) Pistillaria mucedinea Boud., Bull. Soc. bot. Fr. 24: 308. 1878. [1877].

(?) Ceratellopsis mucedinea (Boud.) Corner, Ann. Bot. Mem. 1: 204. 1950.



Typus: No type specimen in the Patouillard herbarium (FH, PC). Lectotype of Pistillaria aculeata designated here: Patouillard, Tab. Anal. Fung. 1: fig. 58. 1883. MycoBank MBT387467.



Specimens examined: Denmark, Lolland, Maribo Søndersø, on stems of Cladium mariscus, 9 Oct. 2000, T. Læssøe, DMS-376001 (C). Spain, Aragón, Huesca, on Pinus bark, 26 Feb. 2017, R. Blasco, ARAN-Fungi 13729; Basque Country, Gipuzkoa, Larraul, Usarrobi erreka, 9 Jun. 2012, I. Olariaga, ARAN-Fungi A3064020. Sweden, Öland, Norra Mosse, on damp, dead parts of Cladium, 2 Jul. 1988, S. Elborne, C-F-94548. UK, England, Wicken fen, on Cladium mariscus, 12 Aug. 1926, E.J.H. Corner (PC).



Notes: Medulla hyphae in Ceratellopsis aculeata are thick-walled and have scarce septa, as noted by Corner (1950). Originally described as occurring on fallen leaves, C. aculeata has been considered to typically occur on dead leaves of Cladium mariscus (Corner, 1950, Hansen and Knudsen, 1997). Specimens collected on bark or dead wood share a similar basidioma configuration, hyphae and spores.

As Corner (1950) suggested Pistillaria mucedinea is very close to C. aculeata. The small size of basidiomata (0.5–0.75 mm) and the 4-spored basidia described in the protologue support this view. Furthermore, our study of an authentic specimen kept at PC, collected on bark as described in the protologue, has scarcely septate thick-walled hyphae as observed in the material on Cladium mariscus. We agree with Corner (1950) and even suggest P. mucedinea might be conspecific with C. aculeata and list it as a possible earlier synonym. However, a better insight on species limits in Ceratellopsis needs to be acquired to further test this.



Names formerly placed in Ceratellopsis and imperfectly known, excluded here or illegitimate 



Ceratellopsis aciculata (Durieu & Lév. ex Sacc.) Corner, Ann. Bot. Mem. 1: 200. 1950.

Basionym: Pistillaria aciculata Durieu & Lév. ex Sacc., Syll. Fung. 6: 759. 1887.



Typus: Lectotype designated here: Bory de Saint-Vincent & Durieu de Maisonneuve, Expl. Sci. Algérie 1(5): tab. 32, fig. 4. 1846. MycoBank MBT387461.



Notes: Pistillaria aciculata, published as a nomen nudum (Bory de Saint-Vincent & Durieu de Maisonneuve 1846), was invalid until Saccardo provided a description. The illustration provided by Bory de Saint-Vincent & Durieu de Maisonneuve (1846) shows brown, pointed acute structures that do not look like a fertile fungus but rather incipient basidiomata of a marasmioid fungus. This figure is, to our knowledge, the only original element and it is accordingly proposed as lectotype.



Ceratellopsis asphodeli (Pat.) Corner, Ann. Bot. Mem. 1: 203. 1950.

Basionym: Ceratella microscopica var. asphodeli Pat., Cat. Pl. Cell. Tunisie: 66. 1897.



Typus: No type specimen in the Patouillard herbarium (FH, PC). No original illustration.



Notes: The 2-spored basidia and the presence of cystidia described in Patouillard (1897) suggest that C. asphodeli is a synonym of Pterulicium gracile. The pink tones can be present in P. gracile (Olariaga 2009).



Ceratellopsis biformis Khurana in Berthier, Bull. Soc. Linn. Lyon. 45: 190. 1976 [nom. illeg., Art. 39, 40].



Notes: The description provided by Berthier (1976) based on Corner's notes of a fungus on Quercus leaves from India suggests that C. biformis may belong to Ceratellopsis as conceived here due to its narrow, 1.5–2 μm broad, medulla hyphae. Nevertheless, C. biformis was never validly published since neither a Latin diagnosis nor a type specimen were provided for it.



Ceratellopsis brondaei (Quél.) Corner, Ann. Bot. Mem. 1: 203. 1950.

Basionym: Clavaria brondaei Quél., Revue mycol. (Toulouse) 14(54): 65. 1892.

Typus: No type specimen in PC and TL.



Notes: Quélet (1892) described C. brondaei apparently based only on the Brondeau plate no. 165 (“Alb. 165”). The illustration provided in the protologue (plate 126, fig. 3), probably a reproduction of plate no. 165, shows a small white clavarioid fungus, said to grow in forest on soil among tiny mosses. The description, except the ecology, tallies with a species of Ceratellopsis as treated here, but in the absence of microscopic information and a type specimen, a reliable interpretation cannot be provided, as Corner (1950) stated.



Ceratellopsis caespitulosa (Sacc.) Corner, Ann. Bot. Mem. 1: 203. 1950.

Basionym: Pistillaria caespitulosa Sacc., Atti del Congr. bot. di Palermo. 1902.



Typus: [from Saccardo, Syll. Fung. 17: 202. 1905]: France, Côte d’Or, in cortice emortuo Loniceræ periclymeni [Lonicera periclymenum], PAD.



Notes: The denticulate “basidia” and the 1-septate biguttulate spores suggest that C. caespitulosa is an asexual morph fungus, probably conspecific with Isaria friesii (Leotiomycetes, Ascomycota).



Ceratellopsis carestiae (Ces.) Corner, Ann. Bot. Mem. 1: 203. 1950.

Basionym: Pistillaria carestiae Ces. in Bres. & Sacc., Malpighia 11: 255. 1897.



Typus: Italy, Piemonte, Alagna Valsesia, sur ramis secchiSyringa vulgaris, 13 Oct. 1857, Ab. Carestia no 27 (S-F15983 !, ex Bresadola herbarium; lectotype designated here, MycoBank MBT387464).



Notes: The material constitutes an asexual fungal state growing on bark, very probably conspecific with Isaria friesii. The spore content, described as divided in two (“plasma bipartito”) is due, in fact, to the 1-septate spores, as in C. caespitulosa (see above).



Ceratellopsis corneri Berthier, Bull. mens. Soc. linn. Lyon 43: 188. 1974.



Typus: France, Lyon, Soucieu-en-Jarrest, sur l´ecorce pourrissante d'un arbre abattu (Gymnosperme?), Bussy, 11 Apr. 1970 (holotype G).



Notes: Due to the 4–6 μm broad medulla hyphae and the amyloid spores, C. corneri does not conform to Ceratellopsis. We consider it that C. corneri should be examined and compared to Mucronella instead.



Ceratellopsis dryopteridis (S. Imai) Corner, Ann. Bot. Mem. 1: 203. 1950.

Basionym: Pistillaria dryopteridis S. Imai, Sapporo Trans. Sapporo nat. Hist. Soc. 13(4): 386. 1934.



Typus: Japan, Ishikari province, Nov. probably at SAPA.



Notes: The filiform 1–5 mm long basidiomata and 9–12.5 μm long spores suggest that C. dryopteridis should not be excluded from Ceratellopsis. The spores of C. dryopteridis are asperulate and therefore a relationship with Pterula is suggested here, but the type specimen, if it exists, should be examined to confirm this.



Ceratellopsis equiseticola (Boud.) Corner, Ann. Bot. Mem. 1: 204. 1950.

Basionym: Pistillaria equiseticola Boud., Bull. Trimestr. Soc. Mycol. France 33(1): 13. 1917.



Typus: France, Saône-et-Loire, Clovey (?), ad caules Equiseti limosi [Equisetum fluviatile], May 1915, Boudier herbarium (PC !, as P. equisetina; lectotype designated here, MycoBank MBT387465).



Notes: As earlier suggested by Berthier (1976), we conclude that C. equiseticola is a synonym of P. gracile after examining type material.



Ceratellopsis graminicola (Bourdot & Galzin) Corner, Ann. Bot. Mem. 1: 204. 1950.

Basionym: Pistillaria graminicola Bourdot & Galzin, Hymenomyc. France: 139. 1928.



Typus: No type specimen in the Bourdot & Galzin herbarium (PC). No original illustration.



Notes: The 12–18 μm long, 2–4-spored basidia, small spores (6–7 × 4 μm) and narrow, 1.5–2.5 μm broad hyphae given in the original description would indicate that C. graminicola should be retained in Ceratellopsis, rather than being conspecific with P. gracile. It might be conspecific with C. aculeata or C. acuminata, but details on its hyphal structure are necessary to provide a solid interpretation.



Ceratellopsis helenae (Pat.) Corner, Ann. Bot. Mem. 1: 204. 1950.

Basionym: Pistillaria helenae Pat., Tab. Anal. Fung. 1: 26. 1883.



Typus: No type specimen in the Patouillard herbarium (FH, PC). Lectotype designated here: Patouillard, Tab. Anal. Fung. 1: fig. no. 57. 1883. MycoBank MBT387466.



Notes: The forked or sparsely branched basidiomata, with a tendency to be caespitose, and the presence of a distinct stipe, suggest that C. helenae is a synonym of Typhula crassipes. Although basidiomata of T. crassipes are usually simple, we have observed branched basidiomata as those depicted in the lectotype figure. Also, 2-spored basidia and incarnate tones are sometimes present in T. crassipes (Olariaga 2009). Corner (1950) compared C. helenae to P. gracile, but the latter lacks a stipe.



Ceratellopsis kubickae Pilát, Česká Mykol. 12(4): 217. 1958.



Typus: Czech Republic, prope Třeboň, ad folium putridum Salicis auritae [Salix aurita], 15 May 1958, Kubíčka (PRM 655767).



Notes: Pilát (1958) described C. kubickae as monomitic and compared it with P. gracile. Berthier (1976) investigated the type material and proposed that C. kubickae is a synonym of P. gracile, and that Pilát (1958) overlooked skeletal hyphae. In our opinion, the 2-spored basidia and the absence of a stipe in C. kubickae support it is a synonym of P. gracile.



Ceratellopsis mucosa (Berk. & M.A. Curtis) Corner, Ann. Bot. Mem. 1: 205. 1950.

Basionym: Typhula mucosa Berk. & M.A. Curtis, Grevillea 2(14): 18. 1873.



Typus: USA, South Carolina, Society Hill, in herb. mort., 1852, Carolina inf. No. 3832 (syntypes FH 596847, K).



Notes: The original description is very meagre, and we are unable to propose a reliable interpretation without checking type material. Corner (1950) failed also to provide a specific interpretation and stated that C. mucosa “may be Ceratellopsis, Pterula, or a rudimentary Pistillaria”.



Ceratellopsis rickii (Oudem.) Corner, Ann. Bot. Mem. 1: 205. 1950.

Basionym: Mucronella rickii Oudem., Ned. kruidk. Archf., 3 sér. 2(3): 667. 1902.

Synonym: Cnazonaria rickii (Oudem.) Donk, Meded. Bot. Mus. Herb. Rijks Univ. Utrecht 9: 99. 1933.



Typus: The Netherlands, Limburg, Valkenburg, in caulibus herbarum praesertim Asparagi off. [Asparagus officinalis], May 1901, J. Rick, herb. Oudemans (holotype L). Isotype: Bourdot & Galzin herbarium (PC !).



Notes: Jülich (1980) reduced C. rickii to a synonym of P. gracile after examining type material. We confirm this synonymy based on characters seen on the cited isotype.



Ceratellopsis rosella (Fr.) Corner, Ann. Bot. Mem. 1: 206. 1950.

Basionym: Pistillaria rosella Fr., Epicr. syst. mycol.: 587. 1838. [1836–1838].



Typus: No type specimen in the Fries herbarium (UPS). No original illustration.



Notes: The pink colour described in the protologue is almost unique to T. micans among typhuloid fungi and we thus agree with Berthier (1976) in considering C. rosella a synonym of T. micans.



Ceratellopsis sydowii (Bres.) Corner, Ann. Bot. Mem. 1: 206. 1950.

Basionym: Clavaria sydowii Bres. in Sydow, Hedwigia 35: (61). 1896.



Typus: Germany, Saxony, Muskau, O.L. Bergpark, ad ramulos Robiniae pseudoacaciae, Jul. 1895, P. Sydow, Mycoth. March. 4405 (syntypes CHRB, MIN, NCU).



Notes: The caespitose growth habit on dicot. bark, pale pink colour (“dilute carnei”), long basidia (24–26 μm) and spore size mentioned in the protologue (9–10 × 5–5.5 μm) suggest that C. sydowii is a synonym of T. crassipes.



Ceratellopsis terrigena Berthier, Bull. Soc. Linn. Lyon 43(6): 188. 1974.



Typus: France, Rhône, Lyon, Izeron, sur terre nue d'un talus en sous-bois, 7 Aug. 1966, CL. 29 (holotype G).



Notes: Due to its 1.5–3.5 μm broad medulla hyphae C. terrigena does not conform to Ceratellopsis as here defined. Also, the presence of striking protruding cystidia is unknown for any other species of Ceratellopsis. The shape of cystidia and the absence of clamp connections may suggest C. terrigena to be allied with Alloclavaria in the Rickenella clade (Hymenochaetales).



Ceratellopsis thujicola (Kauffman) Corner, Ann. Bot. Mem. 1: 206. 1950.

Basionym: Pistillaria thujicola Kauffman, Pap. Mich. Acad. Sci. 9: 207. 1929 [1928].



Typus: USA, Michigan, Alger: Rock River, on inner side of Thuja occidentalis on loose bark, 8 Sep. 1927, C.H. Kauffman (holotype MICH11745).



Notes: The up to 10 mm long branched basidiomata do not conform clearly to Ceratellopsis as here defined, and we thus exclude it from this genus. The type material should be examined to propose a more precise interpretation.



Ceratellopsis tremula (Sacc.) Corner, Ann. Bot. Mem. 1: 207. 1950.

Basionym: Pistillaria ferryi subsp. tremula Sacc. in Sacc. & D. Sacc., Syll. Fung. 17: 202. 1905.



Typus: Italy, Padova, horto botanico Patavino, ad fructum putremTrichosanthis anguineae [Trichosanthes sanguinea], ubi Botrytis vulgaris et Acremoniella atra, Feb. 1904 (syntype PAD).



Notes: The 3–5 mm long basidiomata, 2-spored basidia and 8–11 μm long spores conform to P. gracile, but the type specimen needs to be examined to confirm the synonymy. Although this synonymy is listed in Index Fungorum (2019, viewed on 11 June 2019), it has not been otherwise proposed to our knowledge.



Pleurotineae Aime, Dentinger & Gaya, Biol. J. Linn. Soc.: 10.1111/bij.12553, 16. 2015.



Phyllotopsidaceae Locquin ex Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, fam. nov. MycoBank MB831374.



Basidiomata pleurotoid or clavarioid and sometimes arising from a sclerotium. Spore deposit white to salmon pink. Hyphal system monomitic. Basidiospores hyaline, cylindrical, allantoid or subglobose, smooth, without iodine reactions. Cheilocystidia sometimes present in pleurotoid genera. Clamp connections present, rarely absent. Saprotrophic.



Type genus: Phyllotopsis E.-J. Gilbert & Donk ex Singer



Representative genera: Macrotyphula, Phyllotopsis and Pleurocybella.



Notes: Macrotyphula, Phyllotopsis and Pleurocybella were suggested to be closely related by Dentinger & McLaughlin (2006) and our analyses confirm that they form a monophyletic group. Despite this, no obvious synapomorphic characters support the relationship between the typhuloid Macrotyphula and the pleurotoid Phyllotopsis and Pleurocybella (Moncalvo et al. 2002). All three genera contain saprotrophic species, mostly lignicolous, and possess clamp connections.



Macrotyphula R.H. Petersen, Mycologia 64: 140. 1972. nom. cons. prop.



Type: Clavaria fistulosa Holmsk.: Fr. (synonym: Macrotyphula fistulosa (Holmsk. : Fr.) R.H. Petersen).



Synonyms: Sclerotium Tode, Fung. mecklenb. sel. 1: 2. 1790 : Fr., Syst. Mycol. 2: 246. 1822. nom. rej. prop. Type: Sclerotium complanatum Tode : Fr. (synonym: Typhula phacorrhiza (Reichard : Fr.) Fr.).

Clavariadelphus subgen. Typhulopsis Corner, Ann. Bot. Mem. 1: 692. 1950 [nom. inval. Art. 40.3, two species were indicated as type].



Macrotyphula megasperma (Berthier) Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, comb. nov. MycoBank MB831762.

Basionym: Typhula megasperma Berthier, Bull. Soc. Linn. Lyon 45: 78. 1976.



Macrotyphula phacorrhiza (Reichard : Fr.) Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, comb. nov. MycoBank MB831761.

Basionym: Clavaria phacorrhiza Reichard, Schriften Berlin. Ges. Naturf. Freunde 1: 315. 1780. [“Clauaria phacorhiza”] : Fr., Syst. mycol. 1: 495. 1821.

Synonyms: Sclerotium complanatum Tode, Fung. Mecklenb. Sel. 1: 5. 1790.

Typhula phacorrhiza (Reichard : Fr.) Fr., Observ. Mycol. 2: 298. 1818. [“Typhla”].

Phacorhiza filiformis Grev., Scott. Crypt. Fl. 2: 93. 1824 [nom. nov. based on Clavaria phacorrhiza Reichard]

Typhula phacorrhiza var. complanata (Tode) Sacc., Syll. Fung. 6: 745. 1888. [∗ complanata].



Typus: Lectotype of Clavaria phacorrhiza: Sowerby, Col. Fig. Eng. Fung. 2: tab. 233. 1798, as “phacorhiza”, designated by Olariaga & Salcedo (2013: 42). Lectotype of Sclerotium complanatum designated here: Tode, Fung. Mecklenb. 1: tab. 1, fig. 9. 1790. MycoBank MBT387906. Germany, Bayern, Oberbayern, Landkreis Miesbach, valley Kleinthal near Miesbach, in a garden under Ribes nigrum and Ribes rubrum, on wet litter of various plants, mostly of Ribes, 2 Mar. 1992, F. Brand, Microf. Exs. No. 49 (UPS, as Sclerotium complanatum; epitype of Sclerotium complanatum designated here; Isoepitypes in B, BPI, CANB, DAOM, FH, GZU, H, HAL, HMAS, LE, M, MA, NMW, PRM, TNS). MycoBank MBT389352.



Specimens examined: Austria, prope Tullnerbach, in silva “Wiener Wald, ad petiolos Fraxini excelsioris L., C. de Keissler, Krypt. Exs. 1840 (PC, as Sclerotium complanatum). France, Pyrénées atlantiques, Borce, Le Gave d'Aspe, on the ground, among Rubus idaeus and Myrrhis odorata, 12 Oct. 2014, J.C. Zamora & I. Olariaga, IO.14.200 (S); without locality, dans les bois, parmi les tas de feuilles pourries, Desmazières, Pl. Crypt. N. France, Ed. 1 536 (PC, as Sclerotium complanatum). Spain, Navarre, Basaburua, Orokieta, Loiandi, on the ground among needles under Picea abies, 27 Oct. 2017, I. Olariaga, J. Martín, J. Teres & J.M. Riezu, ARAN-Fungi 7446. Sweden, Skåne, Eriksdal, Vitabäckskällan Nature Reserve, on wet ground under Alnus, 3 Oct. 2014, N.-O. Nilsson & I. Olariaga, IO.14.167 (S); Uppland, Uppsala-Näs, Vreta, in a compost-heap, 18 Oct. 1975, L. Jonsell, Fung. Exs. Suec. 3249 (PC).



Typhula phacorrhiza var. heterogenea Berthier, Bull. Soc. Linn. Lyon 45: 197. 1976.



Typus: USA, Idaho, Priest River, inter foliis Alni tenuifoliae [Alnus tenuifolia], 19 Oct. 1920, Weir 16943 (CGE, holotype).



Notes: This taxon, due to its gelatinised sclerotia with normal epidermoid layer (Berthier 1976), may also belong to Macrotyphula. The type material appears to have lost its basidiomata (Berthier 1976) and we find it premature to place it in Macrotyphula.



Pterulaceae Corner, Beih. Nova Hedwigia 33: 194. 1970.



Type genus: Pterula Fr. : Fr.



Representative genera: Allantula, Coronicium, Dimorphocystis, Merulicium, Pterula, Pterulicium.



Pterula Fr. : Fr., Syst. Orb. Veg. 1: 90. 1825.

Basionym: Anthina [unranked] Pterula (Fr.) Fr., Syst. Mycol. 3: 285. 1832: Fr., idem.



Type: Pterula plumosa (Schwein. : Fr.) Fr., selected by Donk (1954: 472).



Pterulicium Corner, Ann. Bot. Mem. 1: 699. 1950. Type: Pterulicium xylogenum Corner

Synonyms: Ceratellopsis Konrad & Maubl., Icon. Select. Fung. 6: 502. 1937. Type: Ceratellopsis queletii (Pat.) Konrad & Maubl. (synonym Pterulicium gracile (Desm. & Berk.) Leal-Dutra, Dentinger, G.W. Griff.), typ. rej. prop.

Deflexula Corner, Ann. Bot. Mem. 1: 695. 1950. Type: Deflexula fascicularis (Bres. & Pat.) Corner



Notes: Since the type of Ceratellopsis nests in Pterulicium (Fig. 3), the correct name for Pterulicium is Ceratellopsis under the current nomenclatural rules. A proposal to preserve the current usage of Ceratellopsis and Pterulicium is, however, in preparation (see Discussion).



Pterulicium gracile (Desm. & Berk.) Leal-Dutra, Dentinger & G.W. Griff. in Leal-Dutra, Griffith, Neves, McLaughlin, McLaughlin, Clasen & Dentinger, IMA Fungus 11(2): 15. 2020.

Basionym: Typhula gracilis Desm. & Berk. in Berk, Ann. Nat. Hist., Ser. 1, 1: 202. 1838. [“Typhula? gracilis”].

Synonyms: Clavaria gracilis (Desm. & Berk.) P. Karst., Bidrag Kännedom Finlands Natur Folk 37: 181. 1882. [“Cl? gracilis”; nom. illeg., later homonym of Clavaria gracilis Bolton and C. gracilis Pers. : Fr., Art. 53].

Pistillaria gracilis (Desm. & Berk.) Pat., Tab. Anal. Fung. 6: 30. 1887.

Ceratella gracilis (Desm. & Berk.) Pat., J. Bot. (Morot) 3: 36. 1889.

Hirsutella gracilis (Desm. & Berk.) Pat., Essai tax. Hyménomyc.: 50. 1900.

Pterula gracilis (Desm. & Berk.) Corner, Ann. Bot. Mem. 1: 514. 1950.

Clavaria microscopica Malbr. & Sacc., Michelia 2(6): 42. 1880.

Clavaria aculina Quél., Compt. Rend. Assoc. Franç. Avancem. Sci. 9: 670. 1881. [“1880”]

Pistillaria aculina (Quél.) Pat., Tab. Anal. Fung. 6: 29. 1887.

Ceratella aculina (Quél.) Pat., Hymenomyc. Eur.: 137. 1887.

Cnazonaria aculina (Quél.) Donk., Meded. Ned. Mycol. Ver. 22: 97. 1933.

Pistillaria queletii Pat., Tab. Anal. Fung. 1: 22. 1882.

Ceratella queletii (Pat.) Pat., Hymenomyc. Eur.: 137. 1887. [valid combination following Arts. 41.3 and 38.14].

Ceratellopsis queletii (Pat.) Konrad & Maubl., Icon. Sel. Fung. 6: 502. 1937.

Typhula brunaudii Quél., Compt. Rend. Assoc. Franç. Avancem. Sci 13: 283. 1885. [1884].

Clavaria brunaudii (Quél.) Sacc., Syll. fung. 6: 730. 1888.

Ceratella ferryi Quél. & Fautrey, Revue. Mycol. (Toulouse) 15(57): 15. 1893.

Pistillaria ferryi (Quél. & Fautrey) Sacc., Syll. Fung. 11: 141. 1895.

Ceratella microscopica var. asphodeli Pat., Cat. Pl. Cell. Tunisie: 66. 1897.

Ceratellopsis asphodeli (Pat.) Corner, Ann. Bot. Mem. 1: 203. 1950.

Pistillaria attenuata Syd. & P. Syd., Hedwigia 39: (1). 1900.

Pistillaria acicula Bourdot & Galzin, Hymenomyc. France: 139. 1928. [“1927”].

Pistillaria juncicola Bourdot & Galzin, Hymenomyc. France: 138. 1928. [“1927”].



Typus: UK, without locality, ex Desmazières herbarium (PC, not found, lectotype designated in Corner (1950: 515) by type indication). Isolectotype: UPS (!).



Additional materials examined: France, Charente-Maritime, Saintonge, maïs [Zea mays], P. Brunaud, Quélet herbarium (PC !, lectotype of Typhula brunaudii designated here, MycoBank MBT387470); Côte-d'Or, Noidan, sur tiges séches de Coix lacryma-jobi, Fautrey, Jun. 1892, Fungi Sel. Gall. Exs. no 6203 (PC!, lectotype of Ceratella ferryi designated here, isolectotypes: BR, ILL, MIN, UPS, MycoBank MBT387491); Rhône, Saint Priest, les Bouys, vers le Souey, “sur joncs [Juncus] purrisants”, H. Bourdot, 27 Sep. 1918, Bourdot 24978 (PC !, lectotype of Pistillaria juncicola designated here, MycoBank MBT387471); Seine-Maritime, environs de Rouen, sur jonc [Juncus], Apr. 1880, A. Le Breton, Quélet herbarium (PC !, lectotype of Clavaria aculina designated here, MycoBank MBT387469); Seine-Maritime, Rouen, sur les joncs [Juncus] morts et humides, forêt de Noumare (?), A. Malbranche, (PC !, lectotype of Clavaria microscopica designated here, MycoBank MBT387468). Germany, Brandenburg, Finkenkrug pr. Nauen, ad folia culmosque graminum, Calamagrostidis epigeii [Calamagrostis epigejos], Agrostidis albae [Agrostis alba] etc., Mycoth. Mar. no. 4803 (S F15411 !, lectotype of Pistillaria attenuata designated here, isolectotypes: FH00608505 (!), MICH, MycoBank MBT387678). Lectotype of Pistillaria queletii designated here: Patouillard, Tab. Anal. Fung. 1: fig. 45. 1883. MycoBank MBT389354. Sweden, Skåne, Kristianstads kommun, Balsberget Nature Reserve, on dead standing Juncus effusus stalks, at damp place, N.-O. Nilsson & I. Olariaga, 2 Oct. 2014, IO.14.142 (S, epitype of Pistillaria queletii designated here, MycoBank MBT387907).



Notes: In order to contribute to nomenclatural stability, an epitype specimen that represents P. gracile is proposed above for Pistillaria queletii (see Discussion). No good and recent specimen of P. gracile from France was available to epitypify C. queletii. Nevertheless, European material of P. gracile is morphologically and genetically homogeneous — ITS and 28S sequences available from France, Germany and Canada (CBS 309.79, CBS 325.58, CBS 554.85) are identical or nearly so to the sequences obtained by us from Sweden — and therefore we epitypify C. queletii using a specimen of P. gracile collected in Sweden.



Sarcomyxaceae Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, fam. nov. MycoBank MB831375.



Basidiomata pleurotoid, with gelatinous context in pileus. Gills slightly decurrent, crowded, forking. Stem lateral, floccose. Spore deposit white. Basidiospores cylindrical to allantoid, amyloid. Basidia claviform, (2–)4-spored, clamped. Cheilo- and pleurocystidia fusiform to clavate, more or less thick-walled. Pileipellis and part of trama gelatinised. Clamp connections present. Saprotrophic, lignicolous.



Type genus: Sarcomyxa P. Karst.



Only genus: Sarcomyxa.



Notes: The family contains a single genus with unique pleurotoid basidiomata, gelatinised pileipellis, fusiform to clavate cheilo- and pleurocystidia and amyloid spores (Knudsen & Vesterholt 2012). Due to its isolated position within the Pleurotineae (Fig. 2, Fig. 3), a new family is coined to accommodate Sarcomyxa.



Typhulaceae Jülich, Biblioth. Mycol. 85: 393. 1982 [“1981”]



Type genus: Typhula (Pers. : Fr.) Fr.



Typhula (Pers.) Fr., Obs. Mycol. 2: 296. 1818: Fr., Syst. Mycol. 1: 494. 1821, nom. cons. prop.

Basionym: Clavaria [unranked] Typhula Pers. : Fr., Syn. Meth. Fung. 1: XVIII. 1801

Type: Typhula incarnata Lasch, typ. cons. prop.

Synonyms: Pistillaria Fr., Syst. Mycol. 1: 496. 1821: Fr., idem. Type: Pistillaria micans (Pers. : Fr.) Fr., selected by Clem. & Shear, Gen. Fungi: 345. 1931 (synonym Typhula micans (Pers. : Fr.) Fr.).

Cnazonaria Corda in J. Sturm, Deutschl. Fl., Pilze 2: 55. 1829. Type: Clavaria setipes Grev. (synonym Typhula gyrans (Batsch : Fr.) Fr.).

Scleromitra Corda in Sturm, Deutschl. Fl., 3 Abt., 2: 59. 1829. Type: Scleromitra coccinea Corda (synonym T. micans (Pers. : Fr.) Fr.).

Phacorhiza Pers., Mycol. Eur. 1: 192. 1822 : Fr., Syst. Mycol. 3 (Index): 140. 1832. Type: Phacorhiza sclerotioides (Pers. : Fr.) Pers. (synonym Typhula sclerotioides (Pers. : Fr.) Fr.).

Pistillina Quél., Compt. Rend. Assoc. Franc. Avancem. Sci. 9: 671. 1881. [“1880”]. Type: Pistillina hyalina Quél. (synonym Typhula subhyalina Courtec.).

Sphaerula Pat., Tab. Anal. Fung. 1: 27. 1883. Type: Sphaerula capitata Pat. (synonym Typhula capitata (Pat.) Berthier)

Gliocoryne Maire, Bull. Soc. Bot. France 55: 121. 1909. Type: Clavaria uncialis Grev. (synonym Typhula uncialis (Grev.) Berthier)

Dacryopsella Höhn., Anz. Kaiserl. Akad. Wiss. Wien, Math.-Naturwiss. Kl., Abt. 1, 124: 50. 1915. Type: Dacryopsis typhae Höhn. (synonym T. subhyalina Courtec.).

Tygervalleyomyces Crous, Persoonia 39: 387. 2017. Type: Tygervalleyomyces podocarpi Crous.



New combinations in Typhula 



Typhula podocarpi (Crous) Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen comb. nov. MycoBank MB831376.

Basionym: Tygervalleyomyce podocarpi Crous, Persoonia 39: 387. 2017.



Notes: The asexual and only known morph of T. podocarpi, described from South Africa, conforms to that of Typhula crassipes, described from Germany (Berthier 1976). The ITS region of T. podocarpi differs in 23 positions from that of European specimens of T. crassipes and we thus consider T. podocarpi to be a separate species.



Rickenellaceae Vizzini, Micol. Veg. Medit. 25(2): 144. 2010.



Type genus: Rickenella Raithelh.



Representative genera: Alloclavaria, Atheloderma, Blasiphalia, Bryopistillaria, Cantharellopsis, Contumyces, Cotylidia, Ginnsia, Globulicium, Gyroflexus, Loreleia, Muscinupta, Odonticium, Peniophorella, Resinicium, Rickenella, Sidera, Skvortzovia and Tsugacorticium. Excluded from Rickenellaceae: Repetobasidium.



Notes: Genera in the Rickenella clade have been assigned to the Repetobasidiaceae (Zhang et al. 2018), often left without family assignation (Kirk et al., 2008, Knudsen and Vesterholt, 2012), or included in the family Rickenellaceae (Begerow et al. 2018). Our analyses suggest that Repetobasidium does not nest in the Rickenella clade, and Repetobasidiaceae cannot therefore be used to accommodate genera in the Rickenella clade. Consequently, we adopt Rickenellaceae as the correct placement for genera in this clade, excluding Repetobasidium so that Rickenellaceae is not superfluous as when erected by Vizzini (2010).



Bryopistillaria Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, gen. nov. MycoBank MB831377.



Etymology: From ancient Greek (“bryon”, moss), referring to its habitat on bryophytes, and from Pistillaria, referring to its similarity with several species placed in that genus.



Biotrophic on mosses, and maybe in addition saprobic on dead leaves and culms. Basidiomata gregarious or fasciculate (2–5 basidiomata), simple clavarioid, 0.6–1 mm high, initially lanceolate and with sterile apex, then cylindrical or claviform, with rounded fertile apex, white. Stipe short or absent, cylindrical, glabrous or pubescent. Hyphal system monomitic. Basidiospores without iodine reactions, smooth. Basidia claviform, 16–21 μm long. Medulla hyphae parallel-arranged, cylindrical, septate, thin-walled, 3–4 μm broad, without iodine reactions. Clamp connections absent.



Type: Bryopistillaria sagittiformis (Pat.) Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen



Bryopistillaria sagittiformis (Pat.) Olariaga, Huhtinen, Læssøe, J.H. Petersen & K. Hansen, comb. nov. Fig. 7. MycoBank MB831378.

Fig. 7.

Bryopistillaria sagittiformis (epitype, IO.15.85, S). A. Basidioma growth habit. B. Close-up of basidiomata. C. Basidioma observed using a light microscope. D. Close-up of basidioma apex. E. Basidiospores. F. Basidia. G. Hymenium section showing a subhymenium with globose to sugblobose cells. H. Subhymenium cells. I. Thin-walled septate medullar hyphae. J. Caulinar hair. K. Crystals. Mounting media were Melzer's reagent (H, K) and Congo Red in ammonia (C–G, I–J). Scale bars: C = 100 μm; D = 50 μm; E–K = 10 μm. Photographs I. Olariaga, except B–C by J.H. Petersen.

Basionym: Pistillaria sagittiformis Pat., Tab. Anal. Fung. 1: 26. 1883 [“sagittæformis”]

Synonym: Ceratellopsis sagittiformis (Pat.) Corner, Ann. Bot. Mem. 1: 206. 1950. [“sagittæformis”].



Basidiomata gregarious or caespitose in groups of 2–5 basidiomata, 0.7–1.2 mm high, simple, with a short stipe. Fertile part narrowly claviform, sharply delimited from the stipe, white, 0.6–0.1 × 0.15–0.3 mm. Stipe short, cylindrical, glabrous or with sparse hairs, hyaline white, 0.1–0.4 × 0.1–0.2 mm. Subiculum spreading out on the substratum among basidiomata. Apex pointed and sterile in very young basidiomata, hyaline white, then obtuse and fertile. Basidiospores ellipsoid, sometimes in tetrads, hyaline, smooth, without iodine reactions, 4.5–6.5(–8) × 3–3.5(–4) μm. Basidia claviform, (1–2–)4-spored, 16–23 × 4.5–7 μm, clampless. Subhymenium composed of globose to subglobose hyphae, thin-walled, hyaline, 4–10(–12) μm broad. Generative hyphae cylindrical to fusiform, hyaline, thin-walled, clampless, 2.5–6(–9) μm broad, without iodine reactions. Hyphae on the stipe surface cylindrical, thin-walled, clampless, 3–3.5 μm broad. Caulinar hairs sparse, cylindrical, thin-walled, up to 50 × 3 μm. Subiculum formed by cylindrical hyphae, thin-walled, straight, branching at right angles, clampless, 3–4 μm broad. Skeletal hyphae absent. Crystals sometimes present among the medulla hyphae, bipyramidal or sphaeroid. Attempts to obtain cultures from shed spores on MEA unsuccessful.



Typus: Lectotype designated here: Patouillard, Tab. Anal. Fung. 1: fig. 56. 1883. MycoBank MBT389355. Estonia, Otepää, Karula National Park, Peräjärve forest trail, on living Pleurozium schreberi, 13 Sep. 2015, I. Olariaga, IO.15.85 (S, epitype designated here; isoepitype in UPS). MycoBank MBT387918.



Known distribution: Denmark, Estonia, Finland, France, Sweden.



Additional materials examined: Denmark, Lolland, Biowide plot 120, Hejrede Sø, 5 Nov. 2014, T. Læssøe & T. Smidth, DMS-695059 (C); Sjælland, Allindelille Fredskov, on dead stem of Alnus, 20 Oct. 1977, H. Knudsen, C-F-124736; Amager Strandpark, on moss, 17 Nov. 2014, T. Læssøe, C-F-113951; Asserbo Plantage, on damp Juniperus bark and living mosses, 28 Feb. 2019, O. Martin, DMS-10005573 (C); Vestskoven, on damp Juniperus bark and mosses, 14 Feb. 2018, T. Kehlet, DMS-9242450 (C); Biowide plot 079, Melby Hede, 6 Nov. 2014, T. Læssøe, DMS-695405 (C); Biowide Plot 070, Gjessøvej, on moss, 31 Aug. 2015, T. Borgen & T. Læssøe, C-F-114679; Biowide plot 120, Hejrede Sø, base of Poaceae plant, 5 Nov. 2014, T. Læssøe & T. Smidth, C-F-114417; Strødam Reservatet, on mosses, rotten leaves and bark, 8 Nov. 2003, T. Læssøe, DMS-398331(C); Jægersborg Dyrehave, on moss and algae, 20 Jun. 1998, T. Læssøe, DMS-384562 (C-F-38168); Møns Klinteskov, v. Nælderenden, on moss on branch in damp hole, 23 Oct. 1971, H. Knudsen, C-F-94572; Stabjerggård, on Tortula, 14 Nov. 1976, H. Knudsen, C-F-94573. Finland, Pohjois-Häme, Laukaa, Hallalähde, on water dripping hillside west of the spring, on stock covered with moss, abundant on Pleurozium schreberi, 14 Sep. 2004, T. Rämä (TUR 178089). France, Pyrénées atlantiques, Escot, Le Barescou, on living mosses, 8 Oct. 2016, I. Olariaga (ARAN-Fungi 4625). Sweden, Dalarna, Särna, ca. 1.5 km W from Kryptjärnen, on living Thuidium tamariscinum and Plagiomnium, spreading on a dead herbaceous culm, 31 Aug. 2015, I. Olariaga, IO.15.41 (S); Skåne, Eriksdal, Vitabäckskällan Nature Reserve, on living leaves of Scorpidium cossonii, 3 Oct. 2014, N.-O. Nilsson & I. Olariaga, IO.14.164 (S); Skåne, Tomelilla, Årupkärrets Nature Reserve, on living Scorpidium cossonii, in a fen, 3 Oct. 2014, N.-O. Nilsson & I. Olariaga, IO.14.163 (S); Uppland, Uppsala, the cemetery wall, southeast corner adjacent to Carolinaparken, on low mosses (Tortula ruralis), 12 Sep. 1932, S. Lundell (UPS F-152985, as Ceratellopsis cf. sagittiformis).



Notes: The original plate of B. sagittiformis shows a fungus with a fertile apex, 2-spored basidia and aseptate medulla hyphae reminiscent of skeletal hyphae. Corner (1950) suggested this plate might correspond to a Pterula species, but this view cannot be verified, as no type specimen appears to exist in the Patouillard herbarium (FH, PC). Instead, we interpret B. sagittiformis, as a species with obtuse fertile basidiomata at least when not extremely young, medulla hyphae 3–4 μm broad, lacking clamp connections and occurring usually, though apparently not strictly, on living mosses (Hansen & Knudsen 1997). It is possible that mosses are always present but not necessarily act directly as substrate for the basidiomata. Accordingly, we propose an epitype specimen to stabilise its current interpretation (Corner, 1950, Hansen and Knudsen, 1997).



Key to genera that contain species that can be considered typhuloid

• 1.Lichenised; growing on a thallus containing green algaes……………………………………………………………………Multiclavula
• 1.Non-lichenised; not associated with green algae…………………………………………………………………………………………2
• 2.Basidia with transverse septa; on living bryophytes……………………………………………………………Eocronartium muscicola
• 2.Basidia without septa; on various substrates incl. bryophytes ……………………………………………………………………………3
• 3.Clamp connections verticillate on context hyphae…………………………………………………………………Lutypha sclerotiophila
• 3.Clamp connections absent or simple when present………………………………………………………………………………………4
• 4.With a sclerotium………………………………………………………………………………………………………………………………5
• 4.Without a sclerotium..…………………………………………………………………………………………………………………………7
• 5.With skeletal hyphae; smell phenolic when fresh…………………………………………unbranched forms of Pterula sclerotiicola
• 5.Without skeletal hyphae; smell not phenolic (living basidiomata)………………………………………………………………………6
• 6.Sclerotium compressed; sclerotial rind normal (i.e. with cells rooting in the medulla) with medulla gelatinised; basidiomata brown; fertile part cylindrical……………………………………………………………………Macrotyphula phacorrhiza and M. megasperma
• 6.Sclerotium usually not compressed, sclerotial rind inverse (i.e. with cells not rooting in the medulla), if normal, with medulla rarely gelatinised; basidiomata brown or with other colours, fertile part cylindrical to convex……………………………………Typhula p.p.
• 7.With skeletal hyphae.…………………………………………………………………………………………………………………………8
• 7.Without skeletal hyphae…………………..…………………………………………………………………………………………………9
• 8.Stipe absent; protruding hymenial cystidia producing conidia; basidia 2-spored; spores 9–16 × 3.5–7 μm; smell phenolic when fresh…………………………………………………………………………………………………………………………Pterulicium gracile
• 8.Stipe short; hymenial cystidia absent; basidia 1–4-spored; spores smaller; smell not phenolic…………………Ceratellopsis p.p.
• 9.Spores ornamented…………………………………………………………………………………………………………Ramariopsis p.p.
• 9.Spores smooth.………………………………………………………………………………………………………………………………10
• 10.With hymenial cystidia………………………………………………………………………………………………………………………11
• 10.Without hymenial cystidia...…………………………………………………………………………………………………………………13
• 11.Fertile part more or less cylindrical; terricolous; clamps absent; caulocystidia absent……………………“Ceratellopsis” terrigena
• 11.Fertile part globose to spathulate; on dead plant remnants; clamp connections sometimes present; caulocystidia sometimes present..………………………………………………………………………………………………………………………………………12
• 12.Spores ellipsoid, fusiform or sigmoid……………………………………………………………………………………………Physalacria
• 12.Spores broadly ellipsoid to subglobose……………………………………………………………………Actiniceps (= Chaetotyphula)
• 13.Basidiomata < 2 mm high; apex sterile and pointed at least in young basidiomata…………………………………………………14
• 13.Basidiomata higher, if < 2 mm high then apex fertile even in young basidiomata……………………………………………………15
• 14.Medulla hyphae < 2.5 μm broad; subhymenial hyphae not swollen, < 2.5 μm broad; on dead plant remnants; clamps (always?) present………………………………………………………………………………………………………………………Ceratellopsis p.p.
• 14.Medulla hyphae 2.5–6(–9) μm broad; subhymenial hyphae globose to subglobose, 4–10(–12) μm broad; often on living mosses; clamps absent…………………………………………………………………………………………Bryopistillaria sagittiformis
• 15.Basidiomata pale brown; usually > 10 mm high; spores inamyloid……………………………………………………Macrotyphula p.p.
• 15.Basidiomata if > 10 mm high then colour not brown; spores amyloid or not…………………………………………………………16
• 16.Clamps present and abundant on hyphae in the context………………………………………………………………………………17
• 16.Clamps absent or restricted to basidia and loop-like……………………………………………………………………………………19
• 17.Not positively geotropic; fertile part and stipe usually sharply delimited; growing usually on dead leaves or stems of plants………………………………………………………………………………………………………………………………Typhula p.p.
• 17.Usually positively geotropic; fertile part and stipe not clearly differentiated; growing on highly decayed wood or polypores..…………………………………………………………………………………………………………………………………………18
• 18.With gloeocystidia; spores subglobose………………………………………………………………………………………Dentipratulum
• 18.Without gloeocystidia; spores ellipsoid……………………………………………………………………………………………Mucronella
• 19.Basidiomata < 1.5 mm high; stipe with 150–250 μm long erect hairs with obtuse ends; on dead wood………………………………………………………………………………………………………………………Hirticlavula elegans
• 19.Basidiomata larger, hairs absent or considerably shorter; terrestrial or on leaves and herbaceous remnants of plants.……………………………..……………………………………………………………………………………………………………20
• 20.On plant remnants; spores usually amyloid……………………………………………………………………………………Typhula p.p.
• 20.Terrestrial; spores non-amyloid………………………………………………..………………………………………………………Clavaria

Discussion

Evolution of typhuloid fungi and family delimitation in the Agaricales and the Pleurotineae

This study provides the most robust phylogenetic hypothesis for typhuloid fungi to date, and it resolves for the first-time relationships with other genera in the Agaricales. Terminal nodes recovered in our Agaricales analyses using ML and Bayesian approaches are consistent to a great extent with those obtained by Matheny et al. (2006). In addition, several more basal nodes received support when analysed using a Bayesian method (Fig. 2, Fig. 3), while ML bootstrap values were low for most of those. As RAxML does not allow for a free model-choice, the same dataset was analysed using IQ-TREE (Nguyen et al. 2015) and Garli (Zwickl 2006), but the supported topology was identical and bootstrap values were similar to those obtained in RAxML. It has long been known that Bayesian PP tend to be higher than ML bootstrap values (e.g. Susko 2009), and have been claimed to refer to different properties of phylogenetic confidence (García-Sandoval 2014). Although our dataset is the most comprehensive ever assembled for typhuloid fungi, it might still contain too little molecular characters to reconstruct the comparatively deep divergences among clades. In any case, it was highly expected that novel supported topologies would be recovered for the first time when more taxa were added to the analyses, even if many nodes so far only received support in the Bayesian analyses.

Typhulaceae, Pleurotaceae, Pterulaceae, Stephanosporaceae, Sarcomyxa, Pleurocybella and Phyllotopsis are resolved as a monophyletic group for the first time (Fig. 2, Fig. 3), corresponding to the Pleurotineae (Dentinger et al. 2016). Our results confirm that Sarcomyxa and the Typhulaceae belong to Pleurotineae as anticipated by Dentinger et al. (2016). The back-bone of the Pleurotineae phylogeny is fully resolved (Fig. 3) and suggest that Macrotyphula and Typhula, with a typhuloid basidioma configuration, might have evolved from a pleurotoid ancestor. The phylogenetic relationships of Phyllotopsis, Pleurocybella and Sarcomyxa, of debated family placement, are also resolved in our Bayesian Pleurotineae phylogeny (Fig. 3). These three pleurotoid genera have been placed, not always together, in families containing white-spored agarics, such as Marasmiaceae, Mycenaceae, Pleurotaceae and Tricholomataceae (e.g. Ju¨lich, 1982, Moncalvo et al., 2000, Kirk et al., 2008, Begerow et al., 2018), or even Pterulaceae (Begerow et al. 2018), but previous phylogenies did not support any of these family placements (e.g. Matheny et al., 2006, Binder et al., 2010). Based on our phylogenies and the high Bayesian PP (Fig. 2, Fig. 3), we propose the new family Sarcomyxaceae to encompass Sarcomyxa and validate the family Phyllotopsidaceae to accommodate Macrotyphula, Phyllotopsis and Pleurocybella. On the other hand, Pterulaceae and Radulomycetaceae, recently split sister families (Leal-Dutra et al. 2020, contains an assemblage of fungi with clavarioid, corticioid and polyporoid basidioma types (Zhao et al. 2016), monomitic or dimitic, defined as “morpho-anatomically a very diverse family with colourless spores” (Begerow et al. 2018), but well-supported in molecular phylogenies (Fig. 3; Matheny et al., 2006, Binder et al., 2010). All members of Pterulaceae and Radulomycetaceae studied when fresh (Aphanobasidium filicinum, Pterula subulata, Pterulicium gracile, P. sclerotiicola, Radulomyces confluens, R. molaris, and R. rickii had a distinct phenolic or naphthalene odour, as sometimes described for P. multifida (e.g. Petersen 1999). It is thus suggested here that such an odour, produced by a probably unidentified fungal metabolite, may be a synapomorphic character of Pterulaceae, but further species must be tested to draw a final conclusion.

According to our results, the hygrophoroid clade as recovered by Matheny et al. (2006), is not monophyletic, because the Hygrophoraceae, the Pleurotineae and Xeromphalina campanella, all previously assigned to the hygrophoroid clade (Matheny et al. 2006), are encompassed in three independent lineages within the Agaricales (Fig. 2). The position of the Hygrophoraceae inferred from our analyses is not consistent with the 208-locus phylogeny by Dentinger et al. (2016), which placed Hygrocybe conica (Hygrophoraceae) and Clavaria fumosa (Clavariaceae) in a monophyletic group described as the Hygrophorineae. The dataset employed by Dentinger et al. (2016) contained 36 taxa of the highly diverse Agaricales and only a single taxon of the Hygrophoraceae. Phylogenetic analyses of a matrix with few taxa, even when the number of overall characters is large, can be subject to strong systematic biases and can be susceptible to long-branch attraction (Heath et al. 2008). In our preliminary analyses, H. coccinea nested in Clavariaceae when no other Hygrophoraceae were included in the matrix. With the addition of a few taxa of the Hygrophoraceae (Fig. 2), Clavariaceae and Hygrophoraceae do not form a monophyletic group, but are suggested to be successive sister taxa to the rest of the Agaricales. Our data indicates that Dentinger et al. (2016) recovered H. conica and C. fumosa in a monophyletic clade due to a long-branch attraction artifact and we anticipate that this clade will no longer be resolved when more species of Hygrophoraceae are included in phylogenomic analyses of large multigene datasets. Following our phylogenetic hypothesis, we propose the new suborder Clavariineae to accommodate the Clavariaceae.

Typhula phacorrhiza is a synonym of Sclerotium complanatum that nests in Macrotyphula

Earlier hypotheses on the phylogenetic position of Typhula and Typhulaceae relied on a misidentified specimen of T. phacorrhiza (DSH96-059; Pine et al. 1999) that belongs to the Macrotyphula juncea species complex (Olariaga et al. in prep.). Therefore, this is the first time that T. phacorrhiza is included in a multigene phylogenetic study. As previously suggested, based on morphology (Olariaga & Salcedo 2013), T. phacorrhiza and Sclerotium complanatum belong to Macrotyphula. The bulk of species of Typhula form a distinct separate clade (referred to as the Typhula-core clade). Thus, our analyses confirm that the selection of T. phacorrhiza as type of Typhula is unfortunate (Berthier, 1976, Olariaga and Salcedo, 2013), also for the sake of nomenclatural stability. The examination of material deposited in herbaria under S. complanatum showed that this name is usually applied to sclerotia of T. phacorrhiza (e.g. Pl. Crypt. N. France, ed. 1, no 536; Microf. Exs. no 49; Krypt. Exs. no 1840; see material examined under T. phacorrhiza) and that S. complanatum is a synonym of T. phacorrhiza as proposed long ago (Remsberg 1940). Furthermore, the Typhula-core clade contains the types of all genera segregated from Typhula at some point. Based on analyses of a more inclusive species sampling of Typhula (Olariaga et al., in prep), we consider it more appropriate to merge all those genera, as done by some authors (Berthier, 1976, Knudsen and Vesterholt, 2012), rather than splitting Typhula into several genera that could be recognised only with great difficulty.

A strict application of nomenclatural rules in the light of our phylogenetic hypothesis (Fig. 2, Fig. 3) would result in a high number of undesirable name changes. The correct generic name for species of Macrotyphula and T. phacorrhiza would be Sclerotium. However, the adoption of Sclerotium for Macrotyphula species would be misleading, because nearly all Macrotyphula species lack sclerotia and Macrotyphula is a well-established name. At the same time, species in the Typhula-core clade would need to be transferred to Pistillaria, the oldest alternative genus name for the group. Pathogenic species of Typhula, such as T. idahoensis, T. incarnata or T. ishikariensis, on which extensive literature has been published, would undergo name changes. Also, the epithet of T. incarnata would need to be changed to avoid creating a later illegitimate homonym of Pistillaria incarnata Desm. In order to preserve nomenclatural stability, two proposals are in preparation to conserve: 1) Typhula with T. incarnata as conserved type, and 2) Macrotyphula against Sclerotium (Olariaga et al. unpubl.). In accordance with our proposals, we combine in Macrotyphula two closely related taxa treated by Berthier in Typhula subgen. Typhula: T. phacorrhiza and T. megasperma.

Ceratellopsiss. auct. is polyphyletic and misapplied

Despite our efforts to find good material, very few specimens of Ceratellopsis were available for this study. Besides those types examined by Berthier (1976), only a few more type specimens of Ceratellopsis could be located and examined. The type specimens of most names placed in Ceratellopsis appear to be lost and can only be interpreted through their protologues. Most non-type specimens of Ceratellopsis were characterised by having a central medulla of narrow, thick-walled hyphae, a poorly differentiated subhymenium of cylindrical < 2 μm broad hyphae, a sterile basidioma apex, a well-delimited stipe, basidia < 20 μm long and spores < 8 μm long. Some of these collections had skeletal hyphae in the medulla, as also observed in the type specimens of C. acuminata, while other specimens assigned to C. aculeata and C. mucedinea had scarcely septate hyphae with thinner walls. Specimens identified as C. sagittiformis differed in having broader (up 3–4(–8) μm), more often septate medulla hyphae, a well differentiated subhymenium with swollen, globose to subglobose hyphae (4–10(–12) μm) and a basidioma apex becoming fertile. Three type specimens (C. attenuata, C. equiseticola and C. rickii) and several other specimens filed under the names C. aculeata and C. acuminata represent P. gracile, because they possessed skeletal hyphae, 2-spored basidia, acuminate cystidia and lacked a stipe. As earlier suggested (Corner, 1950, Berthier, 1976), several names originally described or combined in Ceratellopsis represent in fact P. gracile.

This study provides the first molecular data of Ceratellopsis. It resolves the genus as polyphyletic, with species belonging to both the Clavariaceae and the Hymenochaetales. Among the specimens sampled for the molecular phylogenetic study, those with a sterile pointed apex and narrow thick-walled medulla hyphae nest in the Clavariaceae. This position is supported by the fact that tiny clavarioid basidiomata are also known in other Clavariaceae, such as in Hirticlavula (Petersen et al. 2014) and Mucronella (Birkebak et al. 2013). Narrow hyphae on the base of the stipe, typical in Clavariaceae (Olariaga 2009), have also been observed in species of Ceratellopsis. For the first time, we demonstrate that skeletal hyphae are present in some species of Ceratellopsis and that it is not a unique character for Pterulaceae among typhuloid fungi. The species of Ceratellopsis placed in Clavariaceae differ from P. gracile in having basidia < 20 μm long, a well-delimited stipe and in lacking protruding acuminate cystidia. This lineage of Ceratellopsis conforms to Corner’s (1950) concept of Ceratellopsis, i.e. “Ceratellopsis aculeata and the species which appear to resemble it”, except for the presence of skeletal hyphae in some species. The examination of a specimen identified as C. aculeata by Corner (PC), with very narrow, scarcely septate medulla hyphae, confirms this view. In accordance with this, we conclude that C. corneri and C. terrigena, having medullar hyphae 4–6 μm and 1.5–3.5 μm broad, respectively, do not belong to this lineage and must be placed elsewhere (see Taxonomy).

The inclusion of C. sagittiformis in the Rickenella clade of the hymenochaetoid clade is a novel and unexpected find although material identified as C. sagittiformis is often associated with living bryophytes, as several members of the clade are (Korotkin et al. 2018). The Rickenella clade encompasses fungi with a diverse basidioma configuration (agaricoid, clavarioid, cyphelloid, thelephoroid, corticioid, etc.) that often are associated with mosses (Larsson et al. 2006). Within the Rickenella clade, C. sagittiformis resembles Muscinupta laevis in having white basidiomata, in growing on living bryophytes and in lacking clamp connections (Eriksson & Ryvarden 1975, as Cyphellostereum laeve), but our phylogenetic analyses lack support to confirm a close relationship. Phylogenetic relationships within the Rickenella clade were previously explored using only ribosomal nuclear markers (5.8S and 28S; Larsson et al. 2006), and only recently using also the RPB2 region. Even with the addition of the 18S and the RPB2 regions and more taxa to the analyses of the hymenochaetoid clade, relationships within the Rickenella clade remain largely unresolved (Korotkin et al. 2018, Fig. 5). The three specimens of C. sagittiformis have identical sequences and formed a distinct lineage. Based on this and the fact that C. sagittiformis is the only bryophilous, reduced clavarioid species known to belong to the Rickenella clade, we propose the new genus Bryopistillaria to accommodate it (see Taxonomy).

Proposing a reliable and stable interpretation of C. queletii, type of Ceratellopsis, is necessary to be able to provide a solid interpretation of Ceratellopsis. The name Ceratellopsis queletii appears not to have been employed since its original description (Patouillard 1883). Regrettably, no type specimen exists in PC and FH (G. E. Tocci pers. comm.) and no original specimen is likely to be present in any other fungarium. The absence of a stipe, the sterile apex, the 2-spored basidia and the presence of protruding acuminate cystidia, clearly depicted in the original illustration of C. queletii selected here as lectotype, are characteristic of P. gracile (Corner, 1950, Berthier, 1976, Jülich, 1980). The spore size estimated by Corner from the original Patouillard plate of C. queletii is smaller (6 × 3 μm) than the range we have estimated (8–8.5 × 4.5–5 μm) and the size reported by Quélet (“8 μm?”, 1884) for C. queletii. Spores in P. gracile are generally reported as slightly larger than our measure estimates from the Patouillard plate, but those are almost within the ranges published for P. gracile: 9–16 × 4–7 μm (Corner 1950), 10.5–12.5 × 5.5–5.6 μm (Berthier 1976), 10–14 × 5.5–6.5 μm (Jülich 1980) and 8–11 × 5–7 μm (Daniëls & Moreno-Arroyo 2007). Based on all this, we consider C. queletii a synonym of P. gracile, as already Corner (1950) suggested.

Leal-Dutra et al. (2020), using one of the specimens of P. gracile employed in our analyses (CBS 309.79), showed that it belongs to the Pterulicium clade. This taxonomic conclusion reduces Pterulicium, as recently circumscribed, to a later synonym of Ceratellopsis and the fourty-six names combined in Pterulicium (Leal-Dutra et al. 2020), besides its type Pterulicium xylogenum, would have to be combined again in Ceratellopsis. In addition, a new genus name would be required for C. acuminata and C. aculeata. In order to avoid nomenclatural changes that may cause confusion, a proposal to conserve Ceratellopsis with C. acuminata as conserved type is in preparation. The acceptance of this proposal would preserve the current usage of Ceratellopsis and Pterulicium, typified by P. xylogenum, a presumed causal agent of culm rot disease of bamboo (Harsh et al. 2005) and possibly also of sugarcane (Corner 1952).

Conclusions

This study reveals that typhuloid fungi appeared several times among the Agaricomycetes and contributes to the understanding of fungal evolution and shifts of basidioma configuration. Novel phylogenetic hypotheses are provided for several groups of typhuloid fungi and pleurotoid agarics, and pertinent family and generic classifications are proposed. Future phylogenomic analyses will hopefully incorporate more taxa, including typhuloid fungi, and will serve to further test our phylogenetic hypotheses.