An Updated Phylogenetic Assessment and Taxonomic Revision of Perenniporia sensu lato (Polyporales, Basidiomycota)

Perenniporia is an important genus of Polyporaceae. In its common acceptation, however, the genus is polyphyletic. In this study, phylogenetic analyses on a set of Perenniporia species and related genera were carried out using DNA sequences of multiple loci, including the internal transcribed spacer (ITS) regions, the large subunit nuclear ribosomal RNA gene (nLSU), the small subunit mitochondrial rRNA gene (mtSSU), the translation elongation factor 1-α gene (TEF1) and the b-tubulin gene (TBB1). Based on morphology and phylogeny, 15 new genera, viz., Aurantioporia, Citrinoporia, Cystidioporia, Dendroporia, Luteoperenniporia, Macroporia, Macrosporia, Minoporus, Neoporia, Niveoporia, Rhizoperenniporia, Tropicoporia, Truncatoporia, Vanderbyliella, and Xanthoperenniporia, are proposed; 2 new species, Luteoperenniporia australiensis and Niveoporia subrusseimarginata, are described; and 37 new combinations are proposed. Illustrated descriptions of the new species are provided. Identification keys to Perenniporia and its related genera and keys to the species of these genera are provided.

The current phylogenetic analysis confirmed that Perenniporia is polyphyletic, and some monophyletic clades have been separated from Perenniporia s. l. and recognized as independent genera [3,[35][36][37]. Based on such characters as the acyanophily and amyloidity New sequences are shown in bold.
ML studies were conducted with RAxML-HPC through the Cipres Science Gateway (https://www.phylo.org, accessed on 12 June 2022) and involved 1000 ML searches under the GTRGAMMA model. Only the maximum likelihood best tree from all searches was kept. In addition, 1000 rapid bootstrap replicates were run with the GTRCAT model to assess the reliability of the nodes.
BI was performed with MrBayes v3.1.2 (Ronquist and Huelsenbeck, Sweden) [49]. Four Markov chains were run from random starting trees for 6 million generations for ITS + nLSU and for 13 million generations for ITS + nLSU + mtSSU + TFF1 + TBB1, and trees were sampled every 100th generation. The first 25% of trees were discarded as burn-in, and the remaining trees were used to calculate Bayesian posterior probabilities (BPP) of the clades.

Phylogeny
The combined ITS + nLSU dataset included sequences from 159 fungal samples representing 108 taxa. The dataset had an aligned length of 2215 characters, of which 1257 characters were constant, 235 were variable and parsimony-uninformative, and 723 were parsimony-informative. BI analysis generated topologies similar to those of ML analysis, with an average standard deviation of split frequencies at 0.004614 (BI). The topology from the ML analysis with a maximum likelihood bootstrap (BS) ≥ 50% and Bayesian posterior probabilities (BPP) ≥ 0.90 labeled on branches is shown ( Figure 1).  The combined five-gene (ITS, nLSU, mtSSU, TEF1, TBB1) sequence dataset included sequences from 119 fungal samples representing 70 taxa. The dataset had an aligned length of 3498 characters, of which 2285 characters were constant, 226 were variable and parsimony-uninformative, and 987 were parsimony-informative. BI analysis generated topologies similar to those of ML analysis, with an average standard deviation of split frequencies = 0.007253 (BI). The topology from the ML analysis with a maximum likelihood bootstrap (BS) ≥ 50% and Bayesian posterior probabilities (BPP) ≥ 0.90 labeled on branches is shown (Figure 2).   (Figures 1 and 2). Morphologically, P. cinereofusca differs from species of Perenniporia s. s. by its resupinate basidiocarps with a gray to pale brown pore surface, tissues darkening in KOH, hyaline to pale yellowish, and non-dextrinoid basidiospores. Thus, the new genus Dendroporia is set up and the new combination Dendroporia cinereofusca is proposed.
In the current phylogenetic studies, Dendroporia is related to Tropicoporia and Sparsitubus, but with only weak support, and Tropicoporia differs from Dendroporia by its buffyellow to grayish orange pore surface, non-dextrinoid skeletal hyphae, and dextrinoid basidiospores. Sparsitubus differs from Dendroporia in having effused reflexed to pileate basidiocarps and non-truncate, ornamented basidiospores [54]. For a detailed description of Perenniporia cinereofusca, see Zhao et al. [20]. Notes: Dendroporia cinereofusca was first described in Perenniporia from tropical China [20] and is characterized by its resupinate basidiocarps with gray to pale brown pore surfaces, a dimitic hyphal system with weakly dextrinoid skeletal hyphae, tissues becoming brown to black in KOH, the presence of dendrohyphidia, and hyaline to pale yellowish, truncate, and non-dextrinoid basidiospores. Differs from other genera by its resupinate basidiocarps with buff-yellow to cinnamonbuff pore surface, a dimitic hyphal system with weak to strong dextrinoid skeletal hyphae, the presence of cystidioles, and thick-walled, ellipsoid, and non-truncate, dextrinoid, and cyanophilous basidiospores.
Type species: Etymology: Luteoperenniporia (Lat.) refers to resembling Perenniporia but with a buffyellow pore surface when dry.
Basidiocarps are annual to perennial and resupinate. Pore surface iscream, buff to pale cinnamon buff when fresh, and becoming buff, buff-yellow to cinnamon-buff upon drying; pores are round to angular; dissepiments thin, entire to lacerate. Subiculum is thin and buff to cinnamon-buff. Tubes are concolorous with pore surface and corky. Hyphal system is dimitic, generative hyphae with clamp connections; skeletal hyphae weakly to strongly dextrinoid, CB+; tissues are unchanged in KOH. Cystidia is absent; cystidioles are present. Basidiospores are ellipsoid, non-truncate, hyaline, thick-walled, smooth, dextrinoid, and CB+.
Notes: In the combined ITS + nLSU and five-gene phylogenetic analyses, the species of Luteoperenniporia formed a single clade with high support (Figures 1 and 2) distant from the Perenniporia s. s. clade. Morphologically, Luteoperenniporia differs from Perenniporia s. s. by its buff, buff-yellow to cinnamon-buff pore surfaces, a dimitic hyphal system with weakly to strongly dextrinoid skeletal hyphae and non-truncate basidiospores. Therefore, three new combinations are proposed in Luteoperenniporia, and the new species is described below. For a detailed description of Perenniporia bannaensis, see Zhao et al. [19]. Notes: Luteoperenniporia bannaensis was recently described in Perenniporia from China by Zhao et al. [19]; it is closely related to L. yinggelingensis in morphology and phylogeny; they share annual and resupinate basidiocarps, cream to buff pore surface and a dimitic hyphal system with dextrinoid and cyanophilous skeletal hyphae, and both species are distributed in the tropics. However, L. yinggelingensis is distinguished from L. bannaensis by its larger pores and basidiospores (pores 5-6 per mm, basidiospores 6.2-7.5  For a detailed description of Perenniporia mopanshanensis, see Zhao and Ma [28]. Notes: Luteoperenniporia mopanshanensis was recently described in Perenniporia by Zhao and Ma [28]. L. mopanshanensis and L. bannaensis are both reported from Yunnan Province in southern China. They share resupinate basidiocarps, a dimitic hyphal system with strongly dextrinoid skeletal hyphae, non-truncate, and strongly dextrinoid and similar sized basidiospores. However, L. bannaensis differs by having an annual growth habit and smaller pores (6-8 per mm) [19]. For a detailed description of Perenniporia yinggelingensis, see Cui et al. [3]. Notes: Luteoperenniporia yinggelingensis was newly described from a tropical area of China [3]. It is characterized by annual and resupinate basidiocarps with slightly lacerate pores, a distinct sterile margin, and a dimitic hyphal system with weakly dextrinoid skeletal hyphae. Macroscopically, L. yinggelingensis is close to L. mopanshanensis, but the latter species has perennial basidiocarps, larger pores (3-5 per mm), indistinct sterile margins, and strongly dextrinoid skeletal hyphae [28]. Spores: Basidiospores are ellipsoid, non-truncate, hyaline, thick-w trinoid, CB+, (6-) 6.2-7.4 (-7.7) × (3.9-) 4-5.2 (- 5.4) µm, L = 6.77 µm, W 1.54 (n = 90/3).
Notes: Luteoperenniporia australiensis is characterized by its annu resupinate basidiocarps, buff to cinnamon-buff pore surface, entire dimitic hyphal system with dextrinoid skeletal hyphae, presence of cy soid, non-truncate, dextrinoid, and cyanophilous basidiospores. Lu naensis is similar to L. australiensis by sharing a buff-yellow to pinkish dimitic hyphal system with dextrinoid, and cyanophilous skeletal hy bannaensis differs from L. australiensis by its smaller pores (6-8 per m sidiospores (5.2-6 × 4-4.6 µm) [19]. Luteoperenniporia yinggelingensis m L. australiensis by having resupinate basidiocarps, and similar pore size However, L. yinggelingensis is distinguished from L. australiensis m growth habit and cream to buff pore surface [3]. Perenniporia subaur Cleland) P.K. Buchanan & Ryvarden is also described from Tasmania teoperenniporia australiensis in its resupinate basidiocarps, dimitic hyph trinoid and cyanophilous skeletal hyphae, and presence of cystidioles, has greyish cream to greyish orange pore surfaces and larger basidios 5.5 µm) [55] Additional          Etymology: australiensis (Lat.) refers to the country where the new species was found. Fruitbody: Basidiocarps are annual to perennial, resupinate, without odor or taste when fresh, corky to hard corky when dry, and up to 14 cm long, 8.5 cm wide, and 7 mm thick at center. Pore surface is buff-yellow, pinkish buff to pale cinnamon-buff when fresh, and buff, pale yellowish-brown to cinnamon-buff upon drying; pores are round to angular, 4-6 per mm, dissepiments thin, entire to lacerate. Sterile margin is distinct to indistinct, buff, and up to 2 mm wide. Subiculum is thin, buff, and up to 1 mm thick. Tubes are concolorous with pore surface, corky to hard corky when dry, and up to 6 mm long.
Macroporia tibetica (B.K. Cui [16]. Notes: Macrosporia nanlingensis was first described in Perenniporia from southern China [16]; it is characterized by annual and resupinate basidiocarps, a cinnamon-buff pore surface when dry, a trimitic hyphal system with slightly dextrinoid skeletal hyphae, and ellipsoid, truncate, strongly dextrinoid, and cyanophilous basidiospores that are usually longer than 9 µm. Specimens examined: CHINA. Guangdong Province, Ruyang County, Nanling Nature Reserve, on dead angiosperm tree, 16 (Figure 1), which is distinct from the Perenniporia s. s. clade and closely related to the Perenniporiella clade. Further phylogeny ( Figure 2) inferred from the combined five-gene dataset indicated that the clade of P. minor was distant from the Perenniporia s. s. clade and closely related to the Neoporia clade. However, Neoporia has resupinate basidiocarps, dextrinoid skeletal hyphae, and non-truncate basidiospores; Perenniporiella has dextrinoid skeletal hyphae and non-truncate basidiospores [30]. Perenniporia minor differs from species of Perenniporia s. s. by its annual and pileate basidiocarps with a cream to pale buff pileal surface, a dimitic hyphal system with weakly amyloid skeletal hyphae. Therefore, Minoporus gen. nov [11]. Notes: This species was described from northeastern China by Xiong et al. [11] and is characterized by annual and pileate basidiocarps, cream to pale buff when fresh and cinnamon buff when dry pileal surface, a dimitic hyphal system with weakly amyloid skeletal hyphae, and ellipsoid, truncate, dextrinoid, and cyanophilous basidiospores. Basidiocarps are annual, resupinate and corky when dry. Pore surface is cream to buff when fresh, buff-yellow to grayish orange upon drying; pores are round to angular. Subiculum is cream to buff. Tubes are concolorous with the pore surface and corky. Hyphal system is dimitic; generative hyphae with clamp connections; skeletal hyphae dextrinoid, CB+; tissues unchanged in KOH. Basidiospores are ellipsoid, non-truncate, hyaline, thickwalled, smooth, dextrinoid, and CB+.
Notes: In our phylogenetic analyses, three species previously included in Perenniporia, P. bostonensis C.L. Zhao Morphologically, this clade differs from Perenniporia s. s. by its dimitic hyphal system and non-truncate basidiospores. Therefore, Neoporia gen. nov. is proposed to accommodate P. bostonensis, P. koreana and P. rhizomorpha.
Neoporia rhizomorpha (B.K. Cui  For a detailed description of Perenniporia decurrata, see Corner [52]. Notes: Perenniporia decurrata was first described from Malaysia [52]. Perenniporia chiangraiensis was recently described from Northern Thailand based on morphological characters and molecular data by Ji et al. [25]. However, these authors overlooked P. decurrata, which is a priority name for this species. The species is characterized by pileate basidiocarps with concentrically sulcate pileal surfaces, white pore surfaces, the presence of dendrohyphidia and cystidioles, and ellipsoid, truncate, thick-walled, and non-dextrinoid basidiospores. Specimens For a detailed description of Perenniporia russeimarginata, see Zhao and Cui [17]. Notes: Niveoporia russeimarginata was first described in Perenniporia from southern China [17]. Perenniporia alboferruginea Decock, described from Cameroon in Africa, is similar to N. russeimarginata in having resupinate basidiocarps with ferruginous red upper margins and a dimitic hyphal system. However, P. alboferruginea differs by having an annual growth habit, larger pores (5-6 per mm), the absence of cystidioles, and non-dextrinoid basidiospores [57]. brown, and up to 2 mm wide. Subiculum is buff, thin, up to 0.5 mm th woody hard when dry, and up to 11.5 mm long. Hyphal structure: Hyphal system is dimitic; generative hyphae nections; skeletal hyphae is weakly dextrinoid and CB+; tissues are un Subiculum: Generative hyphae are infrequent, hyaline, thin-walle 1-2.2 µm in diameter; skeletal hyphae are dominant, hyaline, thick-w branched, interwoven, and 1-2.5 µm in diameter.
Spores: Basidiospores are broadly ellipsoid, truncate or not, hy smooth, weakly dextrinoid, CB+, (4-)4.       Basidiocarps are annual to perennial and resupinate. Pore surface is white to cream when fresh, cream to buff when dry; pores are round and small. Subiculum is thin, cream, and corky. Tubes are concolorous with pore surface and corky. Hyphal system is dimitic to trimitic; generative hyphae with clamp connections; skeletal hyphae are non-dextrinoid to dextrinoid or amyloid, cyanophilous; tissues are unchanged in KOH. Cystidia are absent, cystidioles are present. Basidiospores are ellipsoid, truncate, hyaline, thick-walled, smooth, dextrinoid, and CB+.
Fruitbody: Basidiocarps are perennial, resupinate, sometimes pileate, corky, without odor or taste when fresh, becoming woody hard upon drying. Pilei are irregular, projecting up to 2 cm, 5 cm wide, and 3 cm thick at the base; with resupinate up to 9 cm long, 5 cm wide, and 1.3 cm thick at center. Pileal surface is orange-brown to reddish brown when fresh, umber brown when dry, glabrous, and concentrically sulcate. The pore surface is white when fresh, cream upon drying; pores are round to angular, 5-6 per mm, dissepiments thick, entire. Sterile margin is distinct to indistinct, cinnamon to rusty reddish brown, and up to 2 mm wide. Subiculum is buff, thin, up to 0.5 mm thick. Tubes are buff, woody hard when dry, and up to 11.5 mm long.
Hyphal structure: Hyphal system is dimitic; generative hyphae bearing clamp connections; skeletal hyphae is weakly dextrinoid and CB+; tissues are unchanged in KOH.
Additional    Basidiocarps are annual to perennial and resupinate. Pore surface is white to cream when fresh, cream to buff when dry; pores are round and small. Subiculum is thin, cream, and corky. Tubes are concolorous with pore surface and corky. Hyphal system is dimitic to trimitic; generative hyphae with clamp connections; skeletal hyphae are non-dextrinoid to dextrinoid or amyloid, cyanophilous; tissues are unchanged in KOH. Cystidia are absent, cystidioles are present. Basidiospores are ellipsoid, truncate, hyaline, thick-walled, smooth, dextrinoid, and CB+.
Notes: In our phylogenetic analyses, the species of Perenniporia s. l. clustered into several clades, Perenniporia medulla-panis is grouped with P. substraminea B.K. Cui  Basidiocarps are annual to perennial, resupinate to effused-reflexed, and corky when dry. Pore surface is dingy yellowish, cinnamon to ochraceous; pores are round to angular. Context is thin, cream, buff to pale ochraceous. Tubes are concolorous with pore surface, corky. Hyphal system is dimitic to trimitic; generative hyphae with clamp connections; skeletal hyphae is unbranched, strongly dextrinoid, and cyanophilous. Basidiospores are ellipsoid to subglobose, non-truncate, hyaline, thick-walled, smooth, non-dextrinoid to dextrinoid, and CB+.
Basidiocarps are annual to perennial, resupinate, and corky when dry. Rhizomorphs are present. Pore surface is grayish white to pale buff when dry; pores are round; dissepiments thick, entire. Subiculum is thin, cream. Tubes are concolorous with pore surface and corky. Hyphal system is dimitic; generative hyphae with clamp connections; skeletal hyphae are dextrinoid and CB+; tissues are unchanged in KOH. Cystidia are absent; cystidioles are present. Basidiospores are ellipsoid, truncate, hyaline, thick-walled, smooth, dextrinoid, and CB+.
Hornodermoporus was established by Teixeira [73] and typified by H. martius (Berk.) Teixeira. The genus is characterized by its pileate basidiocarps with a black crust at the pileal surface, a dimitic hyphal system with strongly dextrinoid and cyanophilous skeletal hyphae, the presence of cystidia, truncate, oblong-ellipsoid, and strongly dextrinoid basidiospores.
According to phylogenetic analyses and morphological characters, some species of Perenniporia s. l. have a new generic placement. For four species in the phylogenetic tree, including Perenniporia tephropora (Mont.) Ryvarden, P. subtephropora B.K. Cui & C.L. Zhao, P. eugeissonae P. Du & Chao G. Wang and P. straminea (Bres.) Ryvarden, due to unclear phylogenetic relationships and insufficient morphological difference from Perenniporia s. s. species, their taxonomic positions were remained in Perenniporia s. l.
In summary, we carried out a comprehensive study on Perenniporia s. l., 44 species of Perenniporia s. l. with available sequences. According to phylogenetic evidence and morphological characteristics, 15 new genera were set up, 2 new species were described, and 37 new combinations were proposed. Species lacking reliable molecular sequences were not included in this study.