Alloclavaria orientalis P.T. Deng & P. Zhang, 2023

Deng, Peng-Tao, Yan, Jun, Liu, Xiang-Fen & Zhang, Ping, 2023, An unexpected discovery of a new species in Alloclavaria (Rickenellaceae, Hymenochaetales) from China, Phytotaxa 625 (1), pp. 108-115 : 110-111

Alloclavaria orientalis P.T. Deng & P. Zhang , sp. nov.

( Figs. 1 , 2 )

MycoBank:849849

Diagnosis:—Differs from Alloclavaria purpurea by having shorter basidiospores and broader cystidia, as well as unique molecular sequence data.

Holotype:— CHINA. Hunan Province, Rucheng County, 25°55′60″N, 113°69′15″E, alt. 700m, 13 April 2023, leg. P. Zhang ( MHHNU11416 ).

Etymology:—orientalis (eastern), refers to the occurrence of the species in East Asia.

Description:— Basidiomata simple, fragile, cylindric, caespitose, gregarious solitary, sometimes caespitoseconnate at the base, 3–10 cm tall, 2–5mm broad. Fertile part clavate or sub-cylindric, sometimes fusiform and slightly flexuous, dull purple [15A8–C8, purple, true purple] or purplish lilac, sometimes pinkish buff [14A4–A8, purplish pink, purplish red], discolored to slightly ochraceous [4C8, deep yellow] or pale brownish, drying pale grayish and brownish purple. Apices obtuse, turning deep grayish purple [14D2–3, purplish gray] with age, sometimes shrinking and turning black. Base slender, acute, densely white villous. Sterile stipe indistinct, sometimes conspicuously twisted, longitudinally sulcate with age. Flesh fragile, hollow, hymenium concolorous. Odor not obvious, taste and macrochemical reactions not recorded.

Basidiospores [60/3/2] (6.0–)6.5–8.0(–8.5) × (3.5–)4.0–5.0(–5.5) μm [Q = 1.5–2.0(–2.12), Qm = 1.71 ± 0.18], thin-walled, hyaline in KOH, smooth, ellipsoid or oblong, inamyloid, slightly flattened, with inconspicuous apiculus, apiculus 0.3–0.5 μm long. Hyphae of the context cylindrical, parallel, hyaline, sometimes inflated to 12 μm wide, no calcium oxalate crystals, without secondary septa, clamps absent. Hyphae near subhymenium 3.0–5.0 μm wide; hyphae distant from subhymenium 7.0–9.0 μm wide. Basidia 30–40 × 4–6(6.5), (2–)4–sterigmata; sterigmata 4–6 µm long, subcylindrical, tapering from apex to base, hyaline, contents somewhat oleiferous; clamp connections absent. Cystidia present, abundant in hymenium, thin-walled, 70–90 µm long, 8–12 µm wide, clavate, slightly tapered downward.

Habit and distribution:—Caespitose to gregarious, growing on the ground among moss, generally under coniferous trees; basidiomata generally occur in spring. Known from the type region in southern China.

Additional materials examined:— CHINA. Hunan Province, Ningyuan County, under conifers, 25°84′25″N, 112°06′44″E, elev. 276 m, 05 April 2022, MHHNU10934 , MHHNU10928 ; Hunan Province, Yuanling County, under conifers, 28°75′89″N, 110°43′78″E, elev. 350 m, 31 May 2022, MHHNU11065 ; Guangxi Province, Guanyang County , under conifers, 25°45′70″N, 111°13′06″E, elev. 250 m, 12 April 2023, MHHNU11414 ; Fujian Province, Ninghua County, under conifers, 26°20′38″N, 116°49′41″E, elev. 300m, 13 April 2023, MHHNU11419 .

Phylogenetic analyses

In total, 44 sequences (22 ITS and 22 LSU) were assembled into a multi-gene dataset for the molecular phylogenetic analysis, of which 12 sequences (six ITS and six LSU) were newly generated in the present study. The combined ITS + LSU dataset consisted of 1582 aligned positions. Loreleia marchantiae (Singer and Clémençon) Redhead, Moncalvo, Vilgalys & Lutzoni (2002: 162) was selected as the outgroup ( Zhang et al. 2018). The BI phylogeny (not shown) was almost identical in topology to the ML tree, and the statistical support values showed minimal discrepancies. The phylogenetic reconstruction based on the concatenated ITS+LSU dataset ( Fig. 3 ) resolved samples of the newly discovered species, A. orientalis , as monophyletic (PP 1, BS 100 %) and most closely related to A. purpurea . In addition, two uncultured ectomycorrhizal fungus sequences clustered with A. orientalis (PP 1, BS 100 %). The representatives of other genera of Rickenellaceae formed a clade sister to Alloclavaria , of which the monophyly of Globulicium (PP 1, BS 100 %), Cotylidia (PP 1, BS 99 %), Peniophorella (PP 1, BS 100 %), Rickenella (PP 1, BS 99 %) and Resinicium (PP 1, BS 100 %) was well-supported.

Figures

FIGURE 1. Basidiomata of Alloclavaria orientalis (a MHHNU11416, b MHHNU11419). Bars = 1cm. Photos by P. Zhang.

FIGURE 2. Microscopic features of Alloclavaria orientalis (MHHNU11416). a Basidiospores. b Basidia. c Cystidia. Drawings by P.T. Deng.

FIGURE 3. Phylogenetic relationships of Alloclavaria and related genera based on the ITS + LSU sequence dataset generated by RAxML. Bayesian posterior probabilities (PP)> 0.95 and bootstrap values (BS)> 50 % are reported at the nodes (PP/BS); “–” indicates that the support value was less than the respective threshold. The newly described species is highlighted in bold.