Clitocella colorata L. Fan & N. Mao, 2022

Mao, Ning, Lv, Jing-Chong, Xu, Yu-Yan, Zhao, Tao-Yu & Fan, Li, 2022, Two new Clitocella species from North China revealed by phylogenetic analyses and morphological characters, MycoKeys 88, pp. 151-170 : 151

Clitocella colorata L. Fan & N. Mao sp. nov.

Figs 3b-d , 5 , 6c, d

Etymology.

colorata, referring to the colorful pileus.

Holotype.

China. Shanxi Province, Pu County, Wulushan Mountain, 36°33.2'N, 111°11.58'E, alt. 1740 m, 28 July 2021, on the ground in coniferous forest dominated by Pinus armandii Franch., N. Mao MNM292 (BJTC FM1891).

Diagnosis.

Clitocella colorata is characterized by its clitocyboid basidiomata, relatively colorful pileus (white to yellowish white, grayish white to grayish brown, pink white), globose or subglobose to broadly ellipsoid basidiospores, hyphae of pileipellis with pale yellow to yellowish brown intracellular or parietal pigment, the absence of hymenial cystidia and clamp connection. It is most similar to C. popinalis and C. mundula but differs from C. popinalis by its slightly smaller basidiospores, only appearing in the forest and genetic profile, and from C. mundula by its colorful pileus (white to yellowish white, grayish white to grayish brown, pink white).

Description.

Basidiomata clitocyboid, small to large. Pileus 20-62 mm wide, dry,convex to plano-convex, sometimes infundibuliform, with a shallow depression at the center; margin not striate, often enrolled or flat, sometimes slightly uplifted; surface white (#ffffff) to yellowish white (#ffffe7), grayish white (#f2f2f2) to grayish brown (#dba773), pink white (#fff3f5); context white (#ffffff) to grayish white (#f2f2f2), 1.0-1.5 mm thick. Lamellae decurrent, white (#ffffff) to yellowish white(#fff3e7), becoming yellowish brown (#e0b487) on drying, crowded, 1.0-2.0 mm deep, edges entire and concolorous, thin and fragile, lamellulae in 2-4 tiers of varying lengths. Stipe 22-42 × 4-10 mm, central, cylindrical, equal, pale white (#ffffff) to yellowish brown (#e0b487), smooth, usually with white rhizomorphs. Odor unrecorded. Taste not recorded. Chemical color reaction: pileal surface of dried samples negative with 3% KOH.

Basidiospores [100/5/2] (3.8-)4.5-5.5(-6.0) × (3.5-)4-4.8(-5.0) μm; Lm × Wm = 4.90 ( ± 0.44) × 4.29 ( ± 0.35), Q = 1.00-1.25 (Qav = 1.14 ± 0.09); hyaline, globose or subglobose to broadly ellipsoid in profile view, slightly angled in polar or face view with obscure minute pustules or bumps. Basidia 20-30 × (4.5-)5-6.5 μm, clavate, hyaline, with four spored, rarely two spored; sterigmata 2-3.5 μm long. Lamellar trama composed of subparallel, hyaline, cylindrical hyphae, 2.5-6 μm wide, subhymenium consisting of filamentous hyphal segments, 2-3.5 μm wide. Lamellae edges fertile. Pleurocystidia and cheilocystidia absent. Pileipellis a cutis composed of parallel, compactly arranged, non-gelatinized, smooth, cylindrical hyphae, 2-5 μm wide, with pale yellow to yellowish brown intracellular or parietal pigment; subcutis made up of interwoven, slightly loosely arranged, hyaline, smooth, cylindrical hyphae, 3-6.5 μm wide; pileal trama composed of parallel, compactly arranged, hyaline, cylindrical hyphae, 3-10 μm wide. Stipitipellis a cutis composed of parallel, compactly arranged, thin-walled, non-gelatinized, cylindrical hyphae, 2-5 μm wide, heavily or moderately encrusted with brown pigment. Stipititrama composed of parallel, compactly arranged, hyaline, cylindrical hyphae, 3-7 μm wide. Caulocystidia absent. Clamp connections absent.

Habit.

Scattered or in groups on soil or rotten wood in coniferous ( Pinus ) or broad-leaved ( Quercus ) forest, Shanxi province, China.

Additional specimens examined.

China. Shanxi province, Pu County, Wulushan Mountains, alt. 1750m, 28 July 2021, N. Mao MNM293 (BJTC FM1892); Wenshui County , alt. 1760m, 30 July 2021, L. Fan CF1219 (BJTC FM1952); Xia County , alt. 931m, 6 October 2020, N. Mao MNM102 (BJTC FM1593); Xia County , alt. 931m, 6 October 2020, N. Mao MNM103 (BJTC FM1594) .

Notes.

Morphologically, Clitocella colorata is easily confused with C. mundula and C. popinalis . However, according to Baroni (1981; as Rhodocybe ), the pileus surface in C. mundula and C. popinalis can produce a reddish reaction in 3% KOH, whereas that is not exhibited in Clitocella colorata . The basidiospores of C. popinalis , 5.5-7 × 5-5.5 μm ( Baroni 1981; Kluting et al. 2014; Jian et al. 2020), are broader and longer than those of C. colorata (4.5-5.5 × 4-4.8 μm). DNA analysis revealed that C. colorata shared less than 87.80% similarity in tef1 sequence with C. mundula and 86.10% similarity with C. popinalis , supporting their separation. Moreover, five ITS sequences (FJ770397, KR673647, KU561066, MK217434 and MK573922) labelled " C. popinalis " from India, Norway, South Korea, UK and USA are probably conspecific to the new species C. colorata as they clustered together with C. colorata in ITS tree (Fig. 2 ) and have more than 98.4% similarity in ITS region. However, these " C. popinalis " collections still need more other DNA regions and detailed morphology to support this view. One collection of " C. mundula ," namely, AFTOLID 521 from Norway, should be re-identified C. colorata as it clustered together with C. colorata in the combined nrLSU- rpb2 - tef1 - atp6 tree (Fig. 1 ) and have more than 98.1% similarity in tef1 region. These showed that the new species C. colorata maybe have a wide geographical distribution. Although C. orientalis is sister to C. colorata with strong support, these two species have obvious differences in morphology. The pileus and stipe of C. orientalis are usually viscid when wet and have gelatinized pileipellis and stipitipellis. Clitocella colorata has non-gelatinized pileipellis and stipitipellis, and its pileus is more colorful and darker ( Jian et al. 2020). DNA analysis revealed that C. colorata shared less than 95.80% similarity in tef1 sequence with C. orientalis and 90.20% similarity in ITS sequence. Moreover, C. colorata has a wider distribution range than C. orientalis , which is only distributed in China.

Figures

Figure 1. Phylogeny derived from Maximum Likelihood analysis of the combined nrLSU- rpb 2 - tef 1 - atp 6 dataset of Clitocella and related genera in the family Entolomataceae. Clitopilopsis albida was employed to root the tree as an outgroup. Numbers representing likelihood bootstrap support (BS ≥ 70 %, left) and significant Bayesian posterior probability (BPP ≥ 0.95, right) are indicated above the nodes. New sequences are highlighted in bold.

Figure 2. Phylogeny derived from Maximum Likelihood analysis of the ITS sequences from Clitocella and related genera in the family Entolomataceae. Mycena pura was employed to root the tree as an outgroup. Numbers representing likelihood bootstrap support (BS ≥ 70 %, left) and significant Bayesian posterior probability (BPP ≥ 0.95, right) are indicated above the nodes. New sequences are highlighted in bold.

Figure 3. Basidiomata of Clitocella a Clitocella borealichinensis (BJTC FM 1781, holotype) b-d Clitocella colorata (b BJTC FM 1593 c BJTC FM 1952 d BJTC FM 1891, holotype) Scale bars: 10 mm (a-d). Photos by JingZhong Cao

Figure 5. Microscopy of Clitocella colorata a basidiospores b basidia c pileipellis. Scale bars: 10 μm (a, c); 5 μm (b). Drawings by Ning Mao.

Figure 6. Basidiospores of species in Clitocella. Clitocella revealed by SEM a, b Clitocella borealichinensis c, d Clitocella colorata Scale bars: 3 μm (a, b); 5 μm (c, d). Photos by Li Fan.