Nemania rubi Y.H. Pi & Q.R. Li, 2021

Pi, Yin Hui, Long, Si Han, Wu, You Peng, Liu, Li Li, Lin, Yan, Long, Qing De, Kang, Ji Chuan, Kang, Ying Qian, Chang, Chu Rui, Shen, Xiang Chun, Wijayawardene, Nalin N., Zhang, Xu & Li, Qi Rui, 2021, A taxonomic study of Nemania from China, with six new species, MycoKeys 83, pp. 39-67 : 39

Nemania rubi Y.H. Pi & Q.R. Li sp. nov.

Fig. 9

Etymology.

Refers to the name of host genus, rubus.

Material examined.

China, Guizhou Province, Pingba County (26°25'13.38"N, 106°24'25.23"E, altitude: 1255 m), on dead branches of Rubus lambertianus Ser., 5 September 2020, Y.H. Pi, 2020PB70 (GMB0064, holotype; GMBC0064, ex-type living culture; KUN-HKAS 112695, isotype) .

Description.

Saprobic on dead branches of R. lambertianus . Sexual morph: Stromata effused-pulvinate, irregular shape, multi-peritheciate, scattered, separate to confluent into larger compound stromata, 2.5-15 mm long × 2-9 mm wide × 0.4-0.6 mm thick; surface blackish, weakly carbonaceous, with unexposed perithecial contours, uneven and irregular, internally whitish between ascomata, tissue, soft-textured; not releasing a coloured pigment in 10% KOH. Perithecia 0.25-0.35 mm diam. × 0.2-0.3 mm high, subglobose. Ostioles papillate, black, obtusely conical to hemispherical, without encircling disc. Asci 85-160 × 7-11 μm (av. = 130 × 9 μm, n = 30), 8-spored, unitunicate, cylindrical, long-stipitate, spore-bearing parts 60-85 µm long, apically rounded with a J+, long-cylindrical apical apparatus, 1.5-2.5 × 2-3 µm (av. = 1.5 × 2.5 µm, n = 30). Ascospores 9-12 × 4-6 μm (av. = 10 × 4.8 μm, n = 30), uniseriate to irregularly-biseriate unicellular, smooth, olivaceous when fresh, turning brown to medium brown after a period of time, ellipsoid-inequilateral with often broadly-rounded ends, lacking a germ slit sheath and appendage; perispore indehiscent in 10% KOH. Asexual morph: Undetermined.

Culture characteristics.

Colonies grow slowly on PDA medium with a diameter of 5 cm after 10 days at 25 °C. Colonies surface were white to pale orange, circular, cottony, low, dense, cottony mycelium, reverse with light orange mycelium. Not sporulating on OA nor on PDA.

Other examined material.

China, Guizhou Province, Pingba County (26°25'10.24"N, 106°24'25.21"E, altitude: 1052 m), on dead wood, 5 September 2020, Y.H. Pi, 2020PB22 (GMB0063), living culture, GMBC0063 .

Notes.

In our phylogenetic analysis, Nemania rubi formed a distinct branch, which is sister to N. changningensis and N. caries (Fig. 1 ). In morphology, N. rubi is similar to N. caries , but is distinct in having a long-cylindrical apical apparatus and the inequilateral ascospores lacking a germ slit ( Miller 1961; Ju and Rogers 2002). In addition, the perithecia of N. caries are obovoid (0.3-0.6 × 0.5-0.7 mm) and its height is greater than the width ( Tang et al. 2007). The ascomata surface of N. rubi ascomata is uneven with inconspicuous perithecial mounds, which is similar to those of N. plumbea , but the latter has larger ascospores (13-16 × 5.4-6.6 µm) with germ slits on the concave side ( Tang et al. 2007).

Figures

Figure 1. RAxML tree based on analysis of a combined dataset of ITS, α-actin, rpb 2 and β-tubulin sequences from taxa of Nemania and related genera. Bayesian posterior probability (PP) ≥ 0.90 is marked at the node and the maximum likelihood bootstrap support (BS) values greater than ≥ 75 %; a dash (" - ") indicates a value <0.90 (PP) or <75 % (BS). The strain number is indicated after the species name. The here-studied strains are in bold and new species are indicated in red.

Figure 9. Nemania rubi (GMB 0064, holotype) A type material B, C stromata on surface of host D transverse sections of stromata E longitudinal section of stromata F-H asci with ascospores I pigments in 10 % KOH J ascospore with indehiscent perispore in 10 % KOH K ascus apical apparatus (stained in Melzer's Reagent) L, M ascospores N, O colonies on PDA (N - upper, O - lower). Scale bars: 0.5 mm (C-E); 10 μm (F-H, J-M).