Two new species of Nectriaceae (Hypocreales, Sordariomycetes) from Yunnan, China

Abstract

Nectriaceae is a highly diverse family, and members have a worldwide distribution, particularly in warm temperate to tropical regions. During the survey of fungal diversity in different habitats in Yunnan province, China, two new species isolated from soil and air respectively, namely Atractiumyunnanense sp. nov. and Nalanthamalaxishuangbannaensis sp. nov., were proposed based on morphological comparisons and the multi-gene phylogenetic analyses of combined ITS, LSU, rpb2, and tub2 sequence data. Phylogenetically, both species clustered in a monophyletic clade within Nectriaceae with strong support. A.yunnanense is characterized by synnematous conidiophores, pale olivaceous-green, clavate to oblong-ellipsoidal, multi-septate conidia, and pale olivaceous-green chlamydospores. N.xishuangbannaensis has acremonium-like or penicillium-like conidiophores and either obovate or ellipsoidal, cylindrical or fusiform conidia. Full descriptions, illustrations, and a phylogenetic tree showing the phylogenetic position of the two new species were provided.

Keywords: Air-borne or soil-borne fungi; Hypocreales; fungal diversity; phylogeny; taxonomy.

Figure 1.

Phylogenetic tree inferred from a Maximum likelihood analysis based on a concatenated alignment of ITS, LSU, rpb2 and tub2 sequences of some representing species in Nectriaceae. The Bayesian posterior probabilities (BP) ≥ 0.9 and RAxML bootstrap support values (BS) ≥ 75% were shown at the nodes (BP/BS). Strains obtained in this study are shown in blue font. Ex-type strains are marked by a ^T after the strain number. The tree was rooted to Sarocladiumsummerbellii (CBS 430.70).

Figure 2.

Atractiumyunnanense (YMF 1.06524, holotype) A colony on PDA after 14 days of inoculation at 28 °C B colony on CMA after 3 days of inoculation at 28 °C C conidiophores D conidia E chlamydospores. Scale bars: 1.9 cm (A, B); 10 µm (C–E).

Figure 3.

Nalanthamalaxishuangbannaensis (YMF 1.05062, holotype) A colony on PDA after 3 days of inoculation at 28 °C B colony on CMA after 3 days of inoculation at 28 °C C conidia arranged in long chains under low power microscopy D, E acremonium-like conidiophores F–H penicillate conidiophores I conidia. Scale bars: 1.0 cm (A, B); 50 µm (C); 10 µm (D–I).