Three new ascomycetous fungi from freshwater habitats in China

During a survey of saprobic fungi in Jiangxi and Zhejiang Province, China, three fungal species were collected from decaying wood samples in freshwater habitats. We selected the internal transcribed spacers (ITS1-5.8S-ITS2), large subunit (28S), small subunit (18S), translation elongation factor-1 alpha (<i>tef1</i>), RNA polymerase Ⅰ subunit (<i>rpb1</i>) genes and RNA polymerase II subunit (<i>rpb2</i>) genes for phylogenetic analyses. Maximum likelihood and Bayesian analyses were performed to clarify the phylogenetic affinities of the species. These species are separated from the other species in respective genera based on dimensions in ascomata, asci, ascospores and DNA sequence data. Newly added species are compared with other similar species, and comprehensive descriptions and micrographs are provided.

本研究在针对中国江西省与浙江省的腐生真菌（saprobic fungi）开展野外调查期间，于淡水生境的腐朽木材样本上采集到3个真菌物种。本研究选取内部转录间隔区（ITS1-5.8S-ITS2）、大亚基（28S rRNA基因）、小亚基（18S rRNA基因）、翻译延伸因子1α（tef1）、RNA聚合酶Ⅰ亚基（rpb1）基因以及RNA聚合酶Ⅱ亚基（rpb2）基因作为分子标记开展系统发育分析。通过最大似然法与贝叶斯推断法对这3个物种的系统发育亲缘关系进行解析与澄清。基于子囊果、子囊、子囊孢子的形态量度特征与DNA序列数据，这3个物种可与各自属内的其他物种明确区分。本研究将本次新增的3个物种与近缘相似物种开展比对，并提供了详尽的形态描述与显微图像资料。