Key Laboratory for Forest Resources Conservation and Utilization in the Southwest Mountains of China, Ministry of Education, Southwest Forestry University, Kunming, P. R. China.
College of Biodiversity Conservation, Southwest Forestry University, Kunming, P. R. China.
PLoS One. 2021 Jan 13;16(1):e0244520. doi: 10.1371/journal.pone.0244520. eCollection 2021.
Two new wood-inhabiting fungal species, Steccherinum tenuissimum and S. xanthum spp. nov. are described based on a combination of morphological features and molecular evidence. Steccherinum tenuissimum is characterized by an annual growth habit, resupinate basidiomata with an odontioid hymenial surface, a dimitic hyphal system with clamped generative hyphae, strongly encrusted cystidia and basidiospores measuring 3-5 × 2-3.5 μm. Steccherinum xanthum is characterized by odontioid basidiomata and a monomitic hyphal system with generative hyphae bearing clamp connections and covering by crystals, colourless, thin-walled, smooth, IKI-, CB-and has basidiospores measuring 2.7-5.5 × 1.8-4.0 μm. Sequences of the ITS and nLSU nrRNA gene regions of the studied samples were generated, and phylogenetic analyses were performed with maximum likelihood, maximum parsimony and Bayesian inference methods. The phylogenetic analyses based on molecular data of ITS + nLSU sequences showed that two new Steccherinum species felled into the residual polyporoid clade. Further investigation was obtained for more representative taxa in Steccherinum based on ITS + nLSU sequences, which demonstrated that S. tenuissimum and S. xanthum were sister to S. robustius with high support (100% BP, 100% BS and 1.00 BPP).
两种新的木生真菌物种，Steccherinum tenuissimum 和 S. xanthum spp. nov.，是基于形态特征和分子证据的组合而描述的。Steccherinum tenuissimum 的特征是一年生生长习性、反卷的担子果具有齿状的子实层表面、二歧式的菌丝系统，具夹生的生殖菌丝、强烈矿化的囊状体和 3-5×2-3.5μm 的担孢子。Steccherinum xanthum 的特征是齿状的担子果和单歧式的菌丝系统，生殖菌丝具夹生连接并被晶体覆盖，无色、薄壁、光滑、不染色、CB-和 2.7-5.5×1.8-4.0μm 的担孢子。对研究样本的 ITS 和 nLSU nrRNA 基因区域的序列进行了生成，并通过最大似然法、最大简约法和贝叶斯推断法进行了系统发育分析。基于 ITS+nLSU 序列的分子数据分析的系统发育分析表明，两种新的 Steccherinum 物种归入残余多孔菌类群。进一步的研究是基于 ITS+nLSU 序列对 Steccherinum 中的更多代表性类群进行的，结果表明 S. tenuissimum 和 S. xanthum 与 S. robustius 具有高度支持（100%BP、100%BS 和 1.00BPP），是姊妹关系。
