We describe the morpho-anatomical features of the ectomycorrhizas (ECMs) formed by Lactifluus rugatus on Cistus, a genus of about 20 species of woody shrubs typical of the Mediterranean maquis. The description of L. rugatus mycorrhizas on Cistus is the first ECM description of a species belonging to Lactifluus subgen. Pseudogymnocarpi. The ECM identity was verified through molecular tools. Anatomically, the characteristic of L. rugatus mycorrhiza is the presence of abundant, long "bottle-shaped" cystidia on mantle surface. Indeed, the overwhelming majority of milkcap mycorrhizas are acystidiate. This is the third Lactarius/Lactifluus mycorrhiza to have been described associated with Cistus, the others being Lactarius cistophilus and L. tesquorum. The phylogenetic distance between all these taxa is reflected by the diversity of the principal features of their ECMs, which share host-depending ECM features known for Cistus, but are otherwise distinguishable on the host roots. Comparison of Lactifluus rugatus ECM with those formed by L. vellereus and L. piperatus on Fagus reveals elevated intrageneric diversity of mycorrhizal structures. Such a diversity is supported by analysis of ITS sequences of relevant species within European Lactifluus species. Our study extends knowledge of Cistus mycorrhizal biology and confirms the informative value of mycorrhizal structures in understanding phylogenetic relationships in ECM fungi.

中文翻译：

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窥视地中海黑匣子：岩蔷薇上的乳杆菌外生菌根。


我们描述了岩蔷薇 (Cistus) 上的乳杆菌 (Lactifluus rugatus) 形成的外生菌根 (ECM) 的形态解剖学特征，岩蔷薇属约 20 种典型的地中海马基灌木木本灌木。对岩蔷薇上 L. rugatus 菌根的描述是对 Lactifluus 亚属物种的第一个 ECM 描述。假裸果属。 ECM 身份通过分子工具验证。解剖学上，L. rugatus 菌根的特征是在地幔表面存在丰富的、长的“瓶状”孢囊。事实上，绝大多数乳帽菌根都是酰基菌根。这是第三种与岩蔷薇相关的 Lactarius/Lactifluus 菌根，另外两个是 Lactarius cistophilus 和 L. tesquorum。所有这些类群之间的系统发育距离反映在其 ECM 主要特征的多样性上，这些特征具有岩蔷薇已知的依赖于宿主的 ECM 特征，但在宿主根部上是可区分的。将 Lactifluus rugatus ECM 与水青冈上的 L. vellereus 和 L. Piperatus 形成的 ECM 进行比较，发现菌根结构的属内多样性有所提高。对欧洲乳杆菌属相关物种的 ITS 序列的分析支持了这种多样性。我们的研究扩展了岩蔷薇菌根生物学知识，并证实了菌根结构在理解 ECM 真菌系统发育关系方面的信息价值。