Rare but widespread: A systematic revision of the truffle-forming genera <i>Destuntzia</i> and <i>Kjeldsenia</i> and the formation of a new genus, <i>Hosakaea</i>

Here we present the results of taxonomic and systematic study of the rare truffle-forming genera <i>Destuntzia</i> and <i>Kjeldsenia</i>. Truffle-forming fungi are difficult to study due to their reduced morphological features and their cryptic, hypogeous fruiting habits. The rare occurrence of <i>Destuntzia</i> and <i>Kjeldsenia</i> further compounds these difficulties due to the lack of adequate material for study. Recent forays in North Carolina and Tennessee recovered new specimens of another rarely collected fungus, <i>Octaviania purpurea</i>. Morphological and phylogenetic analysis revealed that <i>Octaviania purpurea</i> is a member of the genus <i>Destuntzia</i>, and this led us to reevaluate the taxonomic status and systematic relationships of other <i>Destuntzia</i> species. We performed a multilocus phylogenetic analysis of <i>Destuntzia</i> specimens deposited in public fungaria, including all available type material, and environmental sequences from animal scat and soil. Our analyses indicate that <i>Destuntzia</i> is a member of the family Claustulaceae within the order Phallales and is a close relative of <i>Kjeldsenia</i>. Results of our phylogenetic analysis infer that three species originally described in the genus <i>Destuntzia</i> are members of the genus <i>Kjeldsenia</i>. We propose three new combinations in <i>Kjeldsenia</i> to accommodate these species as well as a new combination in <i>Destuntzia</i> to accommodate <i>Octaviania purpurea</i>. We also describe a new genus in Claustulaceae, <i>Hosakaea</i>, to accommodate a closely affiliated species, <i>Octaviania violascens</i>. Finally, we transfer the genus <i>Destunzia</i> into the family Claustulaceae and emend the description of the family. The newly proposed combinations in <i>Destuntzia</i> and <i>Kjeldsenia</i> significantly expand the known geographic ranges of both genera. The data from metabarcode analysis of scat and soil also reveal several additional undescribed species that expand these ranges well beyond those suggested by basidiomata collections. Systematic placement of <i>Destuntzia</i> in the saprotrophic order Phallales suggests that this genus is not ectomycorrhizal, and the ecological implications of this systematic revision are discussed.本研究报道了珍稀产块菌属德斯通茨亚属（*Destuntzia*）与凯尔森属（*Kjeldsenia*）的分类学与系统学研究结果。产块菌真菌因形态特征简化、子实体隐蔽且地下生长的习性，研究难度极大；而德斯通茨亚属与凯尔森属的稀有性进一步加剧了研究困境，因缺乏充足的研究材料。近期在北卡罗来纳州与田纳西州的野外调查中，我们采集到另一种罕见真菌紫色奥氏块菌（*Octaviania purpurea*）的新标本。通过形态学与系统发育分析发现，紫色奥氏块菌实为德斯通茨亚属的成员，这促使我们重新评估德斯通茨亚属其他物种的分类地位与系统发育关系。我们对保存在公共标本馆中的德斯通茨亚属标本开展了多位点系统发育分析，涵盖所有可用的模式材料，以及来自动物粪便与土壤的环境序列。分析结果显示，德斯通茨亚属隶属于鬼笔目（*Phallales*）被包菌科（*Claustulaceae*），且与凯尔森属亲缘关系密切。系统发育分析结果表明，原描述于德斯通茨亚属的3个物种实为凯尔森属的成员。我们据此在凯尔森属中发表3个新组合以容纳这些物种，并为紫色奥氏块菌发表德斯通茨亚属内的新组合。此外，我们建立被包菌科下的新属霍萨卡属（*Hosakaea*），以容纳近缘物种变紫奥氏块菌（*Octaviania violascens*）。最后，我们将德斯通茨亚属移至被包菌科，并修订该科的特征描述。本次在德斯通茨亚属与凯尔森属中提出的新组合，显著拓展了两个属的已知地理分布范围。粪便与土壤的元条形码分析数据还揭示了多个尚未被描述的物种，将两属的分布范围拓展至远超担子果采集记录所推测的范围。德斯通茨亚属在腐生营养型鬼笔目中的系统分类位置表明，该属并非外生菌根真菌，本文还讨论了此次系统学修订的生态学意义。

搜集汇总

背景与挑战

背景概述

该数据集提供了对稀有块菌形成真菌属Destuntzia和Kjeldsenia的系统修订研究，通过形态学和系统发育分析，重新评估了这些属的分类地位，并建立了新属Hosakaea。数据集包含多基因位点序列比对和系统发育树文件，支持了Destuntzia属于Claustulaceae科、与Kjeldsenia密切相关的结论，同时揭示了这些属的地理分布扩展和生态意义。