Micromphale sect. Perforantia (Agaricales, Basidiomycetes); expansion and phylogenetic placement

DNA sequences show that the traditional genus Micromphale appears to be polyphyletic. Nuclear ribosomal LSU and ITS DNA sequences place Micromphale sect. Perforantia Singer (typus sect. M. perforans) within Gymnopus, comprising a clade sister to a mixture of traditional Gymnopus taxa including G. fusipes (typus generis) plus traditional Marasmius sect. Androsacei. This study enlarges sect. Perforantia and shows that sect. Perforantia is a clade separate from those including Micromphale sect. Micromphale and sect. Rhizomorphigena. A new subsection Pinophili is proposed to include new species G. pinophilus and G. ponderosae. Eleven taxa are accepted at species rank, of which nine are proposed as new, mostly morpho-taxa.

DNA序列分析表明，传统界定的微囊伞属（Micromphale）为多系群。基于细胞核核糖体大亚基（LSU）与内转录间隔区（ITS）的DNA序列数据，将Singer发表的微囊伞属穿孔组（Micromphale sect. Perforantia，组模式种为穿孔微囊伞M. perforans）归入裸柄伞属（Gymnopus）；该类群构成一个姐妹支，其姊妹类群包含传统裸柄伞属类群（含属模式种柄裸柄伞G. fusipes）以及传统小皮伞属点地梅组（Marasmius sect. Androsacei）的混合类群。本研究扩充了穿孔组的分类范畴，并证实穿孔组是一个独立的演化支，与包含微囊伞属微囊组（Micromphale sect. Micromphale）和根状茎组（sect. Rhizomorphigena）的类群支系相互独立。本研究提议建立新的亚组松生亚组（Pinophili subsect.），以纳入新种松裸柄伞（G. pinophilus）与粗裸柄伞（G. ponderosae）。本研究共确认11个物种级分类单元，其中9个为新发表类群，且多数为形态分类单元。