A taxonomic revision of Herminium L.(Orchidoideae, Orchidaceae)

Herminium (Orchidaceae, Orchidoideae) is a medium-sized genus widespread in the northern hemisphere, with a clear centre of diversity in the Himalayas.

        Herminium L. is a widely distributed genus, ranging from Europe through most of continental Asia to Japan, the Malay Archipelago and New Guinea. However,most species are restricted to continental Asia, in particular to the Pan-Himalayan region, with only one, non-endemic species each in Europe (H. monorchis) and tropical Southeast Asia, including New Guinea (H. lanceum).

        In most of the earlier, floristic literature,Herminium was accepted in a broad sense. More recent authors,took a more narrow view to the genus and recognized a number of small satellite genera, including Androcorys Schltr., Bhutanthera J. Renz, Frigidorchis Z.J. Liu & S.C. Chen, and Porolabium T. Tang & F.T. Wang. Raskoti et al. (2016) found that these satellite genera as well as certain misplaced members of Peristylus Blume and Platanthera Rich. were nested within Herminium s.l. This led these authors to propose a broader delimitation of the genus, which we also adopt in this revision.

        As redefined, Herminium is a genus of 49 species of predominantly terrestrial orchids in the subtribe Orchidinae, characterized by having a (sub)globose tuber, a lip with a concave or spurred base, and pollinia with reduced caudicles.  Most species have quite small, greenish, whitish or yellowish flowers arranged in racemes. We present a comprehensive taxonomic revision of Herminium based on field observations and morphological studies, for which we examined about 2500 specimens. We recognize 49 species grouped into six formal sections, including one new species, Herminium tibeticum, from Tibet. We provide an identification key to the species, descriptions of the species, notes on ecology and distribution, and complete nomenclature for each species, including typifications. We here designate lectotypes for five species and reduce four taxa to synonymy.

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Habitat of Herminium. A H. chloranthum (Terrestrial) B H. quinquelobum (Epiphytic on tree trunk)

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Flowers of representive species of Herminium. A H. monorchis B H. latilabre C H. forceps D H. fallax E H. lanceum F H. edgeworthii G H. monophyllum H H. quinquelobum I H. pugioniforme

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New species Herminium tibeticum