Spiranthes stylites is another long overlooked Asian Spiranthes with an unusual Sylvian habitat

We reexamine the taxon Spiranthes stylites, currently synonymized under S. australis, finding multiple lines of evidence from molecular phylogenetics, phenology, morphology, and habitat differences to support its distinction from other members of the Spiranthes sinensis species complex. Compared to its closest relative S. australis, S. stylites blooms earlier (June-early July vs. mid July-September), has consistently white tubular flowers (vs. commonly pink and pseudocampanulate), a distinctly long-clawed labellum (vs. shortly clawed), slender labellum nectar callosities (vs. globose), a proportionally larger column foot (ca. 50% of the length of the entire column vs. ca. 25%), and occurs in closed canopy woodlands (vs. open graminoid habitats). Spiranthes stylites is the only Spiranthes in the Eastern Hemisphere to have a woodland habitat. The recognition of S. stylites helps support white colored flowers as the plesiomorphic and most common floral condition in the complex, and indicat...

我们重新检视了当前被归为南方绶草（Spiranthes australis）异名的柱唇绶草（Spiranthes stylites），通过分子系统发育学、物候学、形态学及生境差异等多方面证据，证实其与绶草（Spiranthes sinensis）物种复合体内的其他类群存在显著区分。相较于其近缘类群南方绶草，柱唇绶草的花期更早（6月至7月初，而非7月中旬至9月）；其花始终为纯白色管状，而南方绶草的花通常呈粉色且为假钟形；唇瓣具明显长爪，南方绶草的唇瓣爪则较短；唇瓣蜜腺胼胝体纤细，南方绶草的该结构为球状；蕊柱足比例显著更大，约占整个蕊柱长度的50%（而南方绶草仅约25%）；且其生境为郁闭林冠的林地，而南方绶草多生于开阔禾草类生境。柱唇绶草是东半球唯一一种以林地为生境的绶草属植物。将柱唇绶草独立为有效类群，支持了白色花为该物种复合体的祖征及最常见花部性状的观点，同时表明……