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| Gastrochilus heminii M.Liao, B.Xu & Yue H.Cheng, in Liao, Cheng, Zhang, Feng, Liu, ... et Xu, 2022. |
Abstract
Gastrochilus heminii (Orchidaceae), a new orchid species from Sichuan Province, Southwest China, is described and illustrated. It morphologically resembles G. affinis and G. yei, but differs markedly from the former in having a thinner and slightly rolled downwards reniform epichile and the central thickened purple-red mat with irregular folds (vs. subtriangular epichile curves upwards, with 2 thick, brown to purplish-brown median ridges from base to apex), and can be clearly distinguished from the latter by having reniform epichile with lobed apex and subconical hypochile with bilobed apex that splits into two conical protrusions (vs. semi-rounded epichile not lobed and subconical hypochile not bilobed). The results of molecular phylogenetic analysis based on nuclear ribosome internal transcribed spacer (nrITS) and four chloroplast DNA fragments (matK, psbA-trnH, psbM-trnD, and trnL-F) of 36 Gastrochilus species showed that G. heminii was closely related to G. affinis and G. distichus.
Keywords: Gastrochilus, morphological, Orchidaceae, phylogeny, taxonomy
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| Gastrochilus heminii M.Liao, B.Xu & Yue H.Cheng, A flowering plant B young leaves (B1: front view; B2: reverse view) C old leaves (C1: front view; C2: reverse view) D raceme and capsule (side view) E–I flowers (different views) J anatomy of flower (J1: dorsal sepals; J2 and J3: lateral sepals; J4 and J5: petals; J6: labellum) K hypochile (dorsal view) L stamens. |
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| Comparison of three taxa of Gastrochilus A, B Gastrochilus heminii C, D G. affinis E, F G. distichus G, H G. yei. [Images C, D cited from Jalal et al. 2020; image E reproduced from website (http://www.orchidspecies.com/gastdistichus.htm); image F cited from Kumar et al. 2014, which was photographed by Xiao-Hua Jin; images G and H cited from Li et al. 2021]. |
Gastrochilus heminii M.Liao, B.Xu & Yue H.Cheng, sp. nov.
Diagnosis: Gastrochilus heminii is morphologically related to G. affinis and G. yei based on vegetative and floral characteristics such as similar habit, distichous and alternate leaves, epichile surface smooth and glabrous, sepals and petals with purplish-red patches. However, it can be differentiated from G. affinis on the basis of flower numbers (1–2 in the former vs. 1–4 in the latter), peduncle length (0.4–0.7 cm in the former vs. 1.5–2.0 cm in the latter) and an additional morphological characteristic: young leaves are densely covered with purple-red spots and old leaves have hardly any purple-red spots in the former (both have purple-red spots in the latter); the reniform epichile is rolled downwards, smooth and glabrous above, and central thickened purple-red mat with irregular folds in the former (subtriangular epichile curves upwards, with 2 thick, brown to purplish-brown median ridges from base to apex in the latter). It differs from G. yei by having reniform and lobed epichile (not lobed in the latter), apex of hypochile bilobed and splits into two conical protrusions (not bilobed in the latter), apex of the leaf with 1–2 lobules, lobes setaceous (apex of leaf with a tine in the latter).
Etymology: Named in honor of Mr. He-Min Zhang, the advocate of the panda “Release to the Forest”, one of the pioneers of panda research in China, renowned as the “father” of pandas, in recognition of his contribution to the conservation of flora and fauna in the region which was one of the earliest reserves dedicated to preserving the habitat of wild pandas. A Chinese name, he min peng ju lan (和民盆距兰), is suggested here.
Min Liao, Yue-Hong Cheng, Jun-Yi Zhang, Yu Feng, Gui-Ying Liu, Ping Ye, Sen-Long Jin, Hong-Qiang Lin and Bo Xu. 2022. Gastrochilus heminii (Orchidaceae, Epidendroideae), A New Species from Sichuan, China, based on Molecular and Morphological Data. PhytoKeys. 215: 95-106. DOI: 10.3897/phytokeys.215.91061
