Tuesday, November 8, 2022

[Botany • 2022] Hemipilia avisoides (Orchidaceae: Orchidoideae) • A New Species from Sichuan Province, China


 Hemipilia avisoides Y.Tang, X.M.Wang & H.Peng, 

in Wang, Tang, Peng & Peng, 2022.
雁字舌喙兰  ||  DOI: 10.3897/phytokeys.213.90377

Abstract
A new orchid species, Hemipilia avisoides, is described from Songpan County and Maoxian County, Sichuan Province, China. Morphologically, H. avisoides is most similar to H. hui, but can be distinguished by the combination of its involute middle lip lobe that is smaller than the lateral lobes, floral bracts that are 5 mm long and are always shorter than the ovary, a leaf that is appressed to the substrate and is adaxially green with white lines along 7–9 principal veins and the subterranean stem with a solitary sheath at its base. The floral morphology of H. avisoides is presented by utilising in vivo micro-CT scanning and 3D visualisation.

Keywords: Arid valley, Minjiang River Valley, Orchidinae, taxonomy


 Hemipilia avisoides Y.Tang, X.M.Wang & H.Peng, sp. nov.
   
Diagnosis: Similar to Hemipilia hui (Tang & F.T.Wang) Schuit., from which H. avisoides can be distinguished by a set of characteristics: mid-lobe involute, suboblong in apical view, 2.2 × 1.2 mm, trapeziform when flattened, smaller than lateral lobes; floral bracts 5 mm long, always shorter than ovary; leaf appressed to the substrate, adaxially green with white lines along 7–9 principal veins; stem subterranean, with one sheath at the base (Table 1).

Comparisons between living plants of  Hemipilia avisoides sp. nov. and H. hui in the wild
A–D habit, flowers, leaf and habitat of H. avisoides E–H habit, flowers, leaf and habitat of H. hui.
Photographs A–H by Y. Tang.

Leaves of  Hemipilia avisoides sp. nov. and some related species in H. sect. Hemipilia sensu Tang et al. (2015) 
 H. avisoides B H. thailandica C H. hemipilioides
D H. brevicalcarata E H. galeata F H. cordifolia.
Photographs A–F by Y. Tang.

Distribution and habitat: Hemipilia avisoides is currently known from two localities in Songpan County, which are ca 11.2 km apart along the Minjiang River Valley and one locality in Maoxian County according to the collection by S.-Y. Chen et al. in 1958. Individuals of the new taxon occur under arid-valley shrubs and on moss-covered rocks (see Discussion).

Etymology: Latin avis, bird, and suffix -oides, similar, alluding to appearance of flower arrangement simulating flying birds with flapped wings.

Chinese name: 雁字舌喙兰 (Chinese Pinyin: yànzì shéhuìlán).


Xue-Man Wang, Ying Tang, Pei-Hao Peng and Hua Peng. 2022. Hemipilia avisoides (Orchidaceae), A New Species from Sichuan Province, China. PhytoKeys. 213: 1-18.  DOI: 10.3897/phytokeys.213.90377