[Botany • 2025] Gastrochilus obovatifolius (Orchidaceae: Epidendroideae: Aeridinae) • A New Species from the Daba Mountains of Chongqing, China

 

Gastrochilus obovatifolius C.Xiong, X.Y.Fu & S.R.Yi, 

in Xiong, Fu, Tan, Huang, Zhang, Wang, Yang et Yi, 2025. 

倒卵叶盆距兰  ||  DOI: doi.org/10.3897/phytokeys.252.133501

Abstract

Gastrochilus obovatifolius, a new species discovered in the Dabashan of northeast Chongqing (China), is described and illustrated. The novelty morphologically resembles G. affinis, G. balangshanensis and G. heminii in having a glabrous and smooth epichile. but can be distinguished by the unique obovate shape of the leaves, smaller epichile, and flower color. 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 55 Gastrochilus species, support the inclusion of G. obovatifolius in G. sect. Microphylli, being most closely related to G. balangshanensis from Sichuan. The new species is a trunk epiphyte in evergreen broad-leaved forest.

Key words: Epidendroideae, Flora of Chongqing, G. sect. Microphylli, phylogeny, Qinling-Daba Mountains, taxonomy

Gastrochilus obovatifolius C.Xiong, X.Y.Fu & S.R.Yi, sp. nov., in vivo.
A flowering plant B inflorescence C leaves (C1–C3: front view, C4: back view, C5: close-up of leaf apex) D flower (front view) E flower (back view) F dissected flower (F1: dorsal sepal; F2: lateral sepals; F3: petals; F4: labellum) G flower (side view) H flower (top view) I pollinarium.

Gastrochilus obovatifolius C.Xiong, X.Y.Fu & S.R.Yi, sp. nov., an overview
A habit B stem apex C leaves (C1: front view, C2: back view, C3: side view) D flower (side view) E flower (front view) F flower (back view) G dissected flower (G1: dorsal sepal; G2: lateral sepals; G3: petals; G4: labellum) H pollinarium and anther cap.

 Gastrochilus obovatifolius C.Xiong, X.Y.Fu & S.R.Yi, sp.nov.

  

Diagnosis: Gastrochilus obovatifolius is most similar to G. balangshanensis., but differs by the longer stem (3–5 vs. 1.5–3.5 cm), obovate leaves (vs. nearly elliptic), and smaller sepals (ca. 5.0 × 3.0–4.0 vs. 5.6–6.4 × 4.8–5.2 mm) and hypochile (4.0–4.5 × 4.0–4.2 vs. 6.0–8.0 × 5.8–7.5 mm).

Etymology: The specific epithet ‘obovatifolius’ refers to the highly distinctive obovate leaves. The suggested Chinese common name is “dào luǎn yè pén jù lán (倒卵叶盆距兰)”.

 Chi Xiong, Xiao-Ying Fu, Ke Tan, Ya Huang, Hong-Jing Zhang, Yi-Chen Wang, Yu-Bing Yang and Si-Rong Yi. 2025. Gastrochilus obovatifolius (Orchidaceae, Aeridinae), A New Species from the Daba Mountains of Chongqing, China. PhytoKeys. 252: 25-40. DOI: doi.org/10.3897/phytokeys.252.133501