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. 2026 Oct 19;280:165–179. doi: 10.3897/phytokeys.280.206936

Gastrochilus immaculatus (Orchidaceae, Epidendroideae), a new epiphytic orchid from Chongqing, Southwest China

Jun-Yi Zhang 1,2,3, Min Liao 1, Pan-Yan Yang 4, Yue-Hong Cheng 4, Jin-Zhong Wu 5, Peng-Cheng Zhang 5, Ding-Xiang Yu 6,✉, Feng Chen 7,✉, Bo Xu 1,3,✉
PMCID: PMC13717513  PMID: 42959720

Abstract

Gastrochilus immaculatus (Orchidaceae) is described and illustrated as a new species from Chongqing, southwestern China, where it grows epiphytically on tree trunks or rock walls in evergreen broad-leaved forests. It differs from the morphologically similar G. fargesii by its shorter stems, broader falcate-oblong leaves, and, especially, its golden-yellow immaculate flowers with a rather acute apex of the hypochile. Phylogenetic analyses based on nuclear ITS and four chloroplast markers (matK, psbA–trnH, psbM–trnD, and trnL–F) strongly support it as a sister species of G. fargesii within G. sect. Acinacifolii. Only three small subpopulations were discovered within a scenic spot in a deep limestone valley in southern Chongqing, warranting a preliminary IUCN classification of Critically Endangered (CR). This discovery also highlights the overlooked epiphytic orchid diversity along the mountain ranges surrounding the Sichuan Basin.

Key words: Chongqing, Gastrochilus , new species, Orchidaceae , phylogeny

Introduction

The epiphytic orchid genus Gastrochilus D.Don (Don 1825) comprises approximately 89 species distributed from tropical to warm-temperate Asia (Tsi 1996, 1999; Liu et al. 2019; Govaerts et al. 2021; Zhou et al. 2021; Zhang et al. 2022; Ya et al. 2023; Zhang et al. 2024a, 2024b; Xiong et al. 2025; POWO 2026). Members of the genus are readily recognized by their saccate hypochile that forms a distinct spur, together with two sub-globose pollinia attached to a slender stipe (Pridgeon et al. 2014; Zhang et al. 2024a). Most species were discovered in the past 20 years, and more than 20 species were described in the most recent 5 years, particularly from the regions adjacent to the Sichuan Basin (Liu et al. 2019; Rao et al. 2019; Wu et al. 2019; Liao et al. 2022; Nguyen et al. 2022; Zhang et al. 2022; Lee et al. 2023; Liu et al. 2023; Ya et al. 2023; Zhang et al. 2024a; Zhang et al. 2024b; Zhou et al. 2024; Xiong et al. 2025; Zhu et al. 2025). With the accumulated molecular data and morphological evidence, this genus was subdivided into six sections (Zhang et al. 2024a).

In September 2025, during a survey in Qijiang District, Chongqing, Southwest China, an unusual flowering Gastrochilus species was encountered in an evergreen broad-leaved forest at elevations between 800 and 1,100 m. The locality is close to Jinfo Mountain in Nanchuan District, Chongqing (Fig. 1), where Yi et al. (2010) collected and described G. brevifimbriatus S.R. Yi (=G. fargesii (Kraenzl.) Schltr. according to Liu et al. 2023). This orchid also resembles G. fargesii, which is a member of G. sect. Acinacifolii Q. Liu & J.Y. Gao ex Jun Y. Zhang & H. He, characterized by falcate-oblong leaves and a subtriangular epichile with a central thickened cushion, an adaxially glabrous surface, and a lacerate or erose in margin (Zhang et al. 2024a). However, it showed a remarkable difference in flower color, being yellow without deeper spots. Based on previous studies (Liao et al. 2022; Zhang et al. 2022; Zhang et al. 2024a, 2024b; Zhu et al. 2025), this species is here named G. immaculatus, with the hypothesis that it is a new member of the same section as G. fargesii.

Figure 1.

Figure 1.

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Maximum likelihood phylogenetic tree of Gastrochilus, including 60 taxa, based on the combined nrITS and four plastid markers (matK, psbA–trnH, psbM–trnD, and trnL–F). Values before the slash indicate Bayesian posterior probabilities, and numbers after the slash indicate ML bootstrap support values for major lineages. An asterisk (*) indicates that a node is not supported in the analysis. The two accessions of the inferred new species are highlighted in red, and the colors of the terminal nodes correspond to the six sections of Gastrochilus defined in Zhang et al. (2024a).

Materials and methods

Morphological analyses

Field collections of herbarium specimens and silica-gel-dried leaves of Gastrochilus immaculatus were carried out in Heishan Valley, Qijiang District, Chongqing, Southwest China. Morphological observations and measurements were performed on both living plants and dried voucher specimens, which are deposited at CDBI (herbarium acronyms follow Thiers 2026). Descriptive terminology followed Beentje (2016), and the description order and arrangement referred to Chen et al. (2009).

DNA extraction, amplification, and sequencing

For Gastrochilus immaculatus, leaf samples from two individuals (collected from two different subpopulations) were used, and for G. fargesii, three accessions were included: S18942 (from Ya et al. 2023) and two additional samples (ZJY331 and ZJY335) added in this study. Total DNA was extracted exclusively from silica-gel-dried leaves using a Plant DNA Isolation Kit (Cat. No. DE-06111). Following the phylogenetic protocols for Gastrochilus established by Liu et al. (2019) and Zhang et al. (2024a), the same primer sets were employed to amplify the nuclear ribosomal internal transcribed spacer (nrITS) and four chloroplast markers (matK, psbA–trnH, psbM–trnD, and trnL–F) via polymerase chain reaction (PCR). All amplified products were sequenced by TSINGKE Biotech Co. Ltd. (Chengdu, China). The manually edited sequences were submitted to GenBank (Table A1).

Phylogenetic analyses

Sequence data for 60 species included in the phylogenetic analyses were retrieved from GenBank, originally published by Liu et al. (2019), Ya et al. (2023), Zhang et al. (2024a, 2024b), Xiong et al. (2025), and Zhu et al. (2025), or were newly generated in this study. Sequence editing was conducted using Sequencher v. 4.1.4 (Gene Codes, Ann Arbor, Michigan, USA), and alignment was performed with MAFFT v. 7.475 (Katoh and Standley 2013) under default parameters. Prior to combining the datasets, congruence between the nrITS and the four plastid markers was checked. The incongruence length difference (ILD) test was used to quantify the conflicts between nuclear DNA and plastid DNA data in PAUP v. 4.0a169 (Darlu and Lecointre 2002; Cummings 2004). Phylogenetic analyses were conducted on the combined matrix, with six species of Aeridinae (Luisia Gaudich., Saccolabium Blume, Holcoglossum Schltr., and Pomatocalpa Breda) designated as outgroups following Liu et al. (2019) and Zhang et al. (2024a). The best-fit nucleotide substitution model (GTR+I+G) was selected using jModelTest v. 2.1.6 (Posada 2008) based on the corrected Akaike Information Criterion (AICc). Maximum likelihood (ML) and Bayesian inference (BI) approaches were used for tree reconstruction. BI was run in MrBayes v. 3.2.7a (Ronquist and Huelsenbeck 2003) with two independent Markov chain Monte Carlo (MCMC) runs, each lasting 20 million generations and sampling every 1,000 generations. The first 25% of sampled trees were discarded as burn-in, and the remaining trees were used to build a majority-rule consensus tree. ML analysis was carried out with IQ-TREE v. 1.4.2 (Nguyen et al. 2014), and branch support was assessed using 2,000 bootstrap replicates. The resulting trees were visualized using Chiplot (Xie et al. 2023).

Results

The aligned nrITS dataset comprised 687 nucleotides, of which 201 were variable. The combined plastid dataset included four markers (matK: 809 bp; psbA–trnH: 680 bp; psbM–trnD: 957 bp; trnL–F: 1,010 bp), totaling 3,456 bp in length with 213 variable sites. The ILD test (P = 0.15) showed that the plastid DNA and nrITS were suitable for combined analysis. In agreement with earlier studies, Gastrochilus was recovered as a well-supported monophyletic group, with high posterior probabilities (PP) and bootstrap probabilities (BP). Likewise, the previously recognized subdivision within the genus was corroborated, as the clades corresponding to the six sections received strong support (Fig. 1). The two accessions (ZJY332 and ZJY333) of G. immaculatus, collected from two sites, formed a well-supported lineage (BI/ML = 1/100; Fig. 1). This lineage was sister to the clade comprising three accessions of G. fargesii (BI/ML = 1/95; Fig. 1). Among the latter, the accession S18942 from Ya et al. (2023) clustered with the two additional accessions newly obtained in this study, i.e., ZJY331 (from its type locality, Chengkou County, Chongqing) and ZJY335 (from Jinfo Mountain, Nanchuan, Chongqing). The subclade comprising G. immaculatus and G. fargesii was further nested with other species of G. sect. Acinacifolii (Fig. 1).

Morphologically, Gastrochilus immaculatus showed a floral size similar to that of G. fargesii and G. guangtungensis Z. H. Tsi. However, it was closer to G. fargesii than to G. guangtungensis in other floral and vegetative characters. Their morphological comparisons are summarized in Table 1.

Table 1.

Morphological comparisons of Gastrochilus immaculatus with two related species of G. sect. Acinacifolii.

Character G. immaculatus G. fargesii G. guangtungensis
Stem length 2.0–8.0 cm 3.0–13.0 cm 6.0–17.0 cm
Leaves Broad falcate-oblong, 2.5–7.4 × 0.8–1.5 cm Narrowly falcate-linear, 2.0–4.5 × 0.4–0.6 cm Falcate-oblong or oblong, 4.5–9.0 × 0.6–1.1 cm
Flowers ca. 1.2 × 1.4 cm, golden yellow without spots ca. 0.9 × 1.2 cm, yellowish-green with purplish-red spots ca. 1.0 × 1.2 cm, yellow with purplish-red spots
Dorsal sepal Elliptic, 4.6–6.8 × 3.6–4.5 mm, golden yellow without spots Oblong-elliptic, ca. 4.0 × 2.0 mm, yellowish green with purplish-red spots Obovate, 5.0–6.0 × 2.2–2.7 mm, yellow with purplish-red spots
Lateral sepals Obovate, 5.0–6.8 × 3.2–4.5 mm, golden yellow without spots Similar to dorsal sepal Similar to dorsal sepal
Petals Obovate, 4.8–6.5 × 3.2–4.2 mm, golden yellow without spots Narrowly oblong, ca. 3.0 × 1.5 mm, yellowish green with purplish-red spots Obovate, 4.5–5.8 × 2.0–2.5 mm, yellow with purplish-red spots
Epichile (lip lamina) Broadly triangular, 5.8–7.2 × 3.0–4.5 mm, the golden yellow cushion without spots Transversely oblong, broadly triangular, 2.0–3.0 × 4.0–4.5 mm, the yellowish-white cushion with purplish-red spot Subovate-triangular, ca. 2.5 × 3.0 mm, the yellow cushion with purplish-red spot
Hypochile Hypochile subconic, golden yellow, 4.8–6.5 mm tall, 4.2–5.0 × 3.0–3.6 mm in diam., apex acute Hypochile subconic, yellowish-white, ca. 2.2 mm tall, ca. 3.0 mm in diam., apex obtuse Hypochile subglobose, white, ca. 3.5 mm tall, ca. 4.5 mm in diam., apex obtuse
Flowering season September to October May to June October
Distribution Qijiang, Chongqing Chengkou, Nanchuan, Chongqing; Zunyi, Libo, Guizhou Wengyuan, Guangdong
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Discussion

The two newly generated accessions of Gastrochilus immaculatus were almost identical in the combined ITS and four plastid markers, although they were from different sites separated by cliffs in a deep limestone valley ca. 3.5 km long. This confirms that they both belong to the same species. As previously hypothesized, the general falcate-oblong leaves and nearly triangular and erose-margined epichile of G. immaculatus place it in G. sect. Acinacifolii (Zhang et al. 2024a). The results of phylogenetic analysis based on molecular data support the hypothesis that G. immaculatus is a member of this section and sister to G. fargesii, to which it is morphologically most similar. Its morphological differences (as shown in Table 1 and the following diagnosis) from G. fargesii are relatively stable in stem length, leaf width, and flower color. It is therefore concluded that G. immaculatus merits recognition as a new epiphytic orchid species.

With the discovery of Gastrochilus immaculatus, the number of species ascribed to G. sect. Acinacifolii amounts to 13 species (Zhang et al. 2024a). To date, nine of the known species in this section have been sampled for phylogenetic studies, and all were resolved in a strongly supported clade within the genus Gastrochilus (Liu et al. 2019; Zhang et al. 2024a, 2024b; Zhu et al. 2025). Increased samples by recent field investigations and comparative morphological studies (Liu et al. 2019; Zhang et al. 2024a) have both revealed the distributions of two species reaching southern China (G. acutifolius (Lindl.) Kuntze from eastern India to southwestern Yunnan and G. minutiflorus Aver. from Vietnam to southeast Yunnan) and reinstated the identity of G. somai (Hayata) Hayata as a separate species rather than a synonym of G. japonicus (Makino) Schltr. (Tsi 1999; Chen et al. 2009). G. fargesii is the only species in this section distributed in northeast Chongqing, Southwest China; its type materials were collected from the Daba Mountains in Chengkou County. It was formerly reported to have a distributional range extending either from the Daba Mountains to western Sichuan (Qionglai Mountains) (Tsi 1999) or as far as southeastern Yunnan (Chen et al. 2009). A review of those specimens identified as this species during previous studies (see Zhang et al. 2024a, 2024b; Zhu et al. 2025) led to the exclusion of its reported distributions in both Sichuan and Yunnan due to misidentifications, while confirming its presence in southern Chongqing (Nanchuan) and northern (Zunyi) and southeastern Guizhou (Libo) (Fig. 4). However, this still indicates that G. fargesii is isolated from other members of this section. The three sites of G. immaculatus are not far from a population of G. fargesii in Nanchuan (southern Chongqing) (Yi et al. 2010), and the two species show both morphological and phylogenetic affinities. This may suggest that members of the section continued to diversify as they expanded northwards along the mountain ranges bordering the Sichuan Basin, although most species in this section were found farther south (Tsi 1996, 1999; Chen et al. 2009; Liu et al. 2019; Zhang et al. 2024a). Further explorations in adjacent regions may identify additional species in this section or reveal overlooked species diversity among those tree-trunk epiphytic orchids.

Figure 4.

Figure 4.

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Distribution map of Gastrochilus immaculatus and its sister species, G. fargesii.

Taxonomic treatment

Gastrochilus immaculatus

Jun Y.Zhang & F.Chen sp. nov.

33502E14-D306-5CB0-BFC0-71CB8E119D65

urn:lsid:ipni.org:names:77413061-1

Figs 2A, 2B, 3

Figure 2.

Figure 2.

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Comparison of two sister species of Gastrochilus. A. Flowering plants of G. immaculatus growing on tree trunks from the Jiaozigou subpopulation. B. Flowering plants of G. immaculatus growing on rock walls from the Houwangdong subpopulation. C. Flowering plants of G. fargesii growing on tree trunks from Jinfo Mountain, Nanchuan (southern Chongqing). D. Flowering plants of G. fargesii growing on tree branches from Chengkou (northeastern Chongqing). E. Morphological details of G. fargesii from Jinfo Mountain, Nanchuan (southern Chongqing) [a. flowering plant; b. leaves (front view); c. leaves (abaxial view); d. inflorescences (front view); e. inflorescences (abaxial view); f. flowers (front view); g. flowers (side view); h. hypochile (side view); i. dissection of a flower (I1: dorsal sepal; I2–3: lateral sepals; I4–5: petals; I6: labellum); j. anther cap; k. pollinarium with pollinia]. F. Morphological details of G. fargesii from Chengkou (northeastern Chongqing) [a. flowering plant; b. leaf apex (front view); c. inflorescences; d. flowers (front view); e. dissection of a flower (E1: dorsal sepal; E2–3: lateral sepals; E4–5: petals; E6: labellum); f. hypochile (side view); g. hypochile (abaxial view); h. anther cap; i. pollinarium with pollinia]. Images A, B. Photographed by Feng Chen; C. photographed by Ce-Hong Li; D, F. photographed by Qiang Liu; E. photographed by Jun-Yi Zhang.

Figure 3.

Figure 3.

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Gastrochilus immaculatus. A. Flowering plant; B. leaves (front view); C. leaves (abaxial view); D. leaf apex (front view); E. inflorescences; F. flowers (front view); G. flowers (side view); H. flowers (abaxial view); I. dissection of a flower (I1: dorsal sepal; I2–3: lateral sepals; I4–5: petals; I6: labellum); J. pollinarium with pollinia; K. anther cap; L. stigma. Images A–L. Photographed by Feng Chen.

Type.

China • Chongqing: Heishan Valley, Qijiang, growing on tree trunks in evergreen broad-leaved forests; elev. ca. 870 m, 28°52'41"N, 107°01'39"E, in flower, 26 September 2025, Jun-Yi Zhang & Feng Chen ZJY211 (holotype CDBI!; isotype CQNM!)

Diagnosis.

It morphologically resembles G. fargesii but differs from the latter by its shorter stem (2.0–8.0 vs. 3.0–13.0 cm), broader falcate-oblong leaves (vs. narrowly falcate-linear), and almost pure golden-yellow flowers (vs. yellowish-green with purplish-red spots). Additionally, its hypochile has a rather acute apex (vs. obtuse apex).

Description.

Tree epiphytes, pendent, 4.2–12.5 cm long. Roots vermiform, 6.0–20.0 cm long, ca. 2.0 mm in diameter. Stem sometimes branched, 2.0–8.0 cm long, ca. 3.0 mm in diameter, with many leaves. Leaves distichous, blade thickly fleshy, falcate-oblong, 2.5–7.4 × 0.8–1.5 cm, apex acute and with two or three short awns. Inflorescences several, subumbellate, 2–5-flowered; peduncle curved upward and thickened, 3.0–8.0 mm long, proximally covered with one sheath; floral bracts ovate-lanceolate, 0.6–1.2 mm long, apex acute; pedicellate ovary, 0.5–0.9 cm long. Flowers spreading, ca. 1.2 × 1.4 cm, golden yellow without spots; sepals and petals golden yellow on both sides; dorsal sepals elliptic, 4.6–6.8 × 3.6–4.5 mm, apex obtuse; lateral sepals obovate, 5.0–6.8 × 3.2–4.5 mm, apex obtuse; petals obovate, 4.8–6.5 × 3.2–4.2 mm, apex obtuse, base narrowed; lip with an epichile and a saccate hypochile; epichile broadly triangular, 5.8–7.2 × 3.0–4.5 mm, adaxially glabrous, with a golden-yellow cushion extending to front wall of hypochile, margin ± erose, apex obtuse; hypochile subconic, golden yellow, 4.8–6.5 mm tall, 4.2–5.0 × 3.0–3.6 mm in diam., acute at the apex; column cylindrical, ca. 0.8 mm; anther cap galeate with two chambers, ca. 0.9 × 0.6 mm; rostellum bilobed; pollinarium ca. 0.7 mm long; pollinia 2, ca. 0.3 × 0.2 mm, yellow, subglobular, porate; stigma deeply sunken, inverted V-shaped, ca. 0.3 mm long, pink. Fruits not seen.

Habitat and distribution.

Gastrochilus immaculatus is currently known only from Heishan Valley, Qijiang District, Chongqing, southwestern China (Fig. 4). Three subpopulations are currently known, located at Jiaozigou, Heishangu, and Houwangdong in Heishan Town, respectively. It is epiphytic on tree trunks or rock walls in evergreen broad-leaved forests at elevations between 850 and 1,030 m.

Conservation status.

The three known subpopulations comprise a total of over 50 mature individuals. Based on the IUCN Red List Categories and Criteria (IUCN 2012), its area of occupancy (AOO) is estimated to be 8 km2 (calculated using the standard 2 × 2 km grid cell method), and its extent of occurrence (EOO) is ca. 1.3 km2 (reported as 8 km2 following IUCN guidelines where EOO<AOO). Because all three subpopulations are restricted to a single valley subject to continuous anthropogenic disturbance and habitat degradation associated with tourism, they represent a single location. Furthermore, a continuous decline in the quality and extent of its habitat has been observed. Although the total number of mature individuals exceeds 50 (which precludes evaluation under Criterion D for CR), the geographical range parameters strictly meet the thresholds for Critically Endangered under Criterion B. Therefore, Gastrochilus immaculatus is formally assessed as Critically Endangered (CR): CR B1ab(iii)+2ab(iii). Although further systematic field investigations in adjacent potential habitats in Guizhou Province are recommended, the present assessment strictly reflects its conservation status based on all currently available field data.

Phenology.

Flowering from September to October.

Etymology.

The specific epithet ‘immaculatus’ refers to the spotless sepals, petals, and lip in the flower of this new orchid. Its Chinese name is proposed as su xin peng ju lan (素心盆距兰).

Other specimens examined.

Gastrochilus fargesii. China • Chongqing [previous including in Sichuan]: Chengkou Xian [Tschen Keou], Mingzhong [Moung Moung Ky (蒙蒙溪)], 1600 m, 27 August 1893, P. G. Farges 1236 (Isotype: IBSC!); Nanchuan County, Houhe, Jinfo Mountain, epiphytic on trunk, 680 m, 29 August 2007, Yi Si Rong 075631 (IMC!), ibid., 720 m, 03 July 2017, Qiang Liu 457 (HITBC!).

Supplementary Material

XML Treatment for Gastrochilus immaculatus

Acknowledgments

The authors thank the staff of CDBI, IBSC, PE, HITBC, and IMC for their kind assistance in facilitating access to herbarium specimens. The authors also thank Dr. Qiang Liu, Ms. Lu Zhu, and Mr. Ce-Hong Li for their assistance with species identification and imagery. This research was supported by the Biological Resources Programme, Chinese Academy of Sciences (CAS-TAX-24-053); the National Natural Science Foundation of China (32500332); the Wild Plants Sharing and Service Platform of Sichuan Province; and the 2025 subsidy funds for Forestry and Grassland Ecological Conservation and Restoration (National Parks).

Appendix 1

Table A1.

Voucher information and GenBank accession numbers of DNA sequences of Gastrochilus used in phylogenetic inference.

Taxa Voucher Location nrITS matK psbA–trnH trnL–F psbM–trnD
G. acaulis (Lindl.) Kuntze — — KM583455 KM583465 — — —
G. acinacifolius Z.H.Tsi Z. J. Liu 3316 CHINA KJ733412 KJ733569 KJ733492 KJ733649 —
G. acinacifolius Z.H.Tsi Q. Liu 62 CHINA: Hainan (Baomeiling) MK357118 MK357138 MK357160 MK357208 MK357216
G. acinacifolius Z.H.Tsi ZJY289 CHINA: Yunnan (Malipo) OQ566796 OQ575562 OQ575590 OQ575530 OQ575619
G. acutifolius (Lindl.) Kuntze Q. Liu 05 CHINA: Yunnan (Jingmai) — MK357140 MK357162 — MK357230
G. acutifolius (Lindl.) Kuntze JK-DEBCR-mat-31(JK) — MW475270 MW433889 — — —
G. affinis (King & Pantl.) Schltr. Q. Liu 97 CHINA: Yunnan (Fugong) — MK357141 MK357163 — MK357141
G. alatus X.H.Jin & S.C.Chen Q. Liu 98 CHINA: Yunnan (Bingzhongluo) — — — — MK357228
G. alatus X.H.Jin & S.C.Chen ZJY297 CHINA: Yunnan — OQ575563 OQ575591 OQ575531 OQ575620
G. armeniacus Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY244 CHINA: Sichuan (Wenchuan) OP348889 OP373113 OP373119 OP373128 OP373123
G. armeniacus Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY285 CHINA: Sichuan (Wenchuan) OP348888 OP373114 OP373118 OP373127 OP373124
G. balangshanensis Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY317 CHINA: Sichuan (Wenchuan) PP960151 PP944493 PP944495 PP944499 PP944497
G. balangshanensis Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY318 CHINA: Sichuan (Wenchuan) PP960152 PP944494 PP944496 PP944500 PP944498
G. bellinus (Rchb.f.) Kuntze Q. Liu 52 CHINA: Yunnan (Lancang) KY966597 KY966884 — — —
G. bellinus (Rchb.f.) Kuntze Q. Liu 53 CHINA: Yunnan (Mengsong) MK357123 MK357142 MK357164 MK357202 MK357241
G. bellinus (Rchb.f.) Kuntze ZJY279 CHINA: Yunnan (Mengla) OQ566799 OQ575564 OQ575592 OQ575534 OQ575621
G. bernhardtianus J.D.Ya & D.Z.Li 20CS19022 CHINA: Yunnan (Lijiang) OR073404 OR772951 OR772951 OR772951 OR772951
G. bernhardtianus J.D.Ya & D.Z.Li 20CS19023 CHINA: Yunnan (Lijiang) OR073405 OR002167 OR002167 OR002167 OR002167
G. bigibbus (Rchb.f. ex Hook.f.) Kuntze Li 009 — — MN124439 MN124439 MN124439 MN124439
G. calceolaris D.Don Z. J. Liu 3769 CHINA KF545874 KF545885 KF545865 — KF545896
G. calceolaris D.Don Q. Liu 94 CHINA: Yunnan (Jingdong) MK357126 MK357144 MK357169 MK357205 MK357233
G. calceolaris D.Don ZJY281 CHINA: Yunnan (Malipo) — OQ575565 OQ575593 OQ575535 OQ575622
G. changjiangensis Q.Liu & M.Z.Huang Q. Liu 45 CHINA: Hainan (Changjiang) MK357124 — MK357166 — MK357236
G. ciliaris F.Maekawa Q. Liu 88 CHINA: Fuzhou — MK357148 MK357173 — MK357225
G. ciliaris F.Maekawa ZJY299 CHINA: Taiwan — OQ575566 OQ575594 — OQ575623
G. dasypogon (Lindl.) Kuntze Q. Liu 30 CHINA: Hainan (Baomeiling) MK357129 MK357149 MK357181 MK357197 MK357219
G. deminutus J.M.H.Shaw — — KY966600 KY966887 — — —
G. distichus (Lindl.) Kuntze Z. J. Liu 4755 CHINA KJ733414 KJ733571 KJ733494 KJ733651 —
G. distichus (Lindl.) Kuntze ZJY309 CHINA: Yunnan (Malipo) OQ566800 OQ575567 OQ575595 OQ575536 —
G. fargesii (Kraenzl.) Schltr. S18942 CHINA: Chongqing — OR002175 OR002175 OR002175 OR002175
G. fargesii (Kraenzl.) Schltr. ZJY331 CHINA: Chongqing (Chengkou) PZ281538 PZ282778 PZ282782 PZ282786 PZ282790
G. fargesii (Kraenzl.) Schltr. ZJY335 CHINA: Chongqing (Nanchuan) PZ281539 PZ282779 PZ282783 PZ282787 PZ282791
G. formosanus (Hayata) Hayata Z. J. Liu 4256 CHINA KJ733416 KJ733573 KJ733495 KJ733653 —
G. formosanus (Hayata) Hayata Q. Liu 91 CHINA: Yunnan (Gongshan) — — MK357174 — MK357226
G. formosanus (Hayata) Hayata ZJY276 CHINA: Hubei (Enshi) OQ566801 OQ575568 OQ575596 OQ575537 OQ575624
G. fuscopunctatus (Hayata) Hayata Q. Liu 86 CHINA: Taiwan (Hualian) — MK357150 MK357171 MK357192 MK357231
G. fuscopunctatus (Hayata) Hayata* — — — KX871233 KX871233 KX871233 KX871233
G. gongshanensis Z.H.Tsi ZJY295 CHINA: Yunnan (Malipo) — OQ575569 OQ575597 OQ575538 OQ575625
G. guangtungensis Z.H.Tsi Z. J. Liu 4127 CHINA KJ733417 KJ733574 KJ733496 KJ733654 —
G. guangtungensis Z.H.Tsi ZJY293 CHINA: Yunnan OQ566802 OQ575570 OQ575598 OQ575539 OQ575626
G. heminii M.Liao, B.Xu & Yue.H.Cheng ZJY241 CHINA: Sichuan (Wenchuan) ON286752 ON331126 ON331128 ON331130 ON331132
G. heminii M.Liao, B.Xu & Yue.H.Cheng ZJY283 CHINA: Sichuan (Wenchuan) ON286753 ON331127 ON331129 ON331131 ON331133
G. immaculatus Jun Y.Zhang & F.Chen ZJY332 CHINA: Chongqing (Qijiang) PZ281540 PZ282780 PZ282784 PZ282788 PZ282792
G. immaculatus Jun Y.Zhang & F.Chen ZJY333 CHINA: Chongqing (Qijiang) PZ281541 PZ282781 PZ282785 PZ282789 PZ282793
G. intermedius (Griff. ex Lindl.) Kuntze Q. Liu 38 CHINA: Yunnan (Yinchang) MK357121 MK357151 MK357172 MK357190 MK357213
G. japonicus (Makino) Schltr. Q. Liu 87 CHINA: Taiwan (Pingdong) KF545875 KF545886 KF545866 KF545897 —
G. japonicus (Makino) Schltr. — — — KX871236 KX871236 KX871236 KX871236
G. jiuzhaigouensis Jun Y.Zhang, D.L.Zhu & Y.Zhang ZJY329 CHINA: Sichuan (Jiuzhaigou) PV643100 PV645752 PV645754 PV645758 PV645756
G. jiuzhaigouensis Jun Y.Zhang, D.L.Zhu & Y.Zhang ZJY330 CHINA: Sichuan (Jiuzhaigou) PV643101 PV645753 PV645755 PV645759 PV645757
G. kadooriei Kumar et al. ZJY268 CHINA: Yunnan (Malipo) OQ566803 OQ575571 OQ575599 OQ575540 OQ575627
G. lihengiae J.D.Ya, H.Jiang & D.Z.Li 22CS21828 CHINA: Yunnan (Gongshan) OR073408 OR002168 OR002168 OR002168 OR002168
G. lihengiae J.D.Ya, H.Jiang & D.Z.Li 23CS24145 CHINA: Yunnan (Gongshan) OR073408 OR002169 OR002169 OR002169 OR002169
G. linearifolius Z.H.Tsi & Garay Q. Liu 711 MYANMA: Hkakaborazi MK357133 MK357136 MK357187 MK357194 MK357229
G. linii Ormerod Q. Liu 92 CHINA: Fuzhou — MK357152 MK357176 MK357198 MK357224
G. malipoensis X.H.Jin & S.C.Chen Q. Liu 71 CHINA: Yunnan (Nanwenghe) — MK357147 MK357177 MK357200 MK357235
G. malipoensis X.H.Jin & S.C.Chen ZJY288 CHINA: Yunnan (Malipo) OQ566804 OQ575572 OQ575600 OQ575541 OQ575628
G. matsuran (Makino) Schltr. — — KT338700 — — — —
G. minjiangensis Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY243 CHINA: Sichuan (Wenchuan) OP348887 OP373112 OP373117 OP373126 OP373122
G. minjiangensis Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY284 CHINA: Sichuan (Wenchuan) OQ566806 — — OQ575542 —
G. minutiflorus Aver. Q. Liu 37 CHINA: Yunnan (Malipo) — MK357153 MK357179 — MK357215
G. minutiflorus Aver. ZJY287 CHINA: Yunnan (Malipo) OQ566807 OQ575573 OQ575601 OQ575544 OQ575629
G. nanchuanensis Z.H.Tsi ZJY296 CHINA: Chongqing (Nanchuan) OQ566808 OQ575574 OQ575602 OQ575545 OQ575630
G. obliquus var. obliquus (Lindl.) Kuntze Q. Liu 708 MYANMA: Hponkanrazi Wildlife Sanctuary MK357131 MK357137 KJ733498 KJ733656 MK357211
G. obliquus var. obliquus (Lindl.) Kuntze Q. Liu 44 CHINA: Yunnan (Yinchang) MK357130 MK357154 MK357182 MK357195 MK357218
G. obovatifolius C.Xiong, X.Y.Fu & S.R.Yi XC24008 CHINA: Chongqing (Chengkou) PP949380 PP942372 PP942372 PP942372 PP942372
G. suavis Seidenf. ZJY277 CHINA: Yunnan OQ566809 OQ575575 OQ575603 OQ575546 OQ575631
G. suavis Seidenf. ZJY282 CHINA: Yunnan (Maguan) OQ566810 OQ575576 OQ575604 OQ575547 OQ575632
G. platycalcaratus (Rolfe) Schltr. Q. Liu 19 CHINA: Yunnan (Yinchang) MK357122 — MK357175 — MK357222
G. platycalcaratus (Rolfe) Schltr. ZJY300 CHINA: Yunnan (Mengla) OQ566811 — OQ575605 OQ575548 OQ575633
G. prionophyllus H.Jiang, D.P.Ye & Q.Liu ZJY291 CHINA: Yunnan OQ566812 OQ575577 OQ575606 OQ575549 OQ575634
G. pseudodistichus (King & Pantl.) Schltr. ZJY308 CHINA: Yunnan (Malipo) OQ566813 OQ575578 OQ575607 OQ575550 OQ575635
G. pseudodistichus (King & Pantl.) Schltr. ZJY290 CHINA: Yunnan (Maguan) OQ566814 OQ575579 OQ575608 OQ575551 OQ575636
G. rantabunensis S.Chow ex T.P.Lin Q. Liu 89 CHINA: Taiwan (Taipei) — MK357155 MK357184 MK357193 MK357223
G. rantabunensis S.Chow ex T.P.Lin ZJY303 CHINA: Taiwan OQ566815 OQ575580 OQ575609 OQ575552 OQ575637
G. raraensis Fukuy. Z. J. Liu 4798 CHINA KJ733420 KJ733577 KJ733499 KJ733657 —
G. setosus Aver. & Vuong ZJY304 Vietnam OQ566816 OQ575581 OQ575610 OQ575553 —
G. sinensis Z.H.Tsi ZJY228 CHINA: Zhejiang (Hangzhou) OM985813 OK042953 OK172399 OK172401 OQ575646
G. sinensis Z.H.Tsi S1109 CHINA: Sichuan (Wenchuan) OP348890 OP373115 OP373120 OP373129 OP373125
G. somai (Hayata) Hayata Q. Liu 36 CHINA: Fujian (Pingnan) MK357128 — MK357180 — MK357220
G. somai (Hayata) Hayata Li 073 — — MN124436 MN124436 MN124436 MN124436
G. sororius Schltr. — — ERR7622420 ERR7622420 ERR7622420 ERR7622420
G. wenshanensis Q.Liu, D.P.Ye & X.H.Jin ZJY292 CHINA: Yunnan (Maguan) OQ566820 OQ575586 OQ575615 OQ575558 OQ575642
G. sumartranus J.J.Sm. ZJY280 Vietnam OQ566818 OQ575583 OQ575612 OQ575555 OQ575639
G. sumartranus J.J.Sm. ZJY294 Vietnam OQ566819 OQ575584 OQ575613 OQ575556 OQ575640
G. tianbaoensis Q.Liu & Y.H.Tan ZJY275 CHINA: Yunnan (Malipo) — OQ575585 OQ575614 OQ575557 OQ575641
G. tianbaoensis Q.Liu & Y.H.Tan Q. Liu 63 CHINA: Yunnan (Malipo) MK357120 MK357157 MK357186 MK357207 MK357214
G. wolongensis Jun Y.Zhang, B.Xu & Yue H.Cheng ZJY240 CHINA: Sichuan (Wenchuan) OM985810 OK172400 OK172402 OK172404 OK172403
G. wolongensis Jun Y.Zhang, B.Xu & Yue H.Cheng S1108 CHINA: Sichuan (Wenchuan) OM985811 OM974209 OM974211 OM974210 OQ575647
G. xuanenensis Z.H.Tsi ZJY298 CHINA: Guizhou — OQ575587 OQ575616 OQ575559 OQ575643
G. yunlongensis W.H.Rao, L.J.Chen & Z.J.Liu ZJY301 CHINA: Yunnan — OQ575588 OQ575617 OQ575560 OQ575644
G. yunnanensis Schltr. Q. Liu 60 CHINA: Yunnan (Mengsong) MK165469 MK357158 MK357185 — MK357212
G. yunnanensis Schltr. ZJY278 CHINA: Yunnan (Xinping) OQ566821 OQ575589 OQ575618 OQ575561 OQ575645
G. zhenyuanensis Q.Liu & D.P.Ye Q. Liu 61 CHINA: Yunnan (Zhenyuan) MK357127 MK357146 MK357168 MK357199 MK357237
Holcoglossum amesianum (Rchb.f.) Christenson X.H. Jin 004/006 CHINA HQ404389 JF763779 HQ404439 — —
H. kimballianum (Rchb.f.) Garay X.H. Jin 017 CHINA HQ452901 JF763787 HQ404452 — —
Luisia magniflora Z.H.Tsi & S.C.Chen Z. J. Liu 3444 CHINA KJ733426 KJ733583 KJ733505 — —
Pomatocalpa diffusum Breda TBG145837 INDONESIA AB217576 AB217752 — EF670432 —
P. spicatum Breda Z. J. Liu 4589 CHINA KJ733438 KJ733595 KJ733518 KJ733675 —
Saccolabium pusillum Blume TBG144220 INDIA AB217580 AB217756 — — —
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Funding Statement

This research was supported by the Biological Resources Programme, Chinese Academy of Sciences (CAS-TAX-24-053); the National Natural Science Foundation of China (32500332); the Wild Plants Sharing and Service Platform of Sichuan Province and the 2025 subsidy funds for Forestry and Grassland Ecological Conservation and Restoration (National Parks).

Contributor Information

Ding-Xiang Yu, Email: yutengshu@163.com.

Feng Chen, Email: fengchen408@163.com.

Bo Xu, Email: xubo@cib.ac.cn.

Additional information

Conflict of interest

The authors have declared that no competing interests exist.

Ethical statement

No ethical statement was reported.

Artificial Intelligence (AI) use

The authors accept full responsibility for the content of the manuscript, including the disclosure of any use of AI.

No AI tools were used in the preparation of this manuscript.

Funding

This research was supported by the Biological Resources Programme, Chinese Academy of Sciences (CAS-TAX-24-053); the National Natural Science Foundation of China (32500332); the Wild Plants Sharing and Service Platform of Sichuan Province and the 2025 subsidy funds for Forestry and Grassland Ecological Conservation and Restoration (National Parks).

Author contributions

JYZ, ML, PYY, YHC, JZW, PCZ, DXY, BX, and FC discovered and identified the species. PYY, YHC, JZW, PCZ, DXY, and FC assisted in extensive field investigations and sample collection. JYZ and ML performed the experiments and analyzed the data. JYZ wrote the manuscript. DXY, BX, and FC revised the manuscript. All authors read and approved the final manuscript.

Author ORCIDs

J.-Y. Zhang https://orcid.org/0000-0001-8325-5954

M. Liao https://orcid.org/0000-0001-6777-8579

P.-Y. Yang https://orcid.org/0000-0003-0346-0443

Y.-H. Cheng https://orcid.org/0000-0001-6263-0989

D.-X. Yu https://orcid.org/0000-0002-7467-1769

F. Chen https://orcid.org/0000-0003-3398-8900

B. Xu https://orcid.org/0000-0003-3507-9321

Data availability

All of the data that support the findings of this study are available in the main text.

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Associated Data

This section collects any data citations, data availability statements, or supplementary materials included in this article.

Supplementary Materials

XML Treatment for Gastrochilus immaculatus
phytokeys.280.206936-treatment1.xml (16.8KB, xml)

Data Availability Statement

All of the data that support the findings of this study are available in the main text.

Articles from PhytoKeys are provided here courtesy of Pensoft Publishers

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