Two new species of Cylindrolobus (Orchidaceae) from the eastern Himalayas

Abstract

Two new species, Cylindrolobus motuoensis and C. glabriflorus (Orchidaceae), from Southwestern China and north of Myanmar are described and illustrated with detailed photos. Cylindrolobus motuoensis is morphologically similar to C. gloensis and C. foetidus , but can be distinguished from them by having amplexicaul sterile bracts, dark red floral bracts, white flowers, falcate-lanceolate lateral sepals and central keel of lip running from base to the tip of mid-lobe. Cylindrolobus glabriflorus is similar to C. hegdei and C. tenuicaulis but differs from them by having longer and wider leaves, obovate bracts, and the reddish brown central papillate keel of lip.

Full text

Two new species of Cylindrolobus (Orchidaceae) from the eastern Himalayas 107
Two new species of Cylindrolobus (Orchidaceae)
from the eastern Himalayas
Ji-Dong Ya1, Xiao-Hua Jin2, Cheng Liu1
1 Germplasm Bank of Wild Species, Kunming Institute of Botany, Chinese Academy of Sciences, Lanhei Road
132, Heilongtan, Kunming, Yunnan, 650201, China 2 State Key Laboratory of Systematic and Evolutionary
Botany and Herbarium, Institute of Botany, Chinese Academy of Sciences, Nanxincun20, Xiangshan, Beijing,
100093, China
Corresponding author: Xiao-Hua Jin (xiaohuajin@ibcas.ac.cn)
Academic editor: Cai Jie|  Received 27 February 2019 |Accepted 18 May 2019 |  Published 29 August2019
Citation: Ya J-D, Jin X-H, Liu C (2019) Two new species of Cylindrolobus (Orchidaceae) from the eastern Himalayas. In:
Cai J, Yu W-B, Zhang T, Li D-Z (Eds) Revealing of the plant diversity in China’s biodiversity hotspots. PhytoKeys 130:
107–113. https://doi.org/10.3897/phytokeys.130.33989
Abstract
Two new species, Cylindrolobus motuoensis and C. glabriorus (Orchidaceae), from Southwestern China and
north of Myanmar are described and illustrated with detailed photos. Cylindrolobus motuoensis is morphologi-
cally similar to C. gloensis and C. foetidus, but can be distinguished from them by having amplexicaul sterile
bracts, dark red oral bracts, white owers, falcate-lanceolate lateral sepals and central keel of lip running from
base to the tip of mid-lobe. Cylindrolobus glabriorus is similar to C. hegdei and C. tenuicaulis but diers from
them by having longer and wider leaves, obovate bracts, and the reddish brown central papillate keel of lip.
Keywords
Taxonomy, Orchidaceae, Cylindrolobus, new species, China
Introduction
e genus Cylindrolobus Blume consists of 60‒70 species, distributed in the tropical
region from East Himalaya, China, Southeast Asia to New Guinea (Chen et al. 2009,
Ormerod 2014, Ng et al. 2018). Cylindrolobus was originally proposed as a section of
Eria Lindl., Pridgeon et al. (2005) suggested that Cylindrolobus should be subsumed
into Callostylis Blume. Recent molecular and morphological studies suggest that Cylin-
drolobus is a distinct genus, characterized by a multi-noded stem with leaves at apex,
short inorescences with one to several owers and conspicuous and colorful bracts
(Chen et al. 2009, Ng et al. 2018).
PhytoKeys 130: 107–113 (2019)
doi: 10.3897/phytokeys.130.33989
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Ji-Dong Ya et al. / PhytoKeys 130: 107–113 (2019)
108
Materials and methods
Living plants were collected from Xizang (Tibet) Autonomous Region of China and
north of Myanmar during the botanical expeditions in 2016 and in 2018. e shapes,
colors of owers and other details of the plants observed, measured and photographed,
as well as specimens collected, were based on living materials from 2017 to 2019. Mor-
phological photographs of the lip, column and pollinia were taken using an Olympus
SZX16. All voucher specimens were deposited in KUN (Herbarium of Kunming In-
stitute of Botany, Chinese Academy of Sciences).
Taxonomic treatment
Cylindrolobus motuoensis X.H.Jin & J.D.Ya, sp. nov.
urn:lsid:ipni.org:names:60479344-2
Figures 1, 3A
Diagnosis. Cylindrolobus motuoensis is similar to C. gloensis (Ormerod & Agrawala)
Schuit., Y.P. Ng & H.A. Pedersen, and C. foetidus (Aver.) Schuit., Y.P. Ng & H.A.
Pedersen in terms of morphological structure and shape of the owers (Hu et al. 2010,
Agrawala and Ormerod 2014, Ng et al. 2018). e new species can be distinguished
from C. gloensis by the smaller owers, elliptic and concave bracts, and ovate lip with
three keels, mid-lobe thickened and papillate on margin. e new species can be dis-
tinguished from C. foetidus with longer and wider leaves, dark red and elliptic oral
bracts, white owers and falcate-lanceolate lateral sepals.
Type. CHINA. Xizang Autonomous Region: Motuo, subtropical evergreen broad-
leaved forest, alt. 2000 m, 26 Feb 2017, Ji-Dong Ya, Cheng Liu, Hua-Jie He 17HT0073
(holotype: KUN!).
Additional specimen examined. CHINA. Xizang Autonomous Region: Motuo,
subtropical, evergreen broad-leaved forest, 26 Feb 2017, Xiao-Hua Jin, Ji-Dong Ya,
17HT1088 (paratype: KUN!)
Description. Epiphytic herb. Roots terete, slender, pubescent, ca.1.0‒1.5mm
thick. Rhizome creeping, to 3‒4 mm thick. Stem terete, slender, 3(2) leaved apically,
covered by close-tting sheaths, 18‒24 cm long, 3‒6 mm thick. Leaves ligulate-lan-
ceolate, acuminate, 10‒13 cm long, 1.5‒2.0 cm wide. Inorescences axillary, pubes-
cent, borne on near the apical of the stem, 2‒3 cm long, 2 owered; peduncle 1.0‒1.5
cm long; 2 sterile bracts, smaller, amplexicaul; rachis 0.2 cm long, oral bracts dark
red, elliptic, acute, concave, sparsely tomentum, 7 mm long, 3 mm wide. Flowers
white, sepal externally with brown tomentum, peduncle and ovary ca. 1.0‒1.5 cm
long, densely brown tomentum. Dorsal sepal lanceolate, acute, 5 veined, 11 mm long,
4 mm wide; lateral sepals falcate-lanceolate, acute, 5 veined, 9 mm long, 5 mm wide,
base adnate to column foot form a subglobose and obtuse mentum; petals lanceolate,
slightly oblique, acute, 3 veined, 10 mm long, 3 mm wide; labellum ovate in outline,
3-lobed, base hinged to the apex of the column foot, apex obtuse and emarginate,

Two new species of Cylindrolobus (Orchidaceae) from the eastern Himalayas 109
Figure 1. Cylindrolobus motuoensis X.H.Jin & J.D.Ya. A Plant B Inorescence C lateral view of ower
Dventral view of ower E front view of ower F adaxial sepals and petals G abaxial sepals and petals H lateral
view of column and lip I lateral view of column J front view of column K front view of labellum L lateral view
of labellum (rip cutting) M adaxial bract N abaxial bract O polar view of pollinarium Pventral view of pol-
linarium Q lateral view of pollinarium R adaxial anther cap S abaxial anther cap (Photographed by J.-D. Ya).
curved, c. 6 mm long, 3 mm wide; lateral lobes suberect, subovate, apex slightly intro-
vert; mid-lobe ligulate, ca. 3 × 3 mm, thickened and papillate on margin, apex emar-
ginate; disk with 3 keels, central keel longitudinal thickened, with orange papilla,
running from base to the tip of mid-lobe, lateral keels glabrous, running from base to
middle of mid-lobe. Column semiterete, ca. 4 mm long, broad winged at ventrally;
foot incurved, ca. 3.5 mm. Anther cap ovate, ca. 1 mm × 1 mm, pollinia 8, yellowish
white, compressed rectangular, anterior ca. 0.5 mm × 0.4 mm × 0.2 mm, posterior 4
smaller. Fl. February-March.
Etymology. e new species is named after Motuo, Xizang Autonomous Region
of China, where it was discovered in a subtropical evergreen broad-leaved forest.
Vernacular name. Mo Tuo Zhu Lan (墨脱柱兰).
Cylindrolobus glabriorus X.H.Jin & J.D.Ya, sp. nov.
urn:lsid:ipni.org:names:60479345-2
Figures 2, 3B
Diagnosis. Cylindrolobus glabriorus is similar to C. hegdei (Agrawala & H. J. Chowd-
hery) A. N. Rao and C. tenuicaulis (S. C. Chen & Z. H. Tsi) S. C. Chen & J. J.Wood

Ji-Dong Ya et al. / PhytoKeys 130: 107–113 (2019)
110
Figure 2. Cylindrolobus glabriorus X.H.Jin & J.D.Ya. A Plant B inorescence C ventral view of ower
D lateral view of ower E adaxial sepals and petals F abaxial sepals and petals G lateral view of column and
lip H front view of labellum I lateral view of labellum J ventral view of labellum K lateral view of column
L front view of column M adaxial bract N abaxial bract O lateral view of pollinarium P polar view of
pollinarium Q abaxial anther cap R adaxial anther cap (Photographed by J.D. Ya).
(Agrawala and Chowdhery 2008, Chen et al. 2009). e new species can be distin-
guished from C. hegdei by the longer and wider leaves, glabrous inorescence, smaller
and yellow owers, yellowish green and obovate bracts and reddish brown central
papillate keel of lip. It diers from C. tenuicaulis by having longer and wider leaves,
longer inorescence, yellowish green and obovate bracts, longer lip with three calli,
lateral margins of mid-lobe thickened and erect.
Type. MYANMAR. Kachin State: Putao Township, Hponkanrazi Wildlife Sanc-
tuary, subtropical, evergreen, broad-leaved, humid montane forest, alt. 2200 m, 12
Apr 2018, Xiao-Hua Jin, Ji-Dong Ya 18HT1618 (holotype: KUN!).
Additional specimen examined. CHINA. Xizang Autonomous Region: Motuo,
subtropical, evergreen broad-leaved forest, alt. 1796 m, 2 Apr 2019, Ji-Dong Ya, Cheng
Liu, 18HT2586 (paratype: KUN!). CHINA. Xizang Autonomous Region: Motuo,
subtropical, evergreen broad-leaved forest, alt. 1750 m, 7 Apr 2018, Hong Jiang, Wei-
ping Zhang, Zhou-dong Han 07336 (paratype: YAF!).
Description. Epiphytic herb. Roots terete, slender, pubescent, ca.0.8‒1.0 mm
thick. Rhizome inconspicuous. Stem clustered, terete, slender, 4-leaved apically, cov-
ered by close-tting sheaths, 13‒25 cm long, 3‒4 mm thick. Leaves lanceolate, acumi-
nate, 4.5‒6.5 cm long, 0.8‒1.5 cm wide. Inorescences axillary, glabrous, arising from
the apical of the stem, 1.3 cm long, 2-owered; peduncle 0.5 cm long; sterile bracts

Two new species of Cylindrolobus (Orchidaceae) from the eastern Himalayas 111
Figure 3. Holotype. A Cylindrolobus motuoensis X.H.Jin & J.D.Ya. B Cylindrolobus glabriorus X.H.Jin
& J.D.Ya.
1‒2, smaller. Flowers yellow, sepal externally reddish yellow, 7‒8mm long; oral
bracts yellowish green with red brown edges, obovate, mucronate, concave, glabrous,
4 mm long, 2.5 mm wide; peduncle and ovary ca. 4‒6 mm long. Dorsal sepal lan-
ceolate, obtuse, 3 veined, 6 mm long, 2 mm wide; lateral sepals falcate-ovate, obtuse,
3-veined, 5 mm long, 3.5 mm wide, base adnate to column foot form a subglobose
and obtuse mentum; petals oblong-ovate, slightly oblique at base, obtuse, 1 veined,
5mm long, 2mm wide; labellum oblong in outline, 3-lobed, base hinged to the apex
of the column foot, apex emarginate, ca.3.5 mm long, 1.5 mm wide; lateral lobes
suberect, subovate, apex slightly introvert, disk with 2 reddish brown calli; mid-lobe
sub-square, ca. 3.3 mm × 2 mm, lateral margins thickened and erect, with a central
papillate keel, reddish brown, ca. 0.5 mm high; apex emarginate. Column semiterete,
ca. 3.5 mm long, narrow winged at ventrally; rostellum triangle, 0.2 mm, a hook-like
protrusion under the stigma; foot incurved, ca. 4 mm; cap subrotund, ca. 0.6 mm
× 0.6 mm, papillate and protrude in front; pollinia 8, yellowish white, compressed
subrotund from the lateral view, anterior 4 ca. 0.2 mm × 0.2mm × 0.1mm, posterior
4 smaller. Fl. April-May.
Etymology. e specic epithet “glabriorus” refers to glabrous owers of this
new species.
Vernacular name. Zhong Mian Zhu Lan (中缅柱兰).

Ji-Dong Ya et al. / PhytoKeys 130: 107–113 (2019)
112
Discussion
e generic delimitation of Podochileae Ptzer has long been confused (Pridgeon et al.
2005, Ng et al. 2018). Recent molecular and morphological evidence reveals that Eria s.l.
should be split into 21 genera, including Cylindrolobus which is morphologically character-
ized by eshy and elongate stems, lateral inorescences, conspicuous and colorful bracts.
ese two new species are distributed in a narrow area in the border region be-
tween China and Myanmar. We found there are many populations of each species and
abundant individuals per population during our botanical expeditions. As the habitats
of these two species are in a remote location and the border area has restricted access,
the eect of human interference and climate change on them is little known. For the
time being, these two species are considered as Least Concern (LC) according to cur-
rent information on these species and the IUCN Red List category (IUCN 2012).
Located at the margin of Qinghai-Tibet Plateau, Motuo is famous for its vertical
vegetation system from tropical forest to permanent glacier with elevation approxi-
mately 7000 m, which allow the thriving and diversication of plant diversity. In ad-
dition, there are many biodiversity hotspots in the eastern Himalayas, e.g. the north
of Myanmar, however the species diversity of this region is poorly known. Hence, the
species diversity of these border regions requires solid investigations (Liu et al., 2019)
and timely conservation action plans in this region, in order to mitigate increasing
anthropogenic disturbance and destruction.
e two new species described here increased the members of Cylindrolobus in
China to seven species (Chen et al. 2009, Hu et al. 2010, Liu et al. 2013, Ng et al.
2018), the key to Chinese species of Cylindrolobus are developed here.
Key to Chinese species of Cylindrolobus
1 Stems stout, clavate .....................................................................................2
– Stems slender, terete .................................................................................... 4
2 Lip yellow ...................................................................................C. cristatus
– Lip lateral lobes with purple edges, mid-lobe with lighter purple edges
and patch ................................................................................................... 3
3 Inorescence glabrous, the lateral lobes bigger than mid-lobe .....C. clavicaulis
– Inorescence pubescent, the lateral lobes smaller than mid-lobe ...................
..............................................................................................C. marginatus
4 Inorescence glabrous .................................................................................5
– Inorescence pubescent ..............................................................................6
5 lip mid-lobe thickened and papillate on margin ......................C. tenuicaulis
– lip mid-lobe not thickened and smoothly on margin ............ C. glabriorus
6 Flowers yellow .............................................................................C. foetidus
– Flowers white ......................................................................... C. motuoensis

Two new species of Cylindrolobus (Orchidaceae) from the eastern Himalayas 113
Acknowledgements
We are grateful to Lian-Yi Li for his help with image processing; we convey our spe-
cial thanks to Forestry Bureau of Linzhi Prefecture for their kind help in the eld.
is research was supported by grants from the Chinese Scholarship Council (Grant
No. 201704910424), the National Natural Science Foundation of China (Grant No.
31670194), National Science & Technology Infrastructure and the Large-scale Sci-
entic Facilities of the Chinese Academy of Sciences (2017-LSFGBOWS-02), and
Southeast Asia Biodiversity Research Institute, Chinese Academy of Sciences (Y4Z-
K111B01 to X.H.J).
References
Agrawala DK, Chowdhery HJ (2008) A new species of Eria Lindl. (Orchidaceae) from
Arunachal Predesh, India. Phytotaxonomy 8: 8–12.
Agrawala DK, Ormerod P (2014) A new species of Eria (Orchidaceae) from India under the
section Cylindrolobus. Taiwania 59(3): 206–209. https://doi.org/10.6165/tai.2014.59.206
Chen SC, Lou YB, Vermeulen JJ (2009) Cylindrolobus Blume. In: Wu ZY, Raven PR, Hong DY
(Eds) Flora of China (Vol. 25). Science Press, Beijing & Missouri Botanical Garden Press,
St. Louis, 249–250.
Hu H, Jin XH, Sun Q, Sun XG (2010) A new record of Orchidaceae from China. Redai Yare-
dai Zhiwu Xuebao 18: 401–402.
IUCN (2012) IUCN Red List Categories and Criteria, Version 3.1. (2nd edn). IUCN, Gland.
Liu JJ, Baeten L, Verheyen K (2019) Biodiversity on International Borders Requires Solid In-
ventories. Bioscience 69(5): 322–323. https://doi.org/10.1093/biosci/biz029
Liu Q, Li JW, Yin JT (2013) Eria clavicaulis, a new record of Orchidaceae from Yunnan, China.
Guihuia 33(1): 70–71.
Ng YP, Schuiteman A, Pedersen HÆ, Petersen G, Watthana S, Seberg O, Pridgeon AM, Cribb
PJ, Chase MW, NG YP (2018) Phylogenetics and systematics of Eria and related genera
(Orchidaceae: Podochileae). Botanical Journal of the Linnean Society 186(2): 179–201.
https://doi.org/10.1093/botlinnean/box088
Ormerod P (2014) A Synopsis of Eria Lindl. Section Cylindrolobus (Blume) Lindl. (Orchidace-
ae: Eriinae) in Malesia. Harvard Papers in Botany 19(1): 77–95. https://doi.org/10.3100/
hpib.v19iss1.2014.n6
Pridgeon AM, Cribb PJ, Chase MW, Rasmussen FN (2005) Tribe Podochileae. In: Genera
Orchidacearum 4, Epidendroideae (part one). Oxford University Press, Oxford, 529‒596.