209
Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo
species om Guangxi, China
Zheng-Yang Niu1,2 , Lin Bai1,2, Yi-Hua Tong1,2 , Nian-He Xia1,2
1 S a e Key Labo a o y o Plan Di e si y and Special y C ops & Guangdong P o incial Key Labo a o y o Digi al Bo anical Ga den, Sou h China Bo anical
Ga den, Chinese Academy o Sciences, Guangzhou, 510650, China
2 Sou h China Na ional Bo anical Ga den, Chinese Academy o Sciences, Guangzhou, 510650, China
Co esponding au ho : Yi-Hua Tong ([email p o ec ed])
Copy igh : © Zheng-Yang Niu e al.
This is an open access a icle dis ibu ed unde
e ms o he C ea i e Commons A ibu ion
License (A ibu ion 4.0 In e na ional – CC BY 4.0).
Resea ch A icle
Abs ac
Based on mo phological and molecula phylogene ic e idence, we con i med ha some
bamboo collec ions om Guangxi, China, ep esen a new species o Indosasa. The new
species, named I. imb iligula a, is mo phologically simila o I. glab a a bu di e s by
ha ing in e nodes ha a e whi e s igose when young, and hollow wi hou o wi h a
li le clas ic pi h, culm buds iangula , culm lea shea hs abaxially sca e ed wi h u ed
b own se ae, culm lea au icles well de eloped, and culm lea ligule apex long imb ia e.
A de ailed desc ip ion, as well as wo colo pla es o his new species, is also p o ided.
Key wo ds: A undina ieae, mo phology, phylogeny, axonomy, h ee-b anched bamboos
In oduc ion
Indosasa McClu e was es ablished by F. A. McClu e (1940), wi h I. c assi lo a
designa ed as i s gene ic ype. I belongs o he sub ibe A undina iinae o he
ibe A undina ieae (Poaceae, Bambusoideae) (Zhang e al. 2020) and con ains
17 species mainly dis ibu ed in China (Fujian, Hunan, Guangdong, Guangxi,
Guizhou, Yunnan), Vie nam, and Laos (Zhu and Zhao 1996; Zhu and S aple on
2006; Vo on so a e al. 2016; Niu e al. 2021, 2022, 2025a). I is diagnosed
by lep omo ph (monopodial) hizomes, di use culms, s ongly aised culm su-
p a-nodal idges, pseudospikele s, six s amens, and h ee s igmas pe lo e
(McClu e 1940; Chao and Chu 1983; Zhu and Zhao 1996; Xue e al. 2003; Zhu
and S aple on 2006; Yi e al. 2008; Xia and Lin 2009; Xia e al. 2016; Shi e al.
2021). Howe e , some ecen phylogenomic s udies sugges ed ha Indosasa
sensu la o (s.l.) is non-monophyle ic (Guo e al. 2021; Niu 2025). Indosasa sen-
su s ic o (s.s.) is de ined by he possession o s ongly aised and asymme i-
cally swollen b anch sup a-nodal idges, usually 4–9 oliage lea es pe ul ima e
b anch, and he ai s men ioned abo e (Niu 2025). The newly de ined Indosasa
s.s. has only eigh species, and i s dis ibu ion is limi ed o Guangxi, Yunnan,
and Sou h Guizhou o China, No h Vie nam, and No h Laos (Niu 2025).
Du ing wo ield in es iga ions in Fangchenggang Ci y, Guangxi, we encoun-
e ed a unning bamboo ha does no i he desc ip ion o any known species.
Academic edi o : Wei Lim Goh
Recei ed:
6 Augus 2025
Accep ed:
15 Sep embe 2025
Published:
4 No embe 2025
Ci a ion: Niu Z-Y, Bai L, Tong Y-H, Xia
N-H (2025) Indosasa imb iligula a
(Poaceae, Bambusoideae), a new
bamboo species om Guangxi, China.
Phy oKeys 265: 209–221. h ps://doi.
o g/10.3897/phy okeys.265.167921
Phy oKeys 265: 209–221 (2025)
DOI: 10.3897/phy okeys.265.167921
210
Phy oKeys 265: 209–221 (2025), DOI: 10.3897/phy okeys.265.167921
Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
Howe e , some ai s, such as s ongly aised culm sup a-nodal idges, s ongly
aised and asymme ically swollen b anch sup a-nodal idges, and he b anch
complemen wi h h ee b anches pe mid-culm node, ma ch well wi h hose
diagnos ic o Indosasa s.s. A e compa ison wi h all he p e iously eco ded
species o Indosasa in na ional and local lo as (Chao and Chu 1983; Zhu and
Zhao 1996; Xue e al. 2003; Zhu and S aple on 2006; Yi e al. 2008; Xia and Lin
2009; Xia e al. 2016; Shi e al. 2021), as well as he monog aph o Indosasa
(Niu 2025), we ound ha his species is mos simila o I. glab a a C.D.Chu
& C.S.Chao. In o de o cla i y he axonomic iden i y o his bamboo, we con-
duc ed phylogene ic and mo phological s udies. Finally, we con i med ha his
bamboo is new o science based on mo phological and molecula e idence.
Ma e ials and me hods
Mo phological s udy
Mo phological compa isons be ween his new species and mo phologically
simila species we e conduc ed based on li ing plan s in he ield, specimens,
p o ologues, and desc ip ions om lo as (Chao and Chu 1983; Zhu and Zhao
1996; Zhu and S aple on 2006; Xia e al. 2016; Niu 2025). Some de ailed cha -
ac e s, such as indumen um, we e obse ed wi h a s e eomic oscope (Msho
MZ101, Guangzhou Mic o-sho Technology Co., L d., Guangzhou, China). Mea-
su emen s we e aken using a ule o mic ome e . Te minology ollows Mc-
Clu e (1940), Li e al. (2006), and Been je (2016).
Taxon sampling, DNA ex ac ion, and sequencing
To asce ain he phylogene ic posi ion o his new species, we conduc ed phy-
logene ic analyses based on nuclea single-copy o hologous genes (SOGs).
Acco ding o he mos ecen phylogene ic amewo k o h ee-b anched
bamboos (Niu e al. 2025b), we selec ed 22 samples ep esen ing 21 bam-
boo species belonging o eigh gene a. Speci ically, he ing oup om he ibe
A undina ieae con ained six species o Indosasa, h ee species o Acidosasa
B.M.Yang, h ee species o Oligos achyum Z.P.Wang & G.H.Ye, h ee species o
Pseudosasa Makino ex Nakai, wo species o Pleioblas us Nakai, wo species
o Sinobambusa Makino ex Nakai, and one species o Indocalamus Nakai. Bam-
busa ulga is Nees om he ibe Bambuseae was chosen as he ou g oup.
Sample numbe s and hei co esponding ouche in o ma ion a e lis ed in
Suppl. ma e ial 1: able S1.
Fo DNA ex ac ions, young lea es we e collec ed in he ield and d ied wi h
silica gel. To al genomic DNA was ex ac ed om he d ied lea es using he
Rapid Plus DNA Lib P ep Ki o Illumina (RK2008) (ABclonal, Wobu n, USA)
and shea ed (1 μg DNA pe sample) using a Co a is M220 ul asonica o (Co-
a is, Wobu n, USA). PCR p oduc s we e pu i ied using he AMPu e XP sys em
(Be e ly, USA). Lib a y quali y was assessed on he Agilen 5400 sys em (Agi-
len , USA), and DNA quan i ica ion was pe o med by quan i a i e polyme ase
chain eac ion (qPCR). The quali ied pai ed-end lib a y was pooled using he
NEBNex ® Ul aTM DNA Lib a y P ep Ki and sequenced on he No aSeq 6000
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Phy oKeys 265: 209–221 (2025), DOI: 10.3897/phy okeys.265.167921
Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
pla o m wi h he PE150 s a egy. A e il a ion o adap e s and low-quali y
eads using Fas p so wa e . 0.23.2 (Chen e al. 2018), we ob ained a leas 40
Gb o deep genome skimming da a.
Ta ge nuclea single-copy o hologous genes cap u e
Fo nuclea gene eco e y, we used he p o ein-coding sequences o six p e i-
ously published bamboo genomes – Dend ocalamus la i lo us Mun o (Zheng e
al. 2022), Phyllos achys edulis (Ca iè e) J.Houz. (Zhao e al. 2018), Bonia am-
plexicaulis (L.C.Chia, H.L.Fung & Y.L.Yang) N.H.Xia, Guadua angus i olia Kun h,
Oly a la i olia L., and Raddia guianensis (B ongn.) Hi chc. (Guo e al. 2019) – o
iden i y 737 common nuclea single-copy o hologous genes (SOGs) using O -
ho inde . 2.5.4 (Emms and Kelly 2019). We eco e ed pu a i e SOGs using
HybPipe . 2.0.1 (Johnson e al. 2016). In his pipeline, we employed BWA .
0.7.17 (Li and Du bin 2009) o map il e ed eads o each speci ied SOG. We
hen de no o assembled eads and mapped hem o each SOG in o con igs us-
ing SPAdes . 3.15.0 (Banke ich e al. 2012). We aligned he assembled con igs
o he e e ence SOG da ase and used he Py hon sc ip ‘ e ie e_sequences.
py’ o eco e 737 pu a i e o hologs o each sample. Howe e , because ou
samples a e polyploid (Guo e al. 2019), some so-called SOGs may ha e mul i-
ple copies. We he e o e used he Py hon sc ip ‘pa alog_ e ie e .py’ o de ec
and emo e po en ial pa alogs. A e his s ep, we e ained 479 SOGs.
Alignmen and phylogene ic in e ence
We aligned he 479 SOGs using MAFFT . 7.505 (Ka oh and S andley 2013) in
Geneious . 9.1.4 (Kea se e al. 2012). We immed each single-gene ma ix
using imAl . 1.4 (Sal ado e al. 2009) wi h de aul se ings. We hen emo ed
nuclea genes wi h leng hs sho e han 300 bp o wi h >50% missing da a. The
inal nuclea da ase used o phylogene ic analyses included 465 SOGs. All
SOG alignmen s can be ound in Suppl. ma e ial 1.
We used a mul i-species coalescen -based me hod o nuclea gene-based
phylogene ic in e ence. We i s in e ed indi idual ML ees using RAxML .
8.2.12 (S ama akis 2014) o each nuclea gene and es ima ed b anch suppo
using boo s apping analysis (Felsens ein 1985) wi h 500 eplica es, all unde
he GTRGAMMAI model. To imp o e coalescen analysis accu acy (Zhang e
al. 2018; Cai e al. 2021), we collapsed b anches wi h suppo alues below
30% using Newick U ili ies . 1.6.0 (Junie and Zdobno 2010). We used he e-
sul ing collapsed indi idual gene ees and co esponding boo s apped ees
o in e he species ee based on he mul i-locus boo s apping (MLB) me hod
in ASTRAL-III (Seo 2008; Zhang e al. 2018). We hen c ea ed 500 coalescen
boo s ap eplica es, each consis ing o 465 gene ees (one ee pe gene,
andomly sampled om boo s apping ees wi hou eplacemen ) o qua e
analysis. The inal MLB species ee was in e ed om he 500 esul ing “spe-
cies” ees. MLB b anch boo s ap alues (BS) we e calcula ed based on he
equency wi h which b anches appea ed ac oss he 500 esul ing “species”
ees using he g eedy consensus me hod (So o Gomez e al. 2019). We con-
side ed BS >70% as s ong suppo .
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Phy oKeys 265: 209–221 (2025), DOI: 10.3897/phy okeys.265.167921
Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
Resul s
Ou nuclea SOG-based MLB species ee s ongly suppo ed ha he new species
is a membe o Indosasa s.s. and is closely ela ed o I. glab a a (BS = 100) (Fig. 1).
Mo phological compa ison e ealed ha he new species is mo phologically
simila o I. glab a a in ha ing small culms ha a e 2–4 m high and 0.5–2 cm
in diam., na ow and long iangula pape y culm lea shea hs, and linea -lance-
ola e culm lea blades, whe eas he o he Indosasa species a e usually cha ac-
e ized by ela i ely la ge culms, lea he y culm lea shea hs, and b oad lance-
ola e o o a e culm lea blades. The new species can be easily dis inguished
om I. glab a a by ha ing iangula ( s. obla e) culm buds, whi e s igose ( s.
glab ous) young culm in e nodes, wi hou pi h o wi h sligh ly clas ic pi h ( s.
lamella e pi h), abaxial su ace o culm lea shea h wi h sca e ed clumps o
b own se ae and base o culm lea shea h wi h dense b own se ae ( s. glab ous
culm lea shea h), well-de eloped ( s. unde eloped) culm lea au icles and o al
se ae, and culm lea ligule wi h long imb iae ( s. glab ous) (Table 1; Figs 2–4).
Figu e 1. The mul i-locus boo s apping ASTRAL species ee shows he phylogene ic posi ion o Indosasa imb iligula a,
which is econciled by coalescence o 465 single-copy o hologous nuclea gene ees a e collapsing b anches wi h
suppo alues <30%. BS suppo alues below 70% a e ep esen ed by a slash.
Sinobambusa oo sik a
. den a a
Oligos achyum lanceola um
Indosasa imb iligula a
Indocalamus mac ophyllus
Pleioblas us macula us
Indosasa singulispicula
Pseudosasa japonica
Indosasa ingens
Oligos achyum scab i lo um
Acidosasa glauca
Indosasa glab a a BH64
Indosasa c assi lo a
Acidosasa pu pu ea
Pseudosasa hindsii
Pseudosasa amabilis
Indosasa sinica
Indosasa glab a a LX181
Oligos achyum sulca um
Pleioblas us iangula us
Acidosasa enus a
Sinobambusa oo sik
Bambusa ulga is
100
98
100
86
86
100
100
100
73
/
100
100
100
100
100
100
100
100
82
100
ex emely sho b anch
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Phy oKeys 265: 209–221 (2025), DOI: 10.3897/phy okeys.265.167921
Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
Discussion
Al hough ecen phylogene ic s udies based on plas id and nuclea sequences
con i med ha Indosasa s.l. is non-monophyle ic (Ma e al. 2017; Guo e al.
2021; Niu 2025), his new species is undoub edly a membe o Indosasa s.s.
based on bo h mo phological and molecula e idence (Figs 1–4; Table 1). No
only do i s mo phological cha ac e s ma ch well wi h hose o Indosasa s.s.,
bu he phylogene ic analysis also showed ha i and I. glab a a o m a mono-
phyle ic clade wi h he ype species o Indosasa, iz., I. c assi lo a. Fu he com-
pa ison wi h mo phologically simila species con i med ha i is a dis inc new
species, which is desc ibed and illus a ed below.
Taxonomic ea men
Indosasa imb iligula a N.H.Xia, Z.Y.Niu & Y.H.Tong, sp. no .
u n:lsid:ipni.o g:names:77371342-1
Figs 2–4
Type. China • Guangxi Zhuang Au onomous Region: Fangchenggang Ci y, Na-
liang Town, Gaolin Village; 21°37'48"N, 107°40'57"E; al . 391 m; 17 Ap il 2025;
L. Bai & H. Y. Li BLSC-25041501 (holo ype: IBSC!).
Diagnosis. Indosasa imb iligula a esembles I. glab a a bu di e s om he
la e in ha ing whi e s igose in e nodes when young, hollow in e nodes wi h-
ou pi h o wi h a li le clas ic pi h, abaxial su ace o culm lea shea hs sca -
e ed wi h u ed b own se ae, well-de eloped culm lea au icles, and culm lea
ligule apex wi h long imb iae.
Desc ip ion. Rhizomes lep omo ph. Culms di use, e ec , some imes lexuose,
2–4 m all and 0.5–1.5 cm in diame e ; in e nodes la ened on b anching side,
wi h wo longi udinal idges and h ee g oo es abo e b anching poin s along he
b anching side, 30–50 cm long, ini ially g een o da k g een, yellow-g een when
aged, whi e s igose when young, glab escen when old, whi e powde y only a
in anodal egions; walls 3–4 mm hick, ca i y hollow wi hou pi h o wi h sligh ly
Table 1. Mo phological compa ison o Indosasa imb iligula a and I. glab a a.
Cha ac e s I. imb iligula a I. glab a a
Young culm
P ima y buds T iangula Obla e
Su ace o in e nodes Whi e s igose Glab ous
Ca i y pi h Nea ly absen Lamella e
Culm lea
Abaxial su ace o shea hs Sca e ed wi h u ed b own se ae Glab ous
Base o abaxial su ace o
shea hs
Densely b own se ose Glab ous
Au icles Small, ca. 0.5 × 1 mm Unde eloped
O al se ae De eloped, 2–10 mm long Unde eloped
Apex o ligules Fimb ia e Glab ous
Blade shape Linea o linea -lanceola e Na ow lanceola e o
lanceola e
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Phy oKeys 265: 209–221 (2025), DOI: 10.3897/phy okeys.265.167921
Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
Figu e 2. Indosasa imb iligula a N.H.Xia, Z.Y.Niu & Y.H.Tong. A. Habi ; B. Old culm; C. Culm bud; D. B anch complemen
wi h h ee b anches a culm node; E. Po ion o culm lea showing lea blade; F. Po ion o culm lea showing shea h base;
G. Culm pi h. Scale ba s: 5 cm (G).
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Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
Figu e 3. Indosasa imb iligula a N.H.Xia, Z.Y.Niu & Y.H.Tong. A. B anch complemen , showing s ongly aised and asym-
me ically swollen b anch sup a-nodal idges; B. Foliage lea y b anchle s; C. Ul ima e oliage lea y b anchle ; D. Po ion
o oliage lea y b anchle showing au icles and o al se ae; E. Po ion o culm lea , showing culm lea blade; F. Culm lea
ligule wi h long imb iae; G. Culm lea shea h base. Scale ba s: 5 cm (A); 10 cm (C); 5 mm (F); 1 cm (D, E, G).
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Phy oKeys 265: 209–221 (2025), DOI: 10.3897/phy okeys.265.167921
Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
Figu e 4. Indosasa imb iligula a N.H.Xia, Z.Y.Niu & Y.H.Tong. A. Culm lea shea h; B. Po ion o culm, showing lea blade,
node, and in e node; C. Culm node, showing culm bud and shea h sca ; D. B anch complemen wi h h ee b anches a
culm node, showing s ongly aised and asymme ically swollen b anch sup a-nodal idges; E. Ul ima e oliage lea y
b anchle . Scale ba s: 2 cm (A–E).
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Zheng-Yang Niu e al.: Indosasa imb iligula a (Poaceae, Bambusoideae), a new bamboo species om Guangxi, China
clas ic pi h; sup a-nodal idges s ongly aised, shea h sca s p ominen , wi h a
co ky ing and densely b own se ose when young, glab escen when old, wi h
pe sis en emains o shea h base. B anch sup a-nodal idges s ongly aised
and asymme ically swollen. P ima y buds soli a y, iangula , yellowish g een,
no sunken in o culm, ma gin densely cilia e. B anch complemen wi h h ee
b anches a each culm node. Culm lea shea hs ini ially g een wi h small pu ple
do s, mo e so on he ma ginal pa , u ning o s aw when old, a dily deciduous,
na ow and long iangula , pape y, abaxially sca e ed wi h u ed b own se ae,
densely b own se ose a base, ma gins densely cilia e; au icles small, o a e o
iangula , ca. 1 × 0.5 mm; o al se ae well-de eloped, many, s aigh o sligh ly
o uous, 2–10 mm long; ligules a cua e, ca. 2 mm all, abaxially pube ulen , apex
long imb ia e, imb iae many, s aigh o sligh ly o uous, 3–7 mm long; blades
e lexed, linea o linea -lanceola e, 0.8–3 × 0.1–0.3 cm, 3/50–6/50 as long as
shea h, apex acumina e, base na owed, adaxially spa sely b own se ae, abax-
ially glab ous. Foliage lea es 4–7 pe ul ima e b anchle ; shea hs 3.5–6.5 cm
long, glab ous, longi udinal ibs conspicuous when d y; au icles well-de eloped,
o a e o iangula , 3–5 × 1–3 mm; o al se ae many, s aigh o sligh ly o uous,
3–20mm long; ligules sho , unca e, 0.5–1mm all, abaxially pubescen ; blades
lanceola e, pape y, 9.5–24 × 1.5–3.8 cm, apex acumina e, base cunea e o widely
cunea e, glab ous on bo h sides, one ma gin se ula e, o he ma gin en i e, sec-
onda y eins 5–8 pai s, ans e se einle s conspicuous. In lo escence unknown.
Phenology. New shoo s om Ap il o June.
Dis ibu ion and habi a . This new species has been ound only in i s ype lo-
cali y so a . I usually occu s on moun ain slopes nea oadsides and s eams.
E ymology. The speci ic epi he e e s o he imb ia e culm lea ligule o his
species, which is a ely seen in o he Indosasa species. I s Chinese name is
gi en as 流苏大节竹 [liú sū dà jié zhú].
Addi ional specimens examined. China • Guangxi: Fangchenggang Ci y, Na-
liang Town, Gaolin Village; 21°37'34"N, 107°41'8''E; al . 443 m; 15 June 2025; Z.
Y. Niu, NZY297 (IBSC).
Local usage. Old culms a e used o ences.
Acknowledgmen s
We a e g a e ul o Ms. Hong-Yan Li (Sou h China Bo anical Ga den, Chinese
Academy o Sciences) o he assis ance du ing he ieldwo k and o M . Ding-
Han Cui (Sou h China Bo anical Ga den, Chinese Academy o Sciences) o he
line d awing.
Addi ional in o ma ion
Con lic o in e es
The au ho s ha e decla ed ha no compe ing in e es s exis .
E hical s a emen
No e hical s a emen was epo ed.
Use o AI
No use o AI was epo ed.
