KEW BULLETIN VOL. 63: 669–673 (2008)
Phuphanochloa, a new bamboo genus (Poaceae: Bambusoideae)
from Thailand
Sarawood Sungkaew1,2, Atchara Teerawatananon1,3, John A. N. Parnell1, Chris M. A. Stapleton4
& Trevor R. Hodkinson1
Summary. A new monotypic bamboo genus Phuphanochloa (Poaceae: Bambusoideae) from north-eastern Thailand is
described, together with a new species, P. speciosa.
Key Words. Bambuseae, Bambusoideae, Phuphanochloa, Poaceae, Thailand.
Introduction
During field work for the revision of the genus
Dendrocalamus for the Flora of Thailand, vegetative and
flowering specimens of a distinctive new bamboo
were found. This bamboo was included in a comprehensive DNA sequence analysis (Sungkaew et al. in
press), and can now be described as a new genus
Phuphanochloa, on the basis of morphology and
molecular phylogenetics.
Phuphanochloa
Phuphanochloa Sungkaew & Teerawat., gen. nov.
Poacearum-Bambusoidearum rhizomatibus sympodialibus
brevicollibus. Culmus unicaespitosus erectus. Inflorescentia indeterminata; spicula 1 – 4 gluma, 7 – 9 flores et
1 – 2 flores terminales vestigiales ferenti, internodio
basalis rachillae longo, 3 lodiculis, staminibus filamentis
liberis 6, ovario apice pubescenti, stylo solitarium,
stigmatibus 3. Typus: P. speciosa Sungkaew & Teerawat.
Rhizomes short-necked pachymorph. Culms unicaespitose, straight and erect; internodes smooth; nodes
slightly swollen. Branch bud solitary at each node,
developing into several branches, the primary one
dominant. Culm sheaths deciduous, occasionally tardily
deciduous at basal nodes, coriaceous; blades spreading
to deflexed; auricles absent, or inconspicuous rims,
margins entire, occasionally slightly wavy, glabrous;
ligule short, margin toothed to bristly. Leafy branchlets
bearing 6 – 8 moderate sized leaves. Leaves hairy
underneath, pseudo-petioles short; sheaths hairy;
auricles absent or of tiny rims bearing oral setae; ligule
short, margin toothed. Inflorescences indeterminate,
bracteate, borne on leafless branches; pseudospikelets
clustered in spicate mass, 0 – few small empty bracts,
2 – 4 bracts subtending prophyllate buds; internodes
glabrous.
Spikelets large, ovate to elliptic in outline, purple,
laterally compressed; glumes 1 – 4, shorter than the
lowest lemma, coriaceous or somewhat rigid; fertile
florets 7 – 9, with 1 – 2 terminal vestigial florets,
shorter than fertile florets; rachilla internodes between florets (from the second floret upwards) short,
disarticulating below each floret, rachilla internode
distal to the lowermost floret frequently longer;
lemmas chartaceous, the basal ones distally more
rigid; paleas 2-keeled; lodicules usually 3; stamens 6,
filaments free; ovary hairy at the top, style more or less
hairy and flattened upwards, stigma 3, slightly plumose. Caryopsis hirsute at apex, beaked with the
persistent base of the style.
Phuphanochloa can be included in subtribe Bambusinae
in the classification of Soderstrom & Ellis (1987). It
shares several characters in common with Bambusa,
Accepted for publication October 2008.
1
Department of Botany, School of Natural Sciences, Trinity College Dublin, University of Dublin, Dublin 2, Ireland.
2
Department of Forest Biology, Faculty of Forestry, Kasetsart University, Bangkok, Thailand.
3
Thailand Natural History Museum, National Science Museum, Techno polis, Pathum Thani, Thailand.
4
Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AB, UK.
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2008
KEW BULLETIN VOL. 63(4)
670
including similar vegetative appearance and branching, indeterminate spicate inflorescences with six
stamens and free filaments. There are also few glumes,
many (7 – 9) fertile florets which have variably
elongated rachilla internodes that disarticulate below
each floret. However, in Phuphanochloa the spikelets
usually break up at maturity in one of two ways (both
of which are usually present on any single individual);
either the spikelet totally breaks up above the glume(s)
leaving only the elongated rachilla internode (0.5 –
2 cm long), or it breaks up above the glume(s) and
above the lowest floret leaving the upper part of the
elongated rachilla internode (to 0.5 cm long) along
with the glume(s) and intact lowest floret (this is not
the case in Bambusa). In the length of the basal rachilla
internodes, the genus shows similarities to Bonia
Balansa from S China (Xia & Stapleton 2006), but
the spikelets of Phuphanochloa are broader, and culm
branching is not solitary. In addition, in Bambusa
there are 1 – 3 distinctly plumose stigmas while in
Phuphanochloa there are usually three, and they are
only slightly plumose. Phuphanochloa can be easily
distinguished from Dendrocalamus by its elongated
and disarticulating rachilla internodes (very short
and not disarticulating in Dendrocalamus) and the less
globose inflorescences. Phuphanochloa differs from
Gigantochloa, in having free filaments instead of fused
filaments. The differences between these four genera
and Phuphanochloa are summarised in Table 1.
The results from combined analysis of five plastid
DNA regions (trnL intron, trnL-F intergenic spacer,
atpB-rbcL intergenic spacer, rps16 intron, and matK
gene region, Fig. 1) (Sungkaew et al. in press) show
that Phuphanochloa is sister to a group comprising
Bambusa species (B. beecheyana Munro, B. emeiensis L. C.
Chia & H. L. Fung (as Neosinocalamus affinis in the
tree), B. malingensis McClure and B. oldhamii Munro)
with parsimony bootstrap support of 86% and a
Bayesian posterior probability (PP) value of 1.00.
These four species of Bambusa group together with
bootstrap support of 80% (1.00PP). They represent
three of the four subgenera of Bambusa according
to Xia et al. (2006). B. malingensis represents subg.
Bambusa; B. beecheyana and B. oldhamii represent
subg. Dendrocalamopsis; and B. emeiensis represents
subg. Lingnania. The results of the molecular analysis
Table 1. Comparative table of habit and morphological characters between Bambusa, Bonia, Dendrocalamus, Gigantochloa and
Phuphanochloa.
Characters
Bambusa
Bonia
Dendrocalamus
Gigantochloa
Phuphanochloa
Habit
Branch number at
mid-culm branch
complement
Culm-sheath auricles;
oral setae/ Culmsheath blade
usually erect
several
scrambling
single
usually erect
several
usually erect
several
usually erect
several
usually
conspicuous;
always present/
usually erect
conspicuous, but
often small
to absent;
present or
absent/erect
to deflexed
usually absent
or small;
usually absent,
occasionally
present/erect
to deflexed
usually absent or
small; always
absent/spreading
to deflexed,
never erect
Number of glumes
per spikelet
Number of
fertile florets
per spikelet
Rachilla internodes
0–3
usually conspicuous,
occasionally
inconspicuous or
small; usually
present, occasionally
absent/erect to
deflexed
0–2
(1 –) 2 – 4 (– 9)
1–5
1–4
2 – 13
3–9
1–8
(1 –) 2 – 5
7–9
distinct and
disarticulating
typically (1 –) 3,
plumose
typically free
distinct and
disarticulating
typically 3, plumose
obscure and not
disarticulating
typically 1 (– 3),
plumose
typically free
distinct and
disarticulating
typically 3, slightly
plumose
typically free
either breaking
up above the
glume(s) or
between the
florets
unknown
obscure and not
disarticulating
typically 1,
plumose
always fused into
a firm tube
usually breaking
up above
the glume(s)
Stigma
Filaments
Breaking up at
maturity of
spikelets
typically free
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2008
usually breaking
up above the
glume(s)
usually breaking
up in one of
two ways (both
of which are
usually present
on any single
individual);
either above the
glume(s) or
above the lowest
floret
PHUPHANOCHLOA, A NEW BAMBOO GENUS
671
Fig. 1. Part of a multigene region phylogenetic tree (trnL intron, trnL-F intergenic spacer, atpB-rbcL intergenic spacer, rps16 intron,
and matK gene region) of Bambusoideae (from Sungkaew et al. in press). Values above branches represent branch length, values
below branches represent parsimony bootstrap support and bracketed numbers represent Bayesian posterior probability value (PP).
Phuphanochloa is sister to a group of Bambusa species (B. beecheyana Munro, Neosinocalamus affinis (Rendle) P. C. Keng (=B.
emeiensis L. C. Chia & H. L. Fung), B. malingensis McClure and B. oldhamii Munro) and does not group closely with another
two Bambusa species (B. bambos (L.) Voss and B. tulda Roxb.).
show that Phuphanochloa cannot be included in any of
these three subgenera. Phuphanochloa cannot be
considered as a member of the fourth subgenus of
Bambusa (subg. Leleba) either. This is because subg.
Leleba typically has a broad culm-sheath blade (base
of culm-sheath blade ½ – ¾ width of sheath apex)
as remarked by Xia et al. (2006); it is much smaller
than ½ in Phuphanochloa. Its culm-sheath blade, in
contrast, is more similar to those of Dendrocalamus or
Gigantochloa. In addition, subg. Leleba has a thick
papery culm sheath with a deciduous culm-sheath blade
(Xia et al. 2006) while Phuphanochloa has a coriaceous
culm sheath with a persistent culm-sheath blade.
Phuphanochloa is therefore distinct from Bambusa.
The genus is named after Phu Phan National Park,
in Sakon Nakhon Province, north-eastern Thailand,
where the species Phuphanochloa speciosa grows.
Phuphanochloa speciosa Sungkaew & Teerawat., sp.
nov. Culmi unicaespitosi, compacti, c. 5 – 10 m longi
et 3 – 5 cm diametri, internodia 25 – 30 cm longa;
vaginis culmi pubescens; laminis foliorum pubescens
infra; specula purpura, 1 – 4 gluma, 7 – 9 flores et 1 –
2 flores terminales vestigiales ferenti, lemmata hirsuta
dorsi prope basin; styli plus minusve pubescens,
stigmatum 3 parum plumosus. Typus: Thailand, Sungkaew & Teerawatananon 472 (holotypus TCD!; isotypi
BKF!, K!, Herbarium of Faculty of Forestry, Kasetsart
University!, Herbarium of Thailand Natural History
Museum, National Science Museum!).
Rhizomes short-necked pachymorph. Culms self-supporting, unicaespitose in a dense clump, straight and
erect, about 5 – 10 m long, 3 – 5 cm in diam., walls
0.5 – 1 cm thick, smaller culms sometimes solid at
basal internodes, culm tips more or less arched
outwards; internodes 25 – 30 cm long; young culms
glabrous, white-waxy, mature culms, green; nodes
slightly swollen, all nodes without verticils of roots.
Branches developing at all nodes to near base, several
branches at each node, the primary one dominant,
without aerial roots. Culm sheaths deciduous, occasionally tardily deciduous at basal nodes, coriaceous, 20 –
25 cm long by 12 – 17 cm wide, top obtuse, scattered
with short pale hairs on the back, sometimes with a
slight distal abaxial wrinkle; blades lanceolate, spreading to deflexed, 2 – 3.5 cm long, about 0.5 – 1 cm wide
near the base, hairy at the adaxial base; auricles
absent, or small rims, about 1 mm high, margins
usually entire, occasionally slightly wavy, glabrous;
ligule 2 – 3 mm high, margin toothed to bristly,
bristles 2 – 5 mm long. Leaves 6 – 8 per branchlet; leafblades 10 – 15 cm long by 1 – 1.3 cm wide, abaxially
hairy, apex acuminate, base acute, pseudo-petioles
0.5 – 2 mm long, secondary veins in 3 – 4 pairs,
intermediate veins 5 – 6; auricles absent or of tiny rims
bearing oral setae 1 – 3 mm long; ligule 1 – 2 mm
high, apex obtuse, margin toothed; sheaths 4 – 5 cm
long, hairy. Inflorescences indeterminate, bracteate,
borne on leafless branches; pseudospikelets clustered
in spicate mass, 2 – 4 cm in diam., 0 – few small empty
bracts, 2 – 4 bracts subtending prophyllate buds;
internodes 2 – 7 cm long, glabrous. Spikelets ovate to
elliptic (from the second floret upwards), 1 – 2 cm
long by 0.5 – 1 cm wide, purple, laterally compressed;
glumes 1 – 4, shorter than the lowest lemma,
coriaceous or somewhat rigid, 11 – 17-nerved; fertile
florets 7 – 9, with 1 – 2 terminal vestigial florets,
shorter than fertile florets; rachilla internodes be© The Board of Trustees of the Royal Botanic Gardens, Kew, 2008
672
KEW BULLETIN VOL. 63(4)
Fig. 2. Phuphanochloa speciosa. A culm shoot; B culm sheath; C leafy branch; D flowering branch; E flowering branch, showing 2
mature pseudospikelets (the one on the left with floret parts fallen); F a pseudospikelet, showing (from the base) an empty bract, 3
bracts subtending prophyllated buds (gemmiferous bracts), 2 glumes, 9 florets with a hidden vestigial floret; G glumes; H lemmas,
showing ventral view (left) and dorsal view (right); J paleas, intermediates are found; K terminal vestigial florets; L pistil; M stamens.
A – C from Sungkaew & Teerawatananon 191; D – M from Sungkaew & Teerawatananon 472. DRAWN BY A. TEERAWATANANON.
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2008
PHUPHANOCHLOA, A NEW BAMBOO GENUS
tween florets (from the second floret upwards) short,
1 – 1.5 mm long, disarticulating below each floret,
rachilla internode distal to the lowermost floret
frequently longer, to 0.5 cm; lemmas chartaceous,
the basal ones distally more rigid, 6 – 11.5 mm long,
with a tuft of brown hairs on the back near the base,
13 – 21-nerved, apex acute; paleas coriaceous, 5 –
10 mm long, 2-keeled on the back, slightly winged,
wings 0.5 – 0.7 mm wide, keels and margins ciliate, the
uppermost slightly winged, keeled but only sparsely or
not ciliate, outside glabrous, inside scattered with
short and minute hairs, apex acute or slightly cleft,
2 – 3-nerved between keels, 1 – 2-nerved between keel
and margin; lodicules usually 3, hyaline, fringed with
fine cilia, distally shortly pubescent; stamens 6, filaments
free, anthers 3 – 4 mm long, yellow, tips shortly
apiculate; ovary ovate-umbonate, summit hairy, style
more or less hairy and flattened upwards, stigma 3, flat
and thin, slightly plumose. Caryopsis oblong-elliptic, 5 –
6 mm long, apex hirsute, beaked with the persistent
base of the style, furrowed on one side. Fig. 2.
DISTRIBUTION. Endemic to north-eastern Thailand.
THAILAND. NE21, Sakhon Nakhon: Phu Phan National
Park, base of Nang Mern cliff, sterile, 14 Aug. 2004,
Sungkaew & Teerawatananon 191 (TCD, Herbarium of
Faculty of Forestry, Kasetsart University; Herbarium of
Thailand Natural History Museum, National Science
Museum), fertile, 11 April 2005, Sungkaew & Teerawatananon 472 (holotype TCD; isotypes BKF, K, Herbarium
of Faculty of Forestry, Kasetsart University, Herbarium
of Thailand Natural History Museum, National Science
Museum), fertile, 20 March 2006, Sungkaew & Teerawatananon 884 (TCD, Herbarium of Faculty of Forestry,
Kasetsart University, Herbarium of Thailand Natural
History Museum, National Science Museum).
HABITAT. Deciduous dipterocarp forest; c. 500 m.
CONSERVATION STATUS. Uncertain but probably rare;
known from only a single locality.
NOTES. Spikelets break up at maturity in one of two
ways (both of which are usually present on any single
673
individual); either the spikelet totally breaks up above
the glume(s) leaving only the elongated rachilla
internode (0.5 – 2 cm long), or it breaks up above
the glume(s) and above the lowest floret leaving the
upper part of the elongated rachilla internode (to
0.5 cm long) along with the glume(s) and intact lowest
floret.
Acknowledgements
We are grateful to Drs Soejatmi Dransfield and Wong
Khoon Meng for their valuable suggestions and
constructive comments on this paper. We also thank
the two anonymous reviewers for their comments on
the manuscript and their suggestions for improvement. This work was supported by the TRF/BIOTEC
Special Program for Biodiversity Research and Training grant T_147003, a Trinity College Dublin, Ireland
Postgraduate Studentship, and the Trinity College
Dublin Postgraduate Travel Reimbursement Fund.
References
Soderstrom, T. R. & Ellis, R. P. (1987). The position of
bamboo genera and allies in a system of grass
classification. In: T. R. Soderstrom, K. W. Hilu, C. S.
Campbell & M. E. Barkworth (eds.), Grass systematics
and evolution, pp. 225 – 238. Smithsonian Institution,
Washington, D.C.
Sungkaew, S., Stapleton, C. M. A., Salamin, N. &
Hodkinson, T. R. (in press). Non-monophyly of the
woody bamboos (Bambuseae, Poaceae): a multi-gene
region phylogenetic analysis of Bambusoideae s.s.
J. Pl. Res.
Xia, N. H. & Stapleton, C. M. A. (2006). Bonia Balansa.
In: Z-Y. Wu & P. H. Raven (eds.), Flora of China 22:
49 – 50. Science Press, Beijing & Missouri Botanical
Garden, St. Louis.
____, Chia, L. C., Li, D. Z. & Stapleton, C. M. A. (2006).
Bambusa Schreber. In: Z-Y. Wu & P. H. Raven (eds.),
Flora of China 22: 9 – 38. Science Press, Beijing &
Missouri Botanical Garden, St. Louis.
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2008