Bauhinia hekouensis (Leguminosae, Caesalpinioideae), a New Species from Yunnan, China

2013·3 MB·English

by  Tieyao Tu

New
Bauhinia
hekouensis (Leguminosae, Caesalpinioideae), a Species
from Yunnan, China
*
Zhang
Tu and Dianxiang
Tieyao
Key
Laboratory of Plant Resources Conservation and Sustainable Utilization,
South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650,
Guangdong, Republic China
People’s of
* Author correspondence: [email protected]
for
&
Abstract. Bauhinia hekouensis T. Y. Tu D. X. Clavatae consists of ca. 22 species occurring in
Zhang (Leguminosae, Caesalpinioideae), a narrow tropical southeastern Asia (de Wit, 1956; Larsen
et
endemic from Hekou County, Yunnan Province, in al., 1980; Wunderlin et al., 1987), with one species
southwestern China, described and The and one subspecies previously recorded from Yunnan
is illustrated.
new species can be diagnosed by a combination of Province of China (Chen 2010).
et al.,
&
Tu
Bauhinia hekouensis Y. D. X. Zhang,
T. sp.
with nine to 11 nerves; terminal, racemose inflores-
nov. TYPE: China. Yunnan: Hekou Co., Nanxi
cences; spindle-shaped, slightly falcate flower buds
Town, Baishahe, 22°41.237'N, 103°57.597'E,
with acute apices; tubular hypanthium; five freely
169 m, near stream, 11 Oct. 2008, Tu 511
T.
reflexed sepals during anthesis; and large white
(holotype, IBSC; isotypes, IBSC, KUN). Figure
The 1.
flowers with oblanceolate, crisped petal blades.
new
lorphology suggests an of the
affinity
Wunderlin Haec Bauhmia DC.
series Clavatae (de Wit) of species a coccinea (Lour.) et B.
)
nervosa (Wall, ex Benth.) Baker petiolo 2.5-6 (nee 1.5-3)
Phanera Wunderlin Bauhinia
section (Lour.) in L.,
DC. and
especially to the species B. coccinea (Lour.)
B. nervosa (Wall, ex Benth.) Baker.
Key
words: Bauhinia, Caesalpinioideae, China,
IUCN Red
List, Leguminosae. Large liana, extending into upper canopies of host
The legume genus Bauhinia L. comprises ca. 300 pubescent, singly inserted at nodes; branchlets terete,
species of trees, shrubs, and lianas. As the largest pubescent when young, gradually glabrescent. Leaves
X
genus of the tribe Cercideae (Leguminosae, Caesal- ovate to suborbicular, up to 12 14 cm; the blades
pinioideae), occurs throughout pantropic areas, bifid to 1/3 divided with a broad
it
s
Asia and South America, extending into southern young to glabrate, blade base cordate, with primary
North America (Wunderlin et ah, 1987). Forty-two nerves 9 to 11, sLoul. connected by transverse
species of Bauhinia from China were documented in secondary nerves; petioles green, 2.5-6 cm; stipules
X
3-6 2-A
the Flora Reipublicae Popularis Sinica (Chen, 1988), deciduous, obovate, rotund or orbicular, ca.
mm,
and several additional species have been subse- glabrous or minutely puberulent. Inflorescences
quently described or recorded (Zhang, 1993; Zhang racemose, terminal, unbranched, 5-25 cm; axis
&
Chen, 1996, 1998). There are 47 species greenish pubescent, with up to ca. 30 flowers; pedicels
recognized in the recently published Flora of China slender, 2. 1-3.4 cm, puberulent; bracts lanceolate,
X
10-15 2-3 mm; 4-8
(Chen et al., 2010). During an exploration for green, bracteoles linear, acute,
mm,
Bauhinia in southwestern China as part of our long- inserted above the middle of the pedicels. Flower
term endeavor on the systematics and evolution of the buds green, spindle-shaped, slightly falcate, apex
X
genus, an apparently new species was discovered. acute, 15-25 3-5 mm; hypanthium tubular, 17-21
X
The new species exhibits characteristics of the series 1. 5-2.5 mm; calyx green, splitting into 5 sepals on
Clavatae (de Wit) Wunderlin in Bauhinia, from the apex of the hypanthium, acicular, subulate,
section Phanera (Lour.) Wunderlin, subgenus Pha- reflexed at anthesis, 1.8-2.5 cm; petals arranged
&
nera (Lour.) Wunderlin, K. Larsen Larsen.
S. S. It
shows close affinities to B. coccinea (Lour.) DC. and white, crisped, the lower surface and edges of the
&
B. nervosa (Wall. Benth.) Baker. Bauhinia upper surface sparsely pubescent, the median zone of
ser.
May
Novon 22: 332-335. Published on 24 2013. 10.3417/2010017
doi:
Volume Number 3 Tu & Zhang 333
22,
2013 Bauhinia (Leguminosae) from Yunnan, China
3-
the upper surface densely pubescent; the posterior and then reflexing upward; anthers maroon,
elliptic,
mm,
blade of the corolla oblanceolate, the lower part of the 4 opening by longitudinal staminodes
slits; 2,
blade gradually, the upper part of the blade more orm, 1 mm; ovary densely pubescent, on a 8-15
filif
X
14-22 5-9 mm;
abruptly, narrowing the apices,
to
the blades of the lateral petals slightly narrower than
X
12-21 3-9 mm;
the posterior ones, the petal claws
±
green, equal to or slightly longer than petal blades,
and Bauhinia
pubescent; fertile stamens 3, opposite to the petals; Distribution habitat. hekouensis is
32-47 mm, known
filaments green, glabrous, starting outward currently only from the type locality in a

Tu &;