Eutrema tianshanense (Brassicaceae), a new species from Tian Shan Mountains of central Asia
Author
Hao, Guoqian
MOE Key Laboratory for Bio-Resources and Eco-Environment, College of Life Science and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610065, P. R. China & Biodiversity Institute of Mount Emei, Mount Emei Scenic Area Management Committee, Leshan 614000, P. R. China
Author
Al-Shehbaz, Ihsan A.
Missouri Botanical Garden, P. O. Box 299, St. Louis, MO 63166 - 0299, U. S. A.
Author
Liang, Qianlong
MOE Key Laboratory for Bio-Resources and Eco-Environment, College of Life Science and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610065, P. R. China
Author
Wang, Qian
Research Center for Medicine and Biology, Zunyi Medical Uniersity, Zunyi 563000, P. R. China
Author
Liu, Jianquan
MOE Key Laboratory for Bio-Resources and Eco-Environment, College of Life Science and State Key Laboratory of Biotherapy, Sichuan University, Chengdu 610065, P. R. China
text
Phytotaxa
2016
2016-11-25
286
1
23
31
http://dx.doi.org/10.11646/phytotaxa.286.1.3
journal article
10.11646/phytotaxa.286.1.3
1179-3163
13648203
Eutrema tianshanense
G.Q. Hao, J.Quan. Liu & Al-Shehbaz
,
sp. nov.
Type:—
China
.
Xinjiang
: border of Nileke Xian and Wusu Shi, near glaciers, roadsides of mountain pass,
3200–3800 m
,
28 June 2013
,
Liu,
J
.
Q
. & Hao,
G
.
Q
. 13062
(
Holotype
:
SZ
).
Fig. 4
.
Herbs, perennial, glabrous throughout, with simple or few-branced caudex and fleshy roots.
Stem
(5–)8–14(–16) cm tall, erect, simple, one to several from caudex.
Basal leaves
rosulate, somewhat fleshy; petiole (0.5–)1–1.5(–2) cm; leaf blade broadly ovate to orbicular, 0.8–1.2 ×
0.4–0.5 cm
, base rounded or truncate, margin entire, apex rounded or obtuse; middle cauline leaves linear, narrowly elliptic, or oblanceolate, 1–1.3(–2) ×
0.3–0.5 cm
, pinnately veined, sessile, base cuneate, margin entire, apex obtuse.
Racemes
ebracteate, elongated considerably in fruit, several but <20-flowered; fruiting pedicels divaricate to ascending, curved upward or sometimes straight,
3–8 cm
.
Sepals
ovate to oblong,
1.5–2 mm
, deciduous, deep red or rose; petals white, spatulate, 2–3 ×
0.7–1 mm
; filaments white, ca.
2 mm
; anthers oblong, ca.
0.2 mm
.
Fruit
linear, lanceolate, to narrowly oblong, 5–8 ×
1–2 mm
, not torulose; valves cuneate at both ends; gynophore
0.1–0.4 mm
; septum complete or rarely perforate; style ca.
0.4 mm
. Seeds not seen. Flowering: May–July; fruiting: July–September.
Additional specimens examined:
China
.
Xinjiang
: Wulumuqi Xian, Urumqi Glacier No. 1,
H
.
W
. Jintian &
Y
. Yang 106
(
PE
).
FIGURE 4.
Different stages of
Eutrema tianshanense
: a. flowering stage b. young fruit stage c. mature fruit stage.
Eutrema tianshanense
is most morphologically similar to
E. edwardsii
, and both have elongated racemes with divaricate-ascending fruiting pedicels curved upward. However, it differs from the latter by having broadly ovate to orbicular (vs. ovate to oblong) basal leaves rounded to obtuse (vs. subacute) at apex. More morphological studies at the population level are needed to establish whether or not there are other character that separate these two closely similar species. It is also morphologically similar to
E. racemosum
and
E. heterophyllum
,
but differs from the former by having ascending (vs. somewhat reflexed) fruiting pedicels and from
E. heterophyllum
by having lax and elongated (vs. compact) fruiting racemes.
One specimen
, Wu
et al.
4892 (
HNWP
,
KUN
) from Khungerab Pass, Tashkurgan Xian, was found to be morphologically similar to
Eutrema tianshanense
, but further molecular studies are needed to check whether or not it is genetically closely-related to the Tian Shan plants.