Euphorbia sahyadrica (Euphorbiaceae), a new species of succulent shrub from the wet zone of the northern Western Ghats, Maharashtra, India
Author
Malpure, Nilesh V.
0000-0003-0018-1115
Department of Botany, S. S. G. M. College, Kopargaon- 423601, District Ahmednagar, MS, India. & nmalpure @ gmail. com; https: // orcid. org / 0000 - 0003 - 0018 - 1115
nmalpure@gmail.com
Author
Raut, Prashant S.
0000-0003-3800-8553
Department of Botany, S. S. G. M. College, Kopargaon- 423601, District Ahmednagar, MS, India. & Prashant 28318 @ gmail. com; https: // orcid. org / 0000 - 0003 - 3800 - 8553
rashant28318@gmail.com
Author
Sardesai, Milind M.
0000-0002-7802-3988
Department of Botany, Savitribai Phule Pune University, Pune- 411007, MS, India. & sardesaimm @ yahoo. co. in; https: // orcid. org / 0000 - 0002 - 7802 - 3988
sardesaimm@yahoo.co.in
Author
De Jong, Bruce E.
0000-0002-2002-9308
Independent Researcher, AHM Trust, B. Dharmathupatti- 625582, Theni Dt., TN, India. & tbdejong 2000 @ yahoo. com; https: // orcid. org / 0000 - 0002 - 2002 - 9308
tbdejong2000@yahoo.com
text
Phytotaxa
2021
2021-05-17
500
4
285
293
https://www.mendeley.com/catalogue/8133ed31-d263-34d3-8465-50f024e7ff01/
journal article
10.11646/phytotaxa.500.4.4
1179-3163
5424678
Euphorbia sahyadrica
Sardesai & Malpure
,
sp. nov.
(
Figs.1–3
)
Diagnosis:—
Lactiferous, armed succulent allied to
E. nivulia
but differing in its spreading shrub-like habit, light grey bark with closelypacked horizontal branch scars and fissures, fleshy elliptical leaves with obtuse apices, short petioles, and easily visible lateral nerves, protruding tubercles in a spiral pattern, spine shields bearing two pairs of spines, cymes with short peduncles that usually have a bisexual cyathium in the central position, and capsules with cocci that are tapering laterally and do not have a prominent suture between lobes.
T
ype
:—
INDIA
.
Maharashtra
:
Raigad district
.,
Harihareshwar
,
18°01.052’N
,
73°01.415’E
, elev.
53 m
,
16 February 2019
,
N
.
V
.
Malpure
0030
(
holotype
CAL!; isotypes BSI!, SUK!).
Spreading, profusely branched shrub up to 4(−5) m tall, wider than tall with persisting lower branches.
Stem
woody, rough, with somewhat compressed spiral rows of spines.
Bark
silvery grey with persistent scars of tubercles and branches, and with closely packed horizontal fissures.
Branches
terete,
3–5 cm
diam., whorled or not, often nearly horizontal.
Tubercles
protruding up to
1 cm
, arranged in a spiral pattern.
Spine shields
circular, pale brown when young then becoming ashy grey, each with 2 pairs of spines, the upper pair
1 mm
long, sometimes caducous, the lower pair dominant and usually persistent, divergent,
2–5 mm
long.
Leaves
12−18 ×
5−8 cm
, subsessile with petiole
0.5–1 cm
long, attenuate at base, usually elliptic or obovate, apex obtuse and mucronulate, fleshy, slightly hyaline, margin entire with prominent midvein and visible lateral nerves, falling in dry season, leaving a large light-coloured leaf scar.
Cymes
1(−2) per flowering eye, terminal or subterminal, in dichasium, often branching up to two levels, the central cyathium sessile, most often bisexual, lateral cyathia on peduncles, bisexual.
Peduncles
0.8−1.2 cm
long,
3–4 mm
thick, smooth, glabrous, green.
Bracts
opposite, 2.5–3 ×
1.4–2.5 mm
, ovate to obtuse, minutely fimbriate, yellowish, sub-keeled.
Involucre
broadly cupular, 7–10 ×
3–4 mm
.
Glands
5, transversely oblong,
6–7 mm
, with a wavy border, convex, yellowish green. Involucral lobes 5, 1.2–1.5 ×
1.3–1.6 mm
, broadly ovate, fimbriate, quincuncial in bud stage.
Male florets
in 5 fascicles, 6−7 per fascicle, 1.8–5.0 mm long, subtended by laciniate bracteoles, pedicellate; pedicel 2.0−
3.5 mm
long, colourless, shiny, persistent and protruding; filament 1.0−
1.5 mm
long, yellow; anther 0.6−0.7 × 0.8−1.0 mm, dull orange to yellow, basifixed, orbicular, longitudinally dehiscent.
Female florets
: gynophore
2 mm
when unfertilised, becoming
1.2−1.5 cm
long, recurved when immature, green, perianth lobes 3; ovary trigonous; styles 3, connate up to middle; stigma bifid, papillose.
Capsules
exserted, trilobed
1.1−1.3 cm
diam, smooth, glabrous, green with stippled reddish margins converging on septa, cocci tapering laterally without prominent suture between cocci.
Seeds
globose c. 5 ×
4 mm
, blackish grey, mottled with tan spots converging around the medium raphe.
Chromosome number
:—2n = approx. 240.
Phenology:—
Flowering January–April and fruiting February–May.
Distribution and habitat:—
Currently
E. sahyadrica
is only known in the coastal hills of Raigad District of
Maharashtra
near Harihareshwar and Alibag. These sites are separated by approximately
100 km
(Map 1). The new species grows in shallow soil on the rocky basaltic hills facing the sea. Our survey found more than 150 fully grown individuals within this scrub vegetation habitat. Other species growing in association with
Euphorbia sahyadrica
were
Bombax ceiba
L.,
Carissa carandas
L.,
Cordia myxa
L.,
Grewia asiatica
L.,
Helicteres isora
L.,
Lantana camara
L.,
Leea indica
(Burm.f.) Merr.,
Santalum album
L., and
Lannea coromandelica
(Houtt.) Merr.
MAP 1.
Distribution of
Euphorbia sahyadrica
Sardesai & Malpure
(green squares) and
Euphorbia nivulia
Buch.
-Ham.(blue dots).
Additional specimen examined (
paratype
)
:—
INDIA
.
Maharashtra
:
Raigad district
, on the way to
Varasoli
, 18°65.849’N, 72°87.737’E,
15 March 2019
,
N
.
V
.
Malpure
109
(MH!).
Additional specimens of
E. nivulia
examined:—
INDIA
.
Andhra Pradesh
:
East Godavari Dt.
,
Ontimamidi Vagu Thed Palandi
,
Jamladugu
,
27 March 1988
,
N
.
Rama Rao
&
T
.
Ravishankar
86546
(
MH
!).
Kadappa Dt.
,
Palkonda Hills
,
1500 ft
,
July 1884
,
J
.
S
.
Gamble
14028
(
CAL
!).
Vishakhapatnam Dt.
,
Kilagada
,
9 March 1965
,
G
.
V
.
Subbarao
22577
(
MH
!);
Jalaput
,
7 January 1969
,
G
.
V
.
Subbarao
33306
(
MH
!);
Simhachalam Hill
eastern slope,
6 May 1964
,
G
.
V
.
Subbarao
19379
(
MH
!)
.
Chhattisgarh
:
Bijapur Dt.
,
Kandla Patri-Indravati Tiger Reserve forest
,
20 May 1987
,
A
.
Kumar
16278
(
CAL
!)
.
Karnataka
:
Bagalkot Dt.
,
Badami
,
8 March 1909
,
S
.
V
.
Shevare
s.n.
(
BSI
!).
Hassan Dt.
,
Nagpuri Forest
,
Arasikere
,
1 April 2015
,
R
.
K
.
Swamy
&
A
.
Singh
0694
(
JCB
!).
Mandya Dt.
,
Shivasamudram
, in dry deciduous forest,
3 March 1978
,
S
.
M
.
Ahamed
KFP324
(
JCB
!).
Shivamogga Dt.
[
Mysore
],
Talguppa
,
October 1908
,
A
.
Meebold
7305
(
CAL
!)
.
Kerala
:
Trissur Dt.
,
Solayar
to
Malakkampara
ghat road,
1300m
,
5 February 1984
,
K
.
Ramamurthy
80846
(
CAL
!)
.
Madhya Pradesh
:
Damoh Dt.
,
Damoh
,
2 October 1908
,
J
.
R
.
Parno
29935
(
CAL
!).
Hoshangabad Dt.
,
Dhupgarh
,
430m
,
20 August 1949
,
V
.
Narayanabirami
3380
(
CAL
!).
Nimar Dt.
,
7 December 1907
,
D.
O
.
Witt
27835
(
CAL
!).
Sagar Dt.
,
Hirapur
,
450m
,
3 March 1960
,
K
.
Subramaniyam
10171
(
CAL
!);
Sagar Cantonment
,
19 Oct. 1906
,
A
.
Blythe
28728
(
CAL
!)
.
Odisha
:
Khorda Dt.
,
Chandaka Forest
,
24 Feb. 2016
,
A
.
Singh
,
R
.
K
.
Swamy
,
N
.
Page
&
K
.
Sankara Rao
0470
(
JCB
!).
Mayurbhanj Dt.
,
Simlipal Forest
,
Baniabasa
,
23 March 2002
,
D. D. Bahali
& D.
K
.
Agarwala
560
(
CAL
!)
.
Tamil Nadu
:
Dharmapuri Dt.
,
Hogenakkal
,
14 March 1965
,
E
.
Vajravelu
23543
(
MH
!);
Dharmapuri
to
Jhalwania
,
10 February 1987
,
M
.
Prasad
39455
(
CAL
!).
Kanyakumari Dt.
,
Poovathu Odai
,
Boothapandy Range
via
Karumparai Palrulum
,
23 February 1983
,
A
.
N
.
Henry
77127
(
CAL
!).
Nilgiri Dt.
,
Mayar River
bank,
16 February 1972
,
B
.
D. Sharma
39809
(
MH
!).
Ramnad Dt.
,
Aiyanar Kovil forest
,
12 March 1970
,
E
.
Vajravelu
33683
(
MH
!).
Salem Dt.
,
Chinnakalrayans
,
700 m
,
20 February 1979
,
T
.
S
.
Jeyaseelan
21871
(
RHT
!).
Yercaud
,
23 March 2016
,
R
.
K
.
Swamy
,
N
.
Page
,
A
.
Singh
&
K
.
S
.
Rao
361
(
JCB
!).
Tenkasi Dt.
,
Honey Falls
to
Courtallam
,
20 March 1958
,
K
.
Subramanayam
5598
(
CAL
!).
Tiruchirapalli Dt.
,
Pachaimalais
,
1000m
,
23 March 1977
,
D.
I
.
Arockiasamy
7004
(
RHT
!);
Pachaimalais
,
100m
,
29 March 1983
,
K
.
M
.
Matthew
,
S
.
J
.
Britto
, &
N
.
Rani
29409
(
RHT
!).
Telangana
:
Bhadradri Kothagudem Dt.
[
Godavari
],
Dummagudem
500ft.
,
February 1885
,
J
.
S
.
Gamble
15196
(
CAL
!)
.
West Bengal
:
Burdwan Dt.
, n.d.,
A
.
J
.
Dutt
1163
(
CAL
!)
.
FIGURE 1.
Comparison of
Euphorbia sahyadrica
Sardesai & Malpure
and
Euphorbia nivulia
Buch.
-Ham. (A–C)
Euphorbia sahyadrica
Sardesai & Malpure.
(A) Habit, (B) Leaves, (C) Spine shield. (D–F)
Euphorbia nivulia
Buch.
-Ham. (D) Habit, (E) Leaves, (F) Spine shield. Photos A–C by Milind Sardesai, D–F by Nilesh Malpure
FIGURE 2.
(A–E)
Euphorbia sahyadrica
Sardesai & Malpure.
(A) Flowering branch, (B) Capsules, (C) Involucral lobe, (D) Bract, (E) Seed; (F–J)
Euphorbia nivulia
Buch.
-Ham. (F) Flowering branch, (G
)
Capsules, (H) Involucral lobe, (I) Bract, (J) Seed. Photos: A–J by Nilesh Malpure.
FIGURE 3.
Illustration of
Euphorbia sahyadrica
Sardesai & Malpure.
(A) Habit, (B) Stem and spine shields, (C) Leaf, (D) Cyme, (E) Bract, (F) Bisexual cyathium, lateral view, (G) Bisexual cyathium, top view, (H) Staminate flowers, (I) Involucral Lobe, (J) Capsule, lateral view, (K) Capsule, top view, (L) Seeds, top and lateral view. Illustrated by B. De Jong from
N.V.
Malpure
0030.
SRI LANKA
.
Anuradhapura Dt
:
Padaviya
,
Wahalkada Saddle Dam
, rocky dry zone forest,
17 August 2014
,
S
.
P
.
Ekanayaka
Y14
(
PDA
!)
.
Conservation status:—
A detailed study of the distribution and range of
E. sahyadrica
has not been conducted. The IUCN redlist category would be DD (Data Deficient) (
IUCN Standards and Petitions Committee, 2019
). These plants are somewhat threatened by the presence of nearby touristic activity at Harihareshwar beach and by the presence of grazing animals which endanger seedlings. Though the extant populations appear healthy, our impression is that these plants could later be found to be Vulnerable or even Endangered.
Etymology:—
The specific epithet ‘
sahyadrica
’ refers to the northern Western Ghats which are popularly known as the Sahyadris.
Discussion:—
Mehra & Choda (1978)
carried out cyto-taxonomical studies in the genus
Euphorbia
and proposed
x
= 10 as the primary base number. Considering that a wide range of polyploid taxa from 2
n
= 12 to 2
n
= ca. 200 occur within the genus,
Hans (1973)
proposed
x
= 7 and
x
= 10 as the primary base numbers for the genus
Euphorbia
. Our cytological studies found that
E. sahyadrica
has approximately 2
n
= 240 chromosomes. The level of ploidy is
24x
taking the base number as
x
= 10. It was noted that
E. nivulia
samples from both the above locations have only 2
n
= 60 chromosomes (
Fig. 4
). This confirms the work of
Mehra & Choda (1978)
who reported
n
= 30 as the chromosome number for
E. nivulia
.
A side by side comparison of
E. nivulia
and
E. sahyadrica
shows a number of distinguishing characteristics that separate the two species (
Table 1
).