Journal of Threatened
Taxa | www.threatenedtaxa.org | 26 July 2024 | 16(7): 25613–25616
ISSN 0974-7907
(Online) | ISSN 0974-7893 (Print)
https://doi.org/10.11609/jott.8311.16.7.25613-25616
#8311 | Received 07 December 2022 | Final received 10 June 2024 | Finally
accepted 16 July 2024
Reassessment of Strobilanthes recurva (Acanthaceae), an endangered plant from Manipur, India
Rajkumari Jashmi
Devi 1 & Biseshwori Thongam 2
1,2 Plant
Systematics and Conservation Laboratory, Plant Bioresources Division, Institute
of Bioresources and Sustainable Development (IBSD), Takyelpat, Imphal West, Manipur 795001, India.
1 rajkumjas@gmail.com, 2 b_thongam07@yahoo.com
(corresponding author)
Editor: Asok Ghosh, The
University of Burdwan, West Bengal, India. Date of publication: 26 July 2024
(online & print)
Citation: Devi,
R.J. & B. Thongam (2024). Reassessment
of Strobilanthes recurva
(Acanthaceae), an endangered plant from Manipur,
India. Journal of Threatened Taxa 16(7): 25613–25616. https://doi.org/10.11609/jott.8311.16.7.25613-25616
Copyright: © Devi & Thongam 2024. Creative Commons Attribution 4.0
International License. JoTT allows unrestricted use, reproduction, and
distribution of this article in any medium by providing adequate credit to the
author(s) and the source of publication.
Funding: M K Bhan Young Researcher
Fellowship Programme (BT/HRD/MK-YRFP/50/15/2021),
Department of Biotechnology, Government of India.
Competing interests: The authors declare no competing interests.
Acknowledgements: The authors express gratitude to
professor Pulok Kumar Mukherjee, director,
Institute of Bioresources and Sustainable Development (IBSD), Imphal, India. Heartfelt gratitude to
John R.I. Wood, Department of Plant Sciences, University of Oxford, UK for all valuable suggestions and species confirmation. We extend our gratitude
to Dr. N. Odyuo, scientist e, Botanical Survey of
India, Eastern Regional Centre, Shillong, India for his kind cooperation.
We are also grateful to the local communities of Mao Songsong, Senapati, Manipur, India, and
laboratory members, Plant Systematic and Conservation Laboratory of IBSD, Imphal, India. This work is funded by the
M.K. Bhan Young Researcher Fellowship
Programme, Department of Biotechnology, Government of India.
Abstract: The presence and status of Strobilanthes recurva C.B.Clarke (Acanthaceae)
in Manipur, northeastern India is re-assessed with a brief description and
illustration. Photographs and their conservation status are also provided. The
values of Extent of Occurrence (EOO) and Area of Occupancy (AOO) calculated as
16,313.797 km2 (VU), and 20.000 km2 (EN) respectively predicted S. recurva as Vulnerable and Endangered. Therefore, we
proposed to treat this threatened species, S. recurva
as Endangered (EN) until further information becomes available.
Keywords: Biodiversity, description,
eastern himalaya, exploration, flora, northeastern
India, rare, red list, taxonomy, threatened.
The genus Strobilanthes
Blume of the family Acanthaceae consists of
around 463 species (POWO 2024). It is distributed mostly in Asia, extending to
Japan and Korea in the north, Afghanistan and Pakistan in the west, and
northern Australia in the south. It is most diverse in the Indian subcontinent,
southern China, and mainland southeastern Asia, but many species have also been
reported to occur on the islands of southeastern Asia (Wood & Scotland
2021). Most species under the genus Strobilanthes
are recorded as rare and localized in their distribution (Wood &
Scotland 2009). Species belonging to the genus Strobilanthes
of peninsular India, the Himalaya, and hills of northeastern India are recorded
to be varied and have no connection (Wood 1994). About 65 species were reported
from peninsular India, and approximately 85 species were reported from hills of
northeastern India (Wood & Scotland 2021). The Strobilanthes
of the whole Himalayan region were discussed by Wood (1994), however,
southwestern China, upper Burma, and the hills on the Indo-Burmese border were
excluded from the study. It is reported that there is no comprehensive study on
the Strobilanthes species of the hills on the
Indo-Burmese border, which include the Indian states of Meghalaya, Nagaland,
and Manipur.
Manipur is one of the states of
the northeastern region of India. It lies between 23.83’–25.68’N and
94.31’–94.78’E and falls under the Indo-Burma Biodiversity Hotspot
(https://www.cepf.net/our-work/biodiversity-hotspots/indo-burma). In the Flora
of Manipur, no species of Strobilanthes was
previously recorded (Singh et al. 2000). However, a total of six species—Strobilanthes affinis Terao
ex J.R.I.Wood & J.R.Bennett,
S. asymmetrica J.R.I.Wood
& J.R.Benn., S. auriculata
Nees, S. clarkei J.R.I.Wood, S. cusia J.R.I.Wood & J.R.Benn., and
S. torrentium Benoist—were recorded by Ningombam (2012), of which S. auriculata
is reported to have an eight-year plietesial cycle in
Manipur (Devi et al. 2021). In addition, S. frondosa
J.R.I.Wood was also reported
to be rediscovered in Manipur (Wood et al. 2003). Among the other Strobilanthes species collected in the 19th
century from Manipur, a newspaper article reported photographic evidence for
the presence of S. recurva at Sadu chiru water fall Kangpokpi
District, Manipur (https://easternmirrornagaland.com/coneflower-photographed-in-wild-after-73-years-in-manipur/).
Strobilanthes recurva,
a rare species, was also collected from Mt. Tiyi
in Wokha, Nagaland, India by N. Odyuo and D. Roy. Herbaria specimens are present at
Botanical Survey of India, Eastern Regional Center in Shillong
bearing numbers 096495 and 096496. However, these vouchers lack information on
the altitude, habitat, and geographical coordinates (latitude and longitude).
John R.I. Wood, an expert on the genus Strobilanthes,
confirmed another collection of S. recurva
from Chittagong, Bangladesh (Collector: Mr. Mohammed Uddin). No record on the
description and illustration of these new collections of S. recurva are available on public domain.
A plant specimen of S. recurva was collected by the present author(s) from Mao
Songsong, Senapati District, Manipur, India in
February 2022 and the species was authenticated by J.R.I. Wood. Plants were
growing at an altitude of 1,835 m on a shaded streamside at the hill slope of
an open forest. Although not plentifully distributed, the collection site
recorded 20–30 mature individuals. Voucher specimens were deposited in the
Institute of Bioresources and Sustainable Development (IBSD), Imphal with accession number IBSD/M-279. In this study, the
presence of Strobilanthes recurva C.B.Clarke
(Acanthaceae) in Manipur, northeastern India is
re-assessed with a brief description and illustration. Photographs and their
conservation status are also provided below.
Results and
Discussion
Strobilanthes recurva
C.B.Clarke
J. Linn. Soc., Bot. xxv. (1889:
53).
Type: INDIA, Naga Hills, Kohima,
alt 4,500 ft (1,360 m), Clarke C.B. 41379, 30.x.1885, (Holotype K000883138!).
Description: Isophyllous
to weakly anisophyllous undershrub, 0.6--–0.8 m
height. Stem quadrangular, swollen at the base of the node. Leaves petiolate,
ovate, pubescent on both sides, 7.8–9.9 × 3.0–4.5cm, margin crenate, apex
broadly acuminate, base attenuate. Inflorescence of terminal and axillary
bracteates spikes, 3.5–3.7 × 1.1–1.3 cm. Bracts imbricate, broadly ovate,
persistent, green, glandular-pilose, 1.3–1.7 × 0.7–1.1 cm. Bracteoles 2,
linear, obtuse, 7–8 mm. Calyx 5-parted, glandular hairs present, linear,
obtuse, lobes unequal in length, 0.8 ¬ 0.9cm. Corolla 5-lobed, curved,
funnel-shaped. Corolla tube short, white, 1.5–2 × 0.2 cm, gradually widened at
the mouth., purple. Stamens 4, fertile, didynamous,
longer filament 2.2 cm, shorter filaments 0.3–0.4 cm; anthers included, 0.2–0.3
cm long. Style pilose, curved, 2.1 cm. Ovary 0.9 cm, hirsute at the apex.
Capsule oblong, hairy at the apex 1.0–1.2 cm. 4-seeded; seeds lenticular,
villous, 0.2–0.3 cm (Image 1).
Specimen examined: INDIA, Manipur, Senapati, Mao Songsong, 1,835 m, 09.ii.2022, RJ Devi & B.Thongam, M-279 (IBSD) (Image 2).
Other specimens of S. recurva
recorded so far.
India: hills of Kohima, alt 4,500
ft (1,360 m), C.B.Clarke
41379, 30.x.1885 (Holotype K000883138!) (http://specimens.kew.org/herbarium/K000883138);
India: Manipur, 14.i.1882, Watt G. 5156, E00133469
(https://data.rbge.org.uk/herb/E00133469); India: Sirhoi,
alt 6,500 ft (1,970 m), 15.iv.1948, F. Kingdon-Ward
17292 (NY2652219!) (http://sweetgum.nybg.org/science/vh/specimen-details/?irn=3451210);
India: Mt. Tiyi, Wokha,
Nagaland, N. Odyuo and D. Roy, 17.iv.2016, 096495!
and 096496; Chittagong, Bangladesh (photographs by Mr
Mohammed Uddin).
Conservation Status
No earlier evaluation was made to
assess the conservation status of this species. Since its type specimen
collection was made in the year 1885, this species is presently known from only
four locations of northeastern India, viz.: Kohima & Wokha
of Nagaland State; Ukhrul & Senapati District of
Manipur State; and another one from Chittagong, Bangladesh. Records available
so far may indicate the confinement of this species in the higher altitudinal
hills of the Indo-Burma border. Geographical coordinates are not available for
the locations from where Strobilanthes species
are collected so far except for the present study. Therefore, the standard
Geospatial Conservation Assessment Tool (Bachman et al. 2011) was used for
automatic assessment of IUCN Red Listing. The extent of occurrence (EOO) and
area of occupancy (AOO) were calculated as 16,313.797 km2, and
20,000 km2, respectively.
Keys to
species of Strobilanthes recorded from
Manipur, India
1a. Inflorescence short terminal spike; Leaves
petiolate; Bracts obovate – subspathulate; Bracteoles
oblanceolate subspathulate; Corolla lobe pale sulphur or white
………...............................................................…………. S. aymmetrica
1b. Inflorescence axillary or terminal spike;
Leaves subsessile; Bracts obovate or elliptic
obovate; Bracteoles oblanceolate or subacute; Corolla lobe white or purple
…….............…….............…….........…….............…….............…….............…….. 2
2a. Inflorescence small axillary & terminal
panicle; Bracts obovate; calyx lobe equal; Corolla lobe glossy violet, curved
………. S. clarkei
2b. Inflorescence terminal or axillary spikes;
Bracts obovate to oblanceolate or leaflike imbricate; Calyx unequal; Corolla
not glossy, slightly bent to curved, lobe pale blue to purple colour ……….............…….............…….............……....….………
3
3a. Anisophyllous, subsessile; Inflorescence short, nodding subcapitate spike on simple or sparsely branched axillary
branchlets; Bracts elliptic-obovate with scattered gland dots; Corolla
straight, lobe pale blue colour …………………………………….. S. frondosa
3b. Isophyllous to
weakly anisophyllous, subsessile
or petiolate; Inflorescence terminal or axillary spike; Bracts leaflike
imbricate or obovate or oblanceolate; Corolla straight to slightly bent or
highly curved, lobe blue colour ….…......……………………………….
4
4a. Leaves oblong, ovate, elliptic, glabrous or
pilose; Cystolith absent ........………............………..………..…. 5
4b. Leaves ovate to elliptic, pubescent; Cystolith present …...........................................................……..……. 6
5a. Leaves sessile, lanceolate, oblong, cordate,
both surface pilose; Bracts imbricate broadly ovate to obovate spathulate;
Corolla funnel shape, lobe pale purple ……………............................………………………………….. S. auriculata
5b. Leaves petiolate, elliptic, ovate, glabrous
or pubescent; Bracts leaflike imbricate broadly ovate or oblanceolate to
obovate; Corolla straight to slightly bent or highly curved, lobe blue colour …………………………........……………………………..
7
6a. Leaves both surface sparsely stringose, densely covered with subulatecystoliths;
Bracts imbricate broadly obovate, rhomboidal or elliptic; Corolla purplish-blue
to violet, curved ……………..........................................……………………..… S. affinis
6b. Leaves adaxially sparsely pubescent,
numerous cystolith; Bracts obovate to subrhombic, distinctly angled; corolla blue to violet, curved
…………………………...........................................................…………………….…….
S. torrentium
7a. Isophyllous to
weakly anisophyllous; Leave glabrous; Bracts
oblanceolate to obovate; Corolla straight to slightly bent, lobe blue …… ………………….....……........................................................................................................……….…..
S. cusia
7b. Isophyllous; Leaves pubescent on
both sides; Bracts broadly ovate; Corolla curved, funnel shaped, lobe purple
…………... S. recurva.
For
images - - click here for full PDF
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