Clausena agasthyamalayana sp. nov. (Rutaceae) from Kerala, India
E. S. Santhosh Kumar, S. M. Shareef, P. E. Roy and J. F. Veldkamp
E. S. Santhosh Kumar (email@example.com), S. M. Shareef and P. E. Roy, Jawaharlal Nehru Tropical Botanic Garden and Research
Institute, Palode, iruvananthapuram district, IN-695 562 Kerala, India. – J. F. Veldkamp, National Herbarium of the Netherlands, PO Box
9514, NL-2300 Leiden, the Netherlands.
A new species of Clausena, C. agasthyamalayana is described and illustrated from the southern Western Ghats, Kerala,
India. It is similar to C. indica but diﬀers from it being of dwarf habit, and having greenish–black bark, smaller and fewer
leaﬂets, obovate and coriaceous leaves with obtuse or emarginated apex, elliptic and obtuse petals, oblong-cordate anthers,
consistently 4-locular ovary with 2 ovules in each chamber and ellipsoid fruits.
e genus Clausena Burm. f. (Rutaceae) comprises about
23 species, and is mainly distributed in the Old World
tropics from tropical Africa eastwards to Australia through
tropical and subtropical Asia and Malesia (Mabberley 2008).
In India, it is represented by 7 species (Nair and Nayar 1997),
of which 3 are recorded for Kerala (Nair et al. 2006).
During plant exploration trips in the Agasthyamala
Biosphere Reserve of the iruvananthapuram district in
Kerala, the Indian authors collected specimens of Clausena.
After critical studies they were found to diﬀer from the
known species of the genus (Molino 1994, Stone and Nair
1994, Nair and Nayar 1997). It is described and illustrated
as a new species here.
Clausena agasthyamalayana E. S. S. Kumar, Shareef,
Roy & Veldkamp sp. nov. (Fig. 1–2)
Clausenae indicae similis, habitu nano (suﬀutex ad 1.5 m altus),
foliis minoribus (1.2–5.0 contra 10–30 cm longis), foliolorum
numero minore (4–7 contra 7–13), petalis ellipticis obtusis (con-
tra oblongis acutis), antheris oblonge cordatis (contra globosis ad
ovoideis), ovario 4-loculari (contra 2–5-loculari), loculis ovulis
2 collateralibus, fructibus ellipsoideis (contra globosis) diﬀert.
Type: India. Kerala: iruvananthapuram district, Pongalap-
para, 1440 m a.s.l., 11 Jan 2011, S. M. Shareef and P. E.
Roy 70607 (holotype: TBGT!, isotypes: MH!, TBGT!).
Previously referred to as: Clausena austroindica auct. non
Stone & Narayanan: Gopanraj et al. (2004). Voucher: ca
1500 m a.s.l., Gopanraj 51815 (TBGT!).
e speciﬁc epithet refers to the type locality, Agasthyamala
Shrubs, to 1.5 m high; bark greenish–black; branchlets
cylindric, minutely puberulent, lenticellate. Leaves 8–12 cm
long; petiole 2–3 cm long, its rachis puberulent; leaﬂets
4–7, sub-opposite to alternate, 1.2–5.0 0.8–2.5 cm, coria-
ceous; lateral leaﬂets slightly asymmetric, obovate, (rarely
slightly falcate), cuneate at base, obtuse or emarginate at
apex, their margins undulate or crenate and revolute,
with glands beneath generally convex; secondary nerves
in 5–7 pairs, tertiaries faintly reticulate. Inﬂorescence
terminal, panicles 4–7 cm long; bracteoles 2, lanceolate,
unequal, ca 1 mm long, ciliate. Flowers subglobose in
bud, ca 3 mm long, 8–10 mm across when opened; pedi-
cels ca 2.5 mm long, glabrous. Calyx deeply 5-lobed with
lobes ca 1 mm long, glabrous, acute at apex, with a termi-
nal pellucid gland, minutely ciliolate along margin. Petals
5, imbricate, elliptic, 5–6 2.5–3.0 mm, white, obtuse at
apex, 3-nerved, their glands inconspicuous. Stamens 10,
5 longer and 5 shorter, 2.8 mm and 2 mm long, respectively;
ﬁlaments slightly thickened in the middle, their upper part
subulate, and lower part dilated; anthers oblong, cordate,
ca 1.5 mm long with a terminal gland on the connective.
Gynophore very short but distinct, 0.1–0.3 mm long. Ovary
subglobose, ca 2.0 2.5 mm, distinctly papillate, glabrous,
4-locular, each with 2 collateral ovules; style short, cylindri-
cal, shorter than ovary, glabrous, tipped by a truncate stigma
manifestly wider than the style. Berries ellipsoid, ca 1.5
1.1 cm, glandular, yellowish when ripe, 1-seeded. Seed
ellipsoid, glabrous, smooth.
Phenology, distribution and habitat
Clausena agasthyamalayana was seen mainly in the exposed
montane forests among rocks. e presently known popu-
lations comprise about 40 mature individuals at between
© 2014 e Authors. Nordic Journal of Botany © 2014 Nordic Society Oikos
Subject Editor and Editor-in-Chief: Torbjörn Tyler. Accepted 25 October 2013
Nordic Journal of Botany 33: 151–154, 2015
doi: 10.1111/njb.00404, ISSN 1756-1051
Figure 1. Clausena agasthyamalayana sp. nov. (a) fruiting twig, (b) leaﬂet base and apex, (c) ﬂower, (d)–(e) sepals, (f) petal, (g)–(h) anthers,
(i) gynoecium, (j) cross section of the ovary, (k) fruit, (l) seed. All drawn from Shareef and Roy 70607 by S. Suresh Kumar, JNTBGRI.
Figure 2. Clausena agasthyamalayana sp. nov. (a) ﬂowering twig, (b) close-up of ﬂower, (c) fruiting branch showing ellipsoidal fruits. All
photographs taken from its natural habitat by S. M. Shareef.
1200 and 1500 m elevation. e main associated species are:
Eugenia mabaeoides Wight, Eugenia seithurensis Gopalan &
S. R. Srinivas., Eugenia discifera Gamble, Biophytum interme-
dium Wight and Euphorbia santapaui A. N. Henry.
Clausena agasthyamalayana is similar to C. indica (Dalz.)
Oliv., but diﬀers from it by its dwarf habit, greenish–black
bark, smaller and fewer, obovate and coriaceous leaﬂets
with obtuse or emarginated apex, elliptic and obtuse petals,
oblong-cordate anthers, consistently 4-locular ovary with
2 ovules in each chamber and the ellipsoid fruits (Table 1).
Diep et al. (2009) classiﬁed Clausena into four groups
based on the chemical nature of their volatile components:
terpenoid-rich, phenylpropanoid-rich, a group with chemi-
cal variants and one with mixed composition. According to
this classiﬁcation C. indica belongs to the mixed composition
group where the species contain sabinene (53.1%), terpinen-
4-ol (13.1%), etc. (Anil et al. 2011). Gopanraj et al. (2004)
have studied the chemical composition of the essential oil
Table 1. Morphological comparison between Clausena agasthyamalayana sp. nov., C. indica, C. austroindica and C. heptaphylla.
Characters C. indica C. agasthyamalayana C. austroindica C. heptaphylla
Bark Dark green Greenish–black Green Green
Leaves (cm) 10–30 8–12 30–40 20–45
Leaﬂets 7–13, 3.5–7.5 2.0–3.5 cm,
elliptic to elliptic-ovate to
oblong or rarely
membranous, apex acute
4–7, 1.2–5.0 0.8–2.5 cm,
obovate, (rarely slightly
falcate), coriaceous, apex
obtuse or emarginate
5–9, 5.5–16.0 2.5–6.0 cm,
lanceolate to obovate,
9–11, 6.5–11.5 3.5–4.5
cm, ovate to oblong-
lanceolate or elliptic-
oblong, membraneous to
7–12 4–7 15–20 18–25
Flowers Globose in bud, to 2 mm
long, borne on 3 mm long
Sub-globose in bud, 3 mm
long, borne on 2.5 mm
Sub-globose in bud, 6 mm
long, borne on 2–5 mm long
Sub-globose, 5 mm long,
borne on 3 mm long
Petal Oblong, acute at apex,
3.5 1.2 mm, glandular
Elliptic, obtuse at apex,
5–6 2.5–3.0 mm,
Elliptic, obtuse at apex,
3–5 1.5–3.0 mm,
Oblong or suborbicular,
obtuse-rounded at apex,
3.0–3.5 1.0–1.5 mm,
Anther Ellipsoid, ca 1 mm long Oblongoid, ca 1.5 mm long Oblongoid-rhomboid, 1.5 mm
1 mm long
Ovary 2–5-locular, each with 1 or
Consistently 4-locular, each
with 2 ovules
4–5-locular, each with
2 collateral ovules
4-locular, each with
2 super-imposed ovules
Fruit Globose, ca 1.5 1.5 cm Ellipsoid, ca 1.5 1.1 cm Globose or oblate, ca
8 12 mm
Oblongoid or ovoid, ca
10–15 1 mm long
of what they called C. austroindica B. C. Stone & K. N.
Nair. According to them, it belongs to the phenyl propanoid-
rich group with elemicin (66.6%) and myristicin (19.13%)
as the main compounds. An examination of their voucher
specimen (Gopanraj 51815, TBGT!) collected at 1500 m
a.s.l., revealed that it belongs to C. agasthyamalayana. is
prompted us to make a detailed investigation of the essential
oils of C. austroindica, and it was found that it belongs to the
phenylpropanoid-rich group with tran-anethole (92%) as the
principal compound (unpubl.). It is interesting to note that
many members of the genus Clausena are rich in phenylpro-
panoids. However, anethole and estragole are the major con-
stituents of the essential oils for most of the other species of
the genus investigated (Gopanraj et al. 2004). Elimicin and
myristicin are polyoxegenated phenylpropanoids and these
have not been reported as major constituents for any member
of this genus previously investigated. is is additional sup-
port of the taxonomic distinctiveness of the new species.
Additional specimen examined (paratype)
India. Kerala: iruvananthapuram district, Pongalappara,
1440 m a.s.l., 11 Jan 2011, S. M. Shareef and P. E. Roy
Key to the species of Clausena occurring in India
Inﬂorescence exclusively axillary …………… 1. C. anisata
– Inﬂorescence terminal and/or axillary ……………… 2
Ovary glabrous or rarely slightly hairy ……………… 32.
– Ovary pilose or hirsute …………………………… 6
Ovary cylindric, ovoid or tetragonal, sulcate, 4-lobed 3.
– Ovary subglobose, glandular-papillate ……………… 4
Ovary 3-locular ……………………………… 4. C. indica
– Ovary 4–5-locular ………………………………… 5
Fruits ellipsoid …………………… 5. C. agasthyamalayana
– Fruits globose or oblate ……………..… C. austroindica
Leaﬂets 15–35; gynophore hourglass-shaped …………… 6.
…………………………………………… C. excavata
– Leaﬂets 5–9 or rarely 1–3-foliolate; gynophore cylindric
Evergreen trees; ovary globose, 5-angled …………… 7.
…….……………………………………… C. lansium
– Deciduous shrubs; ovary subglobose or oblong, entire
…….…………………………………… C. kanpurensis
Acknowledgements – e authors are grateful to Dr P. G. Latha,
Director, JNTBGRI, for the facilities provided and for constant
encouragements and to Mr S. Suresh Kumar, Artist, JNTBGRI for
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