A new species of billolivia (gesneriaceae) from central vietnam

Phytotaxa 291 (1): 089–093
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ISSN 1179-3155 (print edition)

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PHYTOTAXA

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A new species of Billolivia (Gesneriaceae) from Central Vietnam
NGỌC-SÂM LÝ
Department of Biological Resources, Institute of Tropical Biology, Vietnam Academy of Science and Technology, 85 Trần Quốc Toản
road, District 3, Hochiminh City, Vietnam. E-mail: and

Abstract
Billolivia middletonii, a new species from Cà Ðam Mountains, Quảng Ngãi Province, Central Vietnam, is described and illustrated. A morphological description, a colour plate, the distribution, ecological information, the conservation status, and
notes to species of Billlolivia in Vietnam are given.

Introduction
The genus Billolivia Middleton et al. (2014a: 255) was recently described by Middleton et al. (2014a). It comprises at
least eight species of small perennial caulescent herbs growing mostly on sandstone substrates in lowland to montane
evergreen closed forest in Southern Vietnam (Middleton et al. 2014a, 2014b, Luu et al. 2015, Vũ et al. 2015). During
botanical investigations in Central Vietnam in 2016, a new lithophytic species of Billolivia was discovered and collected
from Cà Ðam Mountains, Tây Trà district, Quảng Ngãi Province, Vietnam. The plant is a small caulescent herb with
a long pubescent petiole, obovate to elliptic leaves, a 5-lobed calyx almost divided to base, and a flower-shape which
is very similar to other species in the genus (see Middleton et al. 2014a, Luu et al. 2015, Vũ et al. 2015). After careful
examination of the material from E, P, SING, VNM, VNMN, SING herbaria and comparision to Billolivia species in
southern Vietnam, it was confirmed that the plant is new to science and is here described as Billolivia middletonii. All

measurements and characters in the description were made from mature, living plants and herbarium specimens. The
terminology in general follows Beentje (2010) and Middleton et al. (2014a, 2014b). The IUCN assessment uses the
criteria given in IUCN version 3.1 (2012).

Taxonomic treatment
Billolivia middletonii N.S. Lý, sp. nov.
Similar to B. kyi in the long pubescent petioles, the shape of the lamina, and the 5-lobed ovate calyx almost divided to base, but differing
in the glabrous stems (vs. densely pubescent), the lamina being glabrous adaxially (vs. sparsely pubescent adaxially), much longer
bracts, 25–52 mm long (vs. shorter, up to 15 mm long), the oblong-obovate corolla lobes with violet lines (vs. orbicular, dark to redpurple), the white corolla throats having two yellow patches at base of lower lip, with violet lines (vs. dark red with a yellow patch),
the longer and pale greenish filaments, 8–10 mm long (vs. white with long red patch, 5–6 mm long), fruit 20–25 mm long, ovoid to
oblong-ovoid (vs. 14–16 mm long, ellipsoid).
TYPE:—VIETNAM. Quảng Ngãi Province, Tây Trà District, Trà Trung Commune, Cà Ðam Mountains, Bà Noong stream, 1009 elev., 25
September 2016, Lý Ngọc Sâm, Lý-817 (holotype VNM!, isotypes P!, VNM!). Fig.1 & 2.

Lithophytic, caulescent, perennial herbs with short decumbent stems, robust, to 30 cm long, 1.8–2.2 cm in diam.,
light brown, with numerous strongly prominent leaf scars, glabrous, except for sparse hairs to 2 mm long at apex in
young plants (Fig.1A, C). Leaves alternate, crowded near stem apex, internodes 0.8–1.8 cm long, with roots at the
nodes near base; petioles fleshy, 9.2–18.5 cm long, 0.5–0.7 cm in diam. at the middle, pale greenish, densely covered
in a mixture of long brown hairs to 4.5 mm long and shorter appressed brown hairs toward apex, hairs sparse at base;
Accepted by Jesús González-Gallegos: 9 Dec. 2016; published: 6 Jan. 2017

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lamina thick, coriaceous, slightly unequal, elliptic-obovate to broadly elliptic, 12.5–21.5 × 9–14.5 cm, base obtuse
to somewhat truncate, attenuate when young, apex short acute to slightly obtuse, margin coarsely crenate, slightly
deflexed, secondary venation 10–13 veins on each side of midrib, sunken above, strongly prominent below, with
weaker intersecondaries veins between, tertiary venation alternate percurrent, adaxial lamina dark green, glabrous,
margin ciliate with brown hairs to 2.5 mm long, abaxial lamina glaucous greenish, with sparsely brown hairs to 3 mm
long between the veins and densely so with both short and long brown hairs to 3.5 mm long on midrib and venation

(Fig. 1D). Inflorescences axillary, single or distichously compound-cymes, peduncle pale brown-red to tinged greenish,
densely short brown pubescent to 1.5 mm long; simple cymes with a peduncle 6.5–13 mm long and 2–3 mm in diam.,
6–8-flowered, compound cymes with peduncle 7–13.5 mm long, 3–3.5 mm in diam. and second axes 2–6 mm long,
2–3 mm wide in diam., sometimes sessile, 4–8-flowered in each cyme; bracts narrowly ovate, with a longitudinally
prominent vein on the outside, outside pale brown-red [pinkish], tinged pinkish-green towards apex, with sparsely
short brown pubescence to 1.5 mm long, denser in the middle, inside whitish or greenish, glabrous, apex acute, ciliate,
margin ciliate with brown hairs to 2 mm long (Fig. 1I–J); basal bracts (25–)32–52 × 7–9 mm, second bracts [of the
subtending second cyme] 24–39 × 5–7 mm; pedicels 18–24 mm long, 1.8–2.5 mm diam. in the middle, pale brownred [pinkish] or greenish, densely brown pubescent to 2.5 mm long. Calyx of 5 ± equal lobes, almost divided to base
with connate part < 1 mm long, 21–26 mm long, 3–4 mm wide at widest point, apex acute, margin ciliate, with a
longitudinally prominent vein on the outside, pale brown-red [pinkish] to greenish outside with sparse brownish hairs
of 2 mm long, paler and glabrous inside (Fig. 1L). Corolla 21–25 mm long, composed of a narrow tube which slightly
curves downwards in lower ⅓ and slightly flares towards mouth, and a 2-lipped limb, tube and lobes white outside,
with dark violet lines from the upper half of the inside of the tube and onto lobes, ventral surface of throat and upper
half of tube with 2 yellow stripes in line with lobe sinuses, upper halves of lobes white (Fig. 1K1–K3, M); tube 16–19
mm long, 10–11 mm wide at throat; upper lip 2-lobed, ca. 10–12 mm long, sinus between lobes ca. 5 mm, lobes 7–11
× 5.5–8 mm; lower lip 3-lobed, c.16–18 mm long, lobes somewhat oblong-obovate, apices rounded, lateral lobes ca.
8–12 × 6.5–9 mm, medial lobe 9.5–14 × 6–8 mm; corolla outside glabrous in basal half of tube, with sparse short
white hairs in upper half, with short and long hairs on upper part of tube and outside of lobes, tube inside glabrous and
with short glandular hairs on inside basal 2/3 of lobes. Stamens inserted at ca. 10 mm from corolla base (Fig. 1M–N);
filaments ca. 8–10 mm long, narrow at base, widening around middle and slightly curved, white at base, pale greenish
towards apex, with dense glandular hairs in upper half; 2 fertile anthers ca. 2–3 × 2–3 mm, thecae ± parallel, 2 anthers
fused by tips; lateral staminodes minute, ca. 1.5 mm long, white, glabrous; medial staminode minute, ± 1 mm long,
white, glabrous. Disc bowl-shaped, shallowly 5-lobed, ca. 1–1.5 mm high, 2.5–3 mm in diam., white, glabrous. Ovary
ca. 5.5–6 mm long, 2–3 mm wide at base, white glandular pubescent at apex (Fig. 1O); style 6–8 mm long, white,
densely white glandular pubescent throughout with hairs up to 1 mm long; stigma 2-lobed, 1–2 mm long, 1.5–2 mm
wide, lobes ca. 1 mm long, glabrous. Fruits narrowly ovoid to oblong-ovoid, 20–25 × 5–6.5 mm, translucent greygreenish, with sparse hairs at apex (Fig. 1G). Seeds many, ovoid, 0.2–0.3 × 0.2 mm, black.
Distribution and Ecology:—Currently known only from the type locality in the Cà Đam Mountains, where two
subpopulations of mature, flowering and fruiting plants of Billolivia middletonii were found. It grows in rocky stream
beds in lower primary sub-montane evergreen broadleaf forest at about 1000 elev. It is locally abundant.
Phenology:—Billolivia middletonii was observed with mature fruits in late July and in flower and with young

fruits in late September in its natural habitat. This would suggest it flowers several times per year with flowering from
May to September, and fruiting from July to December.
Conservation status:—Critically Endengered (CR B2a,b(ii,iii)). Billolivia middletonii occurs in a single locality
on Cà Ðam Mountains with fewer than 100 individuals and with a total Area of Occupancy of less than < 0.5 km2.
Although this species is under the protection of the local authorities of the Department of Forest Protections in Tây
Trà and Trà Bồng Districts, Quảng Ngãi Province, the populations are, however, vulnerable and continuing to decline
in area, extent and quality of habitat due to destruction through human activities, such as harvesting of timber and
non-forest products, especially clearing of forest land for Acacia plantations. According to the IUCN Red list criteria
(IUCN, 2012), this qualifies it as Critically Endengered (CR B2ab(ii,iii)) which is therefore proposed here.
Additional specimens examined (Paratypes):—VIETNAM. Quảng Ngãi Province, Tây Trà District, Trà Trung
Commune, Cà Ðam Mountains, Bà Noong stream, 1009 m elev., September 2016, Lý Ngọc Sâm, Lý-816 (VNM!); the
same locality, 29 July 2016, Lý Ngọc Sâm, Lý-784 (VNM!); the same locality, 1008 m elev., 25 September 2016, Lý
Ngọc Sâm, Lý-815 (VNM!).
Etymology:—The specific epithet of the new species is named in honour of Dr David J. Middleton of the Singapore
Botanic Gardens for his continuing contribution to our understanding of the Gesneriaceae in Asia, including as the first
author on the paper in which the genus Billolivia was first described.
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FIGURE 1. Billolivia middletonii. A. Habit. B. Lower part of the stem showing axillary inflorescence. C. Detail of basal stem showing
large leaf scars and infructescence. D. Detail of plant with infructescence, and close-up of abaxial leaf margin and petiole. E. Front view of
flower. F. Side view of flower on its single cyme. G. Longitudinal and cross-section of fruit. H. Detail of a compound cyme (back view).
I. Basal bracts. J. Upper bracts. K1–K3. Detail of flowers (from left): side, below and top views. L. Outer and inner views of the 5-lobed
calyx. M. Longitudinal section of the flower. N. Front and side views of stamens. O. Side and front views of pistils. All photographs from
the type, Lý-817.

A NEW SPECIES OF BILLOLIVIA FROM VIETNAM

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FIGURE 2. Distribution map of Billolivia middletonii in Central Vietnam.

Notes:—The calyx in Billolivia is more or less divided to the base in some species and fused into a tube in others.
The species with the calyx divided to base are B. kyi Luu & Tran in Luu et al. (2015: 362), B. minutiflora Middleton et
al. (2014a: 258), B. poilanei Middleton et al. (2014a: 260), B. vietnamensis Middleton et al. (2014a: 261), and the new
species (Figure 1L). Of these, B. kyi and B. middletonii differ substantially from the other three species in having much
longer petioles to ≥ 9 cm long. Billolivia middletonii differs from B. kyi in the morphological features noted above.
Billolivia middletonii also resembles B. longipetiolata Middleton et al. (2014a: 256) and B. tichii Luu et al. in Vũ et
al. (2015: 190) in having long pubescent petioles, obovate to elliptic leaves, and ovate calyx lobes. Densely pubescent
stems, coarsely dentate margins, elliptic or deltoid lobes of the tubular calyx, corolla lobes being orbicular to deltoid
with violet or red to pink apexes, and glabrous ovaries distinguish these species from B. middletonii.
The currently known species of Billolivia are found in a relatively small area in the southern Annammite Mountains
on the Ðà Lạt plateau (Lâm Đồng Province) and in Bình Phước and Ninh Thuận Provinces in Vietnam (Figure 2). The
species are small terrestrial herbs and are quite locally endemic (Middleton et al. 2014a, 2014b, Luu et al. 2015, Vũ et
al. 2015). With the new species described here, nine species of Billolivia are now recorded, all of them from Vietnam.
The genus, is, however reported for the first time from Quảng Ngãi Province which extends the distribution range of
the genus from Southern to Central Vietnam and ca. 400 km further north than previously known localities for the
genus (see Figure 2). Further field work in the Annamite mountains is necessary to see if the distributional limit of
Billolivia species in Vietnam could be even further to the north.
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Acknowledgement
This study is supported by grants from the ITB Key Laboratory of Plant Cell Biotechnology (No.09/THSHNĐ/17/03/2016) and the International Collaboration Project between Vietnam Academy of Science and Technology,
Vietnam and Centre National de la Recherché Scientifique, France (VAST.HTQT.PHAP.02/N16–17). The author is

indebted to Hoàng Nghĩa Sơn, the director of the Institute of Tropical Biology (ITB), for his support in continuing my
research, to Trần Đại, the deputy head of the Department of Forest Protection (Quảng Ngãi Province) and Nguyễn Quốc
Bảo and Phạm Quang Luân (Trà Trung People’s Commune) for issuing permits for the fieldwork, to Nguyễn Trần Vỹ,
the head of the department of Biological Resources (ITB) for providing field resources, and to Mr Hồ Ngọc Lang and
Hồ Văn Đạo for their assistance in the field. The co-operation of the project staff, Đặng Văn Sơn, Trương Bá Vương,
Ðỗ Đăng Giáp, Trần Trọng Tuấn and Nguyễn Thị Mai Hương, is acknowledged. The author is also thankful to David
J. Middleton (SING) and to the anonymous reviewers for their constructive comments and language improvements to
this manuscript.

References
IUCN. (2012) The IUCN red List of threatened species: version 3.1. 2nd ed. Gland, Switzerland & Cambridge, UK: IUCN.iv+ 32pp.
Available from: (accessed 28 October 2016)
Luu, H.T., Pham, H.N., Tran, G., Ngo, T.T. D., Dinh, N.L. & Ton, T.M. (2015) Billolivia kyi (Gesneriaceae), a new species from Vietnam.
Annales Botanici Fennici 52: 362–364.
/>Middleton, D.J., Atkins, H., Luu, H.T., Nishii, K. & Möller, M. (2014a) Billolivia, a new genus of Gesneriaceae from Vietnam with five
new species. Phytotaxa 161: 241–269.
/>Middleton, D.J., Leong-Škorničková, J. & Nguyễn, Q.B. (2014b) A new species of Billolivia (Gesneriaceae) from Vietnam. Gardens’
Bulletin Singapore 66: 189–194.
Vũ, N.L., Phạm, H.N., Nguyễn, T.V. & Luu, H.T. (2015) Billolivia tichii (Gesneriaceae), a new species from Vietnam. Phytotaxa 219:
190–194.
/>
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