Corresponding author: Nguyen Van Ngoc (
Academic editor: Norbert Holstein
Three new species,
Ngoc NV, Binh HT, Nagahama A, Tagane S, Toyama H, Matsuo A, Suyama Y, Yahara T (2021) Morphological and molecular evidence reveals three new species of
The phylogenetic approach has become a widespread and efficient way to identify and delimit species, but there is only one study for
Bidoup-Nui Ba National Park (Fig.
Type locality of the new species (Black dots): L1:
During our floristic research in Bidoup-Nui Ba National Park from 2015 to present, we found some individuals of the genus
In the present study, we conducted botanical inventories in Bidoup-Nui Ba National Park and the other protected areas in Vietnam and collected a total of 63 samples consisting of 23 species including sixteen samples of three unknown species. Five samples of
List of vouchers specimen that were used in this study.
Species | Vouchers | Localities |
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Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
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Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
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Bidoup-Nui Ba NP | |
Dong Nai NR | ||
|
Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
|
Hoang Lien NP | |
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Hon Ba NR | |
|
Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
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Bidoup-Nui Ba NP | |
|
Ngoc Linh NR | |
Bidoup-Nui Ba NP | ||
|
Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
|
Bidoup-Nui Ba NP | |
|
Vu Quang NP | |
|
Vu Quang NP | |
|
Bidoup-Nui Ba NP | |
Bach Ma NP | ||
Bidoup NP | ||
Pu Mat NP |
NP = National Park; NR = Nature Reserve.
We compared morphological traits of three unknown species with those of related species using taxonomic literature (
The ImageJ software (
Leaf pieces were dried using silica-gel in the field, and DNA was isolated with the CTAB method (
A total of 50 samples of 22 species of
Phylogenetic analyses were conducted using maximum likelihood method on SNPs data set. The model of sequence evolution was set to GTR+G as selected by jMrModeltest 2.1.10 (
After the morphological examination and taxonomic review in
The comparisons of mean (X) and standard deviation (SD) value of the leaf blade and cupule size between
Parameters (cm) |
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X | SD | n | X | SD | n | X | SD | n | |
Leaf blade length | 9.74 | 1.12 | 23 | 13.66 | 1.89 | 22 | 10.76 | 2.01 | 20 |
Leaf blade width | 4.5 | 0.59 | 23 | 4.41 | 0.51 | 22 | 3.46 | 0.53 | 20 |
Leaf blade aspect ratio | 2.17 | 0.15 | 23 | 3.11 | 0.36 | 22 | 3.1 | 0.31 | 20 |
Leaf blade circularity | 0.71 | 0.03 | 23 | 0.58 | 0.05 | 22 | 0.55 | 0.05 | 20 |
Petiole length | 0.5 | 0.1 | 23 | 1.89 | 0.23 | 22 | 0.81 | 0.14 | 20 |
Cupule high | 0.98 | 0.19 | 27 | 0.64 | 0.06 | 22 | 0.88 | 0.15 | 16 |
Cupule diameter | 2.47 | 0.2 | 27 | 1.58 | 0.11 | 22 | 2.17 | 0.13 | 16 |
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Leaf blade length | 14.83 | 1.6 | 22 | 19.4 | 3.45 | 22 | 20.39 | 3.44 | 20 |
Leaf blade width | 5.3 | 0.84 | 22 | 8.06 | 1.48 | 22 | 8.84 | 1.66 | 20 |
Leaf blade aspect ratio | 2.86 | 0.34 | 22 | 2.41 | 0.17 | 22 | 2.32 | 0.16 | 20 |
Leaf blade circularity | 0.59 | 0.06 | 22 | 0.7 | 0.04 | 22 | 0.69 | 0.04 | 20 |
Petiole length | 1.42 | 0.19 | 22 | 1.4 | 0.14 | 22 | 2.11 | 0.36 | 20 |
Cupule high | 1.10 | 0.18 | 21 | 1.23 | 0.14 | 28 | - | - | - |
Cupule diameter | 2.99 | 0.28 | 21 | 2.24 | 0.19 | 28 | - | - | - |
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Leaf blade length | 10.81 | 1.93 | 29 | 8.42 | 2.26 | 22 | 7.49 | 1.32 | 25 |
Leaf blade width | 3.26 | 0.6 | 29 | 2.97 | 0.95 | 22 | 2.39 | 0.32 | 25 |
Leaf blade aspect ratio | 3.33 | 0.33 | 29 | 2.9 | 0.4 | 22 | 3.13 | 0.33 | 25 |
Leaf blade circularity | 0.49 | 0.04 | 29 | 0.57 | 0.07 | 22 | 0.5 | 0.05 | 25 |
Petiole length | 2.59 | 0.49 | 29 | 0.74 | 0.12 | 22 | 1.3 | 0.23 | 25 |
Cupule high | 1.01 | 0.15 | 25 | 0.57 | 0.05 | 19 | 0.86 | 0.26 | 18 |
Cupule diameter | 2.06 | 0.28 | 25 | 1.31 | 0.14 | 19 | 1.63 | 0.18 | 18 |
Differences between the species for morphological characters and their levels of significance determined by TukeyHSD Test.
Comparisons | Leaf blade length | Leaf blade width | Aspect ratio | Circularity | Petiole length | Cupule high | Cupule diameter | |||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
diff. |
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diff. |
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diff. |
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diff. |
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diff. |
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diff. |
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diff. |
|
|
3.92 |
|
-0.09 | 0.85 | 0.93 |
|
-0.13 |
|
1.39 |
|
-0.35 |
|
-0.89 |
|
|
1.01 | 0.13 | -1.04 |
|
0.90 |
|
-0.16 |
|
0.31 |
|
-0.1 | 0.07 | -0.29 |
|
|
4.57 |
|
2.76 |
|
-0.45 |
|
0.11 |
|
-0.02 | 0.97 | 0.13 |
|
-0.75 |
|
|
5.56 |
|
3.53 |
|
-0.09 |
|
0.09 |
|
0.69 |
|
- | - | - | - | |
-2.39 |
|
-0.29 | 0.26 | -0.43 |
|
0.08 |
|
-1.85 |
|
-0.44 |
|
-0.75 |
|
|
-3.33 | 0 | -0.58 |
|
-0.20 | 0.09 | 0.02 | 0.55 | -1.29 |
|
-0.15 |
|
-0.43 |
|
Note: diff. = mean difference;
The Maximum likelihood tree based on data set of 4962 genome-wide SNPs strongly supports two sister clades, clade 1 and 2, with 100% bootstrap value (Fig.
Maximum likehood tree of three new species (
The morphological comparison and phylogenetic analysis provided evidence of the validity of three new species.
Although we could not collect any specimens of
Vietnam. Lam Dong Province: Bidoup-Nui Ba National Park, in hill evergreen forest dominated by the species of
Evergreen tree, up to 27 m tall. Branches yellowish green when young, turning greyish brown when old, glabrous, sparsely lenticellate. Terminal and lateral buds ovoid, up to 7 mm long. Leaves alternate; petiole 0.3–0.4 cm long, glabrous; blade elliptic to oblong-elliptic, obovate-elliptic, 6–11.6 × 2.8–5.3 cm, coriaceous, glabrous, glossy green on both surfaces, apex acuminate or attenuate, acumen up to 0.9 cm long, base cuneate, rarely obtuse, margin completely entire, midrib prominent on both surfaces, secondary veins 10–12 pairs, prominent abaxially, at an angle of 55–70° from the midrib, tertiary veins scalariform-reticulate, visible abaxially. Inflorescences not seen. Infructescences a woody spike, 8.4–11.5 cm long. Cupules sessile, usually in cluster of 3, fused at the base each other, depressed obconical or saucer-shaped, 0.71–1.40 cm high, 2.13–2.80 cm in diam., enclosing 1/4–1/3 of the nut, pubescent with short grayish indumentum outside; wall woody, ca. 2 mm thick, with brown triangular scales outside, the scales up to 4 × 4 mm, imbricate, arranged in 3 or 4 interrupted concentric rings. Nut broadly ovoid-conical to depressed ovoid-globose, 1.5–1.6 cm high, 2.1–2.3 cm in diam., glabrous, brown to blackish brown; basal scar slightly concave, 1.4–1.9 cm in diam.
Unknown. Fallen fruits were collected in February.
Vietnam (Khanh Hoa and Lam Dong provinces) (Fig.
The specific epithet is derived from the type locality, Bidoup-Nui Ba National Park, Lam Dong Province, Vietnam.
Dé đá Bidoup
Vietnam. Lam Dong Province: Bidoup-Nui Ba National Park; 1602 m elev.,
Critically Endangered (
Vietnam. Lam Dong Province, Bidoup-Nui Ba National Park: Cong Troi, at edge of evergreen forest, roadside, 1752 m elev.,
Evergreen tree, up to 25 m tall. Twigs blackish gray, glabrescent. Stipules caducous, not seen. Leaves alternate; petioles 1.1–1.8 cm long, glabrous; blades broadly elliptic, 12–18 × 4.2–7.2 cm, coriaceous, glabrous on both sides, apex acuminate, acumen 0.7–1.2 cm long, base acute to cuneate, margin entire, midrib flat or slightly prominent adaxially, strongly prominent abaxially, yellowish
Flowers were collected in December and mature fruits were collected from June to July.
Vietnam (so far known only from Mt. Cong Troi and Mt. Langbiang of Bidoup-Nui Ba National Park, Lam Dong Province). (Fig.
The specific epithet is derived from the type locality, Mt. Cong Troi of Bidoup-Nui Ba National Park, Lam Dong Province, Vietnam.
Dé đá Công TrÓi.
Vietnam. Lam Dong Province: Bidoup-Nui Ba National Park, Cong Troi area; 1750 m elev.,
Critically Endangered (
Vietnam. Lam Dong Province, Bidoup-Nui Ba National Park, Hon Giao, at edge of evergreen forest, roadside, 1580 m elev.,
Evergreen tree, up to 25 m tall. Twigs blackish gray, glabrescent, densely lenticellate. Stipules narrowly triangular, ca. 5 × 1 mm, densely covered with indumentum abaxially, almost glabrous adaxially. Leaves alternate; petioles 1.7–3.5 cm long, glabrous; blades narrowly elliptic to lanceolate, 7.6–14.7 × 2.3–4.6 cm, coriaceous, glabrous adaxially, covered with adherent waxy scales abaxially, apex acuminate, acumen up to 1.5 cm long, base attenuate and decurrent on petiole, margin entire, midrib flat or slightly prominent near base adaxially, prominent abaxially, greenish yellow
Young male flowers and mature fruits were collected in May and June.
Vietnam (so far known only from Hon Giao area of Bidoup-Nui Ba National Park, Lam Dong Province). (Fig.
The specific epithet is derived from the type locality, Hon Giao area of Bidoup-Nui Ba National Park, Lam Dong Province, Vietnam.
Dé đá Hòn Giao.
The new species is narrowly endemic to Hon Giao area of Bidoup-Nui Ba National Park, Lam Dong Province. During our floristic expedition from 2015 to present, we found only five mature individuals of
Vietnam. Lam Dong Province: Bidoup-Nui Ba National Park, Hon Giao, 1574 m elev.,
The authors thank the colleagues from the Bidoup-Nui Ba National Park for their help in collecting samples, and the directors and staff of the following herbaria ANDA, BKF, DLU, FOF, HN, HNL, KAG, KYO, P, and VNM for allowing us to examine their collections. This research is funded by Vietnam National Foundation for Science and Technology Development (NAFOSTED) under grant number 106.03-2018.325.