Zingiber vuquangense N.S. Lý, T.H. Lê, T.H. Tr

Lê, Th ị-Hương, Tr ịnh, Th ị-Hương, Ð ỗ, Ng ọc-Ðài, Nguy ễn, Vi ệt-Hùng & Lý, Ng ọc-Sâm, 2019, Zingiber vuquangense (Sect. Cryptanthium: Zingiberaceae): a new species from North central coast region, Vietnam, Phytotaxa 388 (4), pp. 295-300 : 297-300

publication ID	https://doi.org/ 10.11646/phytotaxa.388.4.5
persistent identifier	https://treatment.plazi.org/id/03A8CE33-6873-FFFD-ADCC-F91CFBFA1822
treatment provided by	Felipe
scientific name	Zingiber vuquangense N.S. Lý, T.H. Lê, T.H. Tr
status

Treatment

Zingiber vuquangense N.S. Lý, T.H. Lê, T.H. Tr View in CoL ịnh, V.H. Nguyễn & N.Đ. Đỗ, sp. nov. ( Figs. 1 View FIGURE 1 & 2 View FIGURE )

Zimgiber vuquangense is most similar morphologically to Z. cornubracteatum , but differs from the latter by smaller plant, longer ligules with lobes soon scarious when old, ragged and red-brown, longer petiole, lamina broadly elliptic to elliptic–ovate and glabrous, except densely pubescent along the below midrib, bract and bracteole pale yellow at base, brown-red distally, bright yellow corolla lobes, labellum pink-purple with pale yellow spots, yellow lateral staminodes with apex pink-purple and fruit ovoid.

Type: ― VIETNAM. Hà Tĩnh Province: Vũ Quang National Park, Phan wall, 18 º 17´20″N, 105 º 21´41″E, 106 m elev., 26 April 2015, Đỗ Ngọc Ðài ĐNĐ-568 (holotype VNM; isotypes P & HN) .

Perennial, non-stoloniferous, clump forming, rhizomatous herbs, 1.2–1.8 m tall. Rhizome fleshy, densely branched, (1.2–) 1.5–2 cm in diam., dull brown externally, tinted pinkish-white internally, none aromatic, covered with brown triangular scales; root tubers absent; scale 2–3 cm long, light brown externally, paler internally, glabrous, soon decaying. Leafy shoots 4–8 per plant, forming dense clumps, somewhat spreading or arching, each shoot consisting of 9–21 well-developed leaves at flowering, aggregated on upper 2/3 to ¾ of pseudostem; bladeless sheaths 3–4, 2–34 cm long, green with red tinge; leafy sheaths reddish to tinted red-green near the base, dark green distally, inconspicuously longitudinally striate, sparsely hairy when young, becomes glabrous with age, margin densely brown ciliate (brown hairs); ligules deeply bilobed to basal half, 1.2–3 cm long, green, conspicuously longitudinally striate, somewhat hairy, lobes 1–2 cm long, coriaceous, margin hairy, apex obtuse, soon scarious when old, ragged and rusty brown, persistent; petiole stiff, canaliculated, 2.5–4 cm long, less than 1.5 cm long on most basal and distal leaves, green, densely brown pubescent at pulvinus, pubescent distally; lamina broadly elliptic to elliptic–ovate, 26–50.8 × 9–14.7 cm, adaxially dark green, abaxially light green, glabrous except densely pubescent along below midrib, very strongly plicate, base rounded to obtuse, rarely cuneate, apex short acuminate to attenuate, secondary veins prominent above, sunken below, margin scattered hairs near the base. Inflorescences 1–2 per plant, radical, arising from the base of pseudostem, 7–15 cm long, usually with 2 flowers opening at a time; peduncle usually fully embedded in ground, 2.5‒11 × 1.1–1.5 cm, shortly pubescent, covered by 8–9 scales; basal scales triangular-ovate, 0.9–1.5 × 1.5–3 cm, upper scales oblong to obovate-oblong, 2–3.2 × 2.1–3.7 cm, base pale yellow, brown-red distally, apex retuse with short mucronate (mucro ca. 0.5 mm long), sparsely hairy at base, pubescent towards apex; spike ovoid-obovoid, 3.5––10 × 2.9–6.5 cm, composed of 26–30 loosely arranged bracts, each subtending a single flower, lower 2–3 sterile bracts; basal sterile bracts oblong, base slightly tapering, 2.3–2.8 × 3.1–3.9 cm, upper ones club-shaped [clavate] and attenuate, 2.8–3.2 × 1.2–2.7 cm, base pale yellow, brown-red distally, apex reflexed, exserted and incurved, tip rounded and mucronate with a mucro ca. 1 mm, margin ciliate, densely pubescent towards apex. Bracteoles oblong, 3.5–4.3 × 1.1–1.3 cm, brown-red at upper 1/3, pale yellow towards base, sparse hairs at base, densely pubescent distally, apex rounded, margin slightly serrate, ciliate. Flowers exserted from bracts, 7.8–8.4 cm long; calyx tubular, 16.5–17.5 mm long, clasping at base, translucent white, externally sparsely pubescent, with unilateral incision 7.5–8.5 mm long, apex with 2 acute tooth; floral tube 37–39 mm long, widening gradually towards apex, 7–8 mm wide at apex, cream at base, pale yellow towards apex, externally pubescent, internally pubescent at apex; dorsal corolla lobe triangular-ovate, 43–45 × 9–10 mm, pale yellow with semi-translucent veins, glabrous, apex acute, concave, slightly hooded; lateral corolla lobes narrowly triangular-ovate, 36–37 × 6–7.5 mm, pale yellow with semi-translucent veins, glabrous, apex acute, weakly concave at apex, deflexed at anthesis; labellum obovate, 38–41 mm long, 18–20 mm at widest point near the apex of labellum (25–30 mm broad, inclusive of lateral staminodes), pale yellow at base, pink-purple with small pale yellow spots, margin deflexed, slightly emarginate and undulate, glabrous, apex acute; lateral staminodes obovate to oblong, 20–22 × 8–11 mm, pale yellow with small pink-purple blotches at apex, semi-translucent veins, connate to labellum by apical 3/4, glabrous, apex rounded/obtuse. Stamen 30–32 mm long (unmanipulated); filament 2.5–3 mm long by ca. 3 mm wide, pale yellow, with very scattered short hairs; anther 15–17 mm long (crest not straightened), 3.5–4 mm broad, connective tissue pale yellow, glabrous; anther crest 15–17 mm (straightened), wrapped around stigma, light yellow with purple tinge towards apex, glabrous, tip bifid; anther thecae 14–15 mm long, dehiscing along the entire length. Epigynous glands two, subulate, 7–7.5 mm long, c. 1 mm in diam. at base, cream, apex acute. Ovary cylindrical, 7–7.5 × 3–3.5 mm, yellow-cream with white pubescence, trilocular with axile placentation; style 5.9–6.2 cm long, white, glabrous; stigma ca. 2 mm long, rounded, slightly thicker than style, white, ostiole front facing, ciliate. Infructescence ca. 11 cm long; peduncle ca. 5 × 1.5 cm, bract scales persistent, apical part composed of ca. 12 fruits; mature capsules sessile or pedicel 2 mm long, somewhat trigonous ovoid, 3.2–4 × 1.2–1.9 cm, light purple, sparsely pubescent, with accrescent bracteole 4–4.7 cm, apex with persistent floral tube 1.7–1.8 cm long, (6–)16–20 seeds per fruit; seeds 4–11 per locule, irregular obovoid, 4–5 × 3.5–4 cm, pink-red, surface irregular furrow, with sparsely echinate at apex; arils translucent white, ciliate.

Phenology: ―Flowering and fruiting: April–June.

Etymology: ―The specific epithet refers to the Vũ Quang NP where the new species was firstly discovered and collected.

Distribution and habitat: ―The new species is found from five localities in the provinces of Quảng Bình, Hà Tĩnh, Nghệ An, Ninh Bình and Phú Phọ in Vietnam. It grows along stream side, wet ground or hill slopes in secondary broad-leaved forest in Vũ Quang NP and Pù Hoạt NR at the altitude 70–600 m elev., and grows in lower primary evergreen broad-leaved tropical forest in Phong Nha-Kẻ Bàng NP at an altitude of 776–872 m elev. The three localities are distanced about 150 km from each other. It also found in Cúc PhƯƠng and Xuân SƠn NPs ( Fig. 2 View FIGURE ).

Conservation status:―Currently only a population which together consists of about 20 mature clumps in a total Area of Occupancy (AOO) of less than 550 km 2 on Vũ Quang NP, a population of about 10 mature clumps in a total AOO of less than 357 km 2 on Pù Hoạt NR, and a population of about 40 mature clumps in a total AOO of about 857 km 2 on Phong Nha-Kẻ Bàng NP were observed. There is no threat to these populations in those localities. The new species also occurred on Cúc PhƯƠng NP, Ninh Bình Province (AOO: 222 km 2) and Xuân SƠn NP, Phú Thọ Provnice (AOO: 150.5 km 2) based on the materials at the herbarium of the Vietnam Academy of Science and Technology (HN), but the number and size of the populations are not yet exactly known. It is expected that this species will be reported from other localities in near future. Based on currently available data we therefore provisionally assess this species as Data Deficent (DD) according to the IUCN Red list criteria (IUCN, 2012). Further exploration of the region is required.

Vernacular name and use: ―In the Thái langue (Cắm Muộn Commune, Quế Phong District, Nghệ An Province), the vernacular name of this species is locally called Có hủm and its grilled rhizomes are tied on throat to cure cough and cold.

Additional specimens examined (Paratype):― VIETNAM. Hà Tĩnh Province: Vũ Quang NP, Phan wall, 18 º 17´20″N, 105 º 21´41″E, 106 m elev., 17 July 2014, Lê Th ị HƯƠng, HƯƠng-134, 141 ( VNM), HƯƠng-570 (HN) ; ibidem, 01 May 2016, Lê Th ị HƯƠng, Nguyễn Vi ệt Hùng, Tr ịnh Th ị HƯƠng, HHH-387, 393 (HN). Qu ảng Bình Province: Qu ảng Ninh District , Tân Tr ạch Commune, Phong Nha –Kẻ Bàng NP, U Bò hill, 17 º 27´44″N, 106 º 22´51″E, 632 m elev., 16 August 2014, Đỗ Ngọc Ðài, Ðài-572 (HN, VNMN) ; ibidem, 17 º 28´47″N, 106 º 19´50″E, 735 m elev., 06 June 2017, Đỗ Ngọc Ðài, Ðài- 875, 883, 891 (HN, VNMN). Nghệ An Province: Quế Phong District, C ắm Muộn Commune, Pù Hoạt Natural Reserve , 19 º 49´25″N, 104 º 54´080″E, 610 m elev., 02 November 2017, Lê Th ị HƯƠng, HƯƠng-263 (HN). Phú Thọ Province: Xuân SƠn NP, 31 October 2001, PhƯƠng 4770 (HN!). Ninh Bình Province: Bống village, Cúc PhƯƠng NP, 16 October 1996, Nguyễn Qu ốc Bình, Nguyễn mạnh CƯƠng 35 (2 sheets, HN!) .

Notes: ― Zingiber vuquangense is most similar morphologically to Z. cornubracteatum Triboun & Larsen (2014: 60) , which is distributed in hill evergreen forest (800–1,100 m elev.) in Mae Hong Son, Northern Thailand ( Triboun et al., 2014), in the general habit, bract shape and lateral staminodes. However, the new species differs from Z. cornubracteatum by its smaller plant, longer ligules and petiole, leaf shape, colour of bract, bracteole and flower, and fruit shape (see Table 1).

Zingiber vuquangense was first discovered from Cúc PhƯƠng NP, Ninh Bình Province, in 1996 by Nguyễn Quốc Bình and Nguyễn Mạnh CƯƠng (HN). Subsequently this taxon was collected from Xuân SƠn NP, Phú Thọ Province, northern Vietnam in 2001 by Vũ Xuân PhƯƠng (HN). The plants exhibit the same characters of ligules, leaves and flowers but have long peduncles of inflorescences compared to those from Pù Hoạt NR, Vũ Quang and Phong Nha NPs. Moreover, the plants grow in Pù Hoạt NR and Phong Nha-Kẻ Bàng NP exhibiting small habit and small leaves compared to those from Vũ Quang NP and the remaining localities, respectively.