Ophiopogon tiandengensis H.Z. Feng, C.X. Peng & Q.W. Lin, 2025

Feng, Hui Zhe, Peng, Cai Xia, Tan, Kun & Lin, Qin Wen, 2025, Identity of Ophiopogon tonkinensis and O. ogisui, with a new species O. tiandengensis from Guangxi, China, Phytotaxa 700 (1), pp. 45-59 : 54-57

Ophiopogon tiandengensis H.Z. Feng, C.X. Peng & Q.W. Lin , sp. nov. Figs. 6 , 7 & 8 .

Type: — CHINA. Type herbarium specimen prepared in 22 May 2023 from plants cultivated in Garden of IBSC, C. X. Peng 0373 (holotype: IBSC9301377 !; isotype: IBSC9301376 !), originated from Guangxi, Chongzuo, Tiandeng, Fuxin, Wanxiu, the vicinity of Buxiu, alt. 224 m.

Diagnosis: — Ophiopogon tiandengensis resembles O. tonkinensis , but can be readily distinguished from the latter by its blade obovate, smaller in size, pedicel articulated in the middle, inflorescence ca. 25 flowered, flower campanulate and lobes not reflexed but somewhat divergent distally; and flowering in May–July (vs. in October to December).

Description: —Herbs, perennial, evergreen. Rhizome very short, ca. 1.5 cm long, 0.6 cm in diam. Roots ca.

4 mm in diam., pubescent. Leaves basal or tufted glabrous; petiole 3–5 cm long, ca. 2.5 mm in diam., pale green; blade obovate, 6.5–9.1 cm long, 2.2–3.2 cm broad, entire, leathery, adaxially green, abaxially pale green with 23–28 whitish green longitudinal streaks, basally cuneate and asymmetric, acute at apex. Cataphyll membranous, quickly withering, brown. Scape 5–6 cm long, green, glabrous. Inflorescence terminal, reduced panicle 5.5–8 cm long, erect, green, glabrous, ca. 25 flowered, in clusters of 2 or 3; outer bract ca. 4 mm long, boat-shaped, centrally pale green, marginally purple, inner bract 0.8–1.5 mm long. Flowers hermaphroditic, campanulate, in clusters colate, in clusters of 1 or 2, facing downward. Pedicel articulated, 4.5–8.0 mm long; portion below articulation ca. 2–3 mm long, dark purple; portion above articulation 2.5–5.0 mm long. Perianth ca. 5.5 mm long, ca. 6.5 mm in diam., purplish; lobes 6, oblong to elliptic, apex reflexed, 4.5–5 mm long, 2–2.5 mm broad. Stamens 6, ca. 2 mm long, introrse; filaments free, ca. 1mm long, ca. 0.5 mm broad, pale green; anthers ovoid, ca. 0.7 mm long, cream. Ovary half inferior, 3 locules at distal part and septum disappears thus locules at base. Style 4.5 mm long, slender, white, exceeding perianth by 1 mm at maturity. Seeds spherical, 1.3 cm in diam.

Phenology: —Flowering from May to July.

Distribution and habitat: — Ophiopogon tiandengensis is only distributed in the damp valleys on the shady slopes of limestone hills in the southwestern part of Guangxi. In addition to the type locality in Tiandeng County, the species is also distributed in places such as Longzhou County, Jingxi County, Daxin County (see Additional specimens examined).

Etymology:—The specific epithet tiandengensis is derived from Tiandeng County, where it was discovered. The Chinese name for Ophiopogon tiandengensis is provided here as “ 天Şȁẖặ ” (Tiān děng yán jiē cǎo), “ ȁ ẖặ ”is the common Chinese name for the genus Ophiopogon , while “ 天Ş ” directly translated the specific epithet tiandengensis .

Conservation status:—Based on field surveys, the species is widely distributed in southwestern Guangxi, but each population is relatively small. Although some populations are located within protected areas, this plant is sold online as a small bonsai and has high ornamental value, leading to extensive collection that has caused a rapid decline in both population and individual numbers. And its population is estimated to decrease by 50% in the next ten years. According to the IUCN's A2c (IUCN 2024) standard, it is rated as Endangered (EN).

Note: — Ophiopogon tiandengensis is similar to O. tonkinensis , but its blades obovate to suboblong (vs. oblanceolate-oblong), 6.5–9.1× 2.2–3.2 cm (vs. 8.3–23.5 × 2.0– 6.3 cm), petiole 3–5 cm long (vs. 8–32 cm long), pedicel portion above articulation 2.5–5 mm long (vs. 11–19 mm long) and articulated in the middle (vs. articulated in the lower), inflorescence ca. 25 flowered (vs. ca. 51 flowered), flower campanulate and lobes top not reflexed but somewhat divergent distally (vs. urceolate and lobes top reflexed) and flowering from May–July (vs. in November).

In addition, Ophiopogon tiandengensis is somewhat similar to O. sinensis Y. Wan & C.C. Huang (1987: 398) ( Figs. 10 ) with their perianth lobes white to light purple and being somewhat divergent distally. O. sinensis was described on the basis of a single specimen, C.C. Huang 12252 (GXMG0039018!), type herbarium specimen prepared from cultivated plant in GXMG, Nanning, Guangxi, China and origin unknown. Based on Chen & Tamura (2000), Yang & Li (1990) and Yang (1997), this species also distributed in Southeastern Yunnan. In the protologue, the author stated that O. sinensis similar to O. bockianus Diels (1900: 254) but differing by the following characters: leaves oblanceolate-oblong, 3.2–4 cm wide; scape shorter (ca. 14 cm long); pedicels longer (12–15 mm long); anthers lanceolate (ca. 4.5 mm long), initially coherent but becoming discrete. Thus, there are significant differences between O. tiandengensis and O. sinensis . The leaves of O. sinensis are oblanceolate-oblong to suboblong and petiolate indistinctly. Additionally, the anthers are lanceolate and ca. 4.5 mm long. The most critical difference is that the anthers of O. tiandengensis are initially connate, later free. The differences in these three species are mentioned in Table 1.

Additional specimens examined:— Ophiopogon tiandengensis . CHINA. Guangxi: Longzhou County, 20 July 2009, R. H. Jiang, W. H. Wu & D.X. Nong H09218 ( IBK00216917 !) ; Longzhou County, 27 April 2013, L. Wu & Y. Tong 3481 ( BNU0033173 !) ; Longzhou County, 7 May 2014, Z. G. Yan , S. C. Yao & S. G. Wei 451423140507004 LY ( GXMG0128310 !) ; Longzhou County, 28 April 1980, Nonggang Exped. 11823 ( IBK00139109 !) ; Longzhou County, 1 November 1979, Nonggang Exped. 11489 ( IBK00139110 ) ; Longzhou County, 3 November 1979, Nonggang Exped. 20733 ( IBK00185093 !) ; Longzhou County, 7 July 2011, Y. S. Huang & Y. B. Liao LZ622 ( IBK00205600 !). Jingxi County, 8 August 2009, W. B. Xu & W. H. Wu 091674 ( IBK00216916 !). Daxin County , 20 May 2008, Zhongzhilian 0822 ( IBK00281506 !) .

Ophiopogon tonkinensis . CHINA. Guangxi: Introduced in Guangxi Medicinal Botanical Garden , 9 November 1997, X. C. Huang 7375 ( GXMG0039065 !). Longzhou County, 9 November 1956, Z. J. Li 3142 ( IBSC0644273 !) ; Longzhou County, 2 November 2024, H. Z. Feng et al. 202411022 ( SYS!) ; Longzhou County, 12 November 2024, Ting Xu et al. 2321 ( SYS!). Ningming County , 23 October 1958, Z. Q. Zhang 13057 ( IBK00139097 !) . VIETNAM. Northern Vietnam: limestone area allied to Chinese border. Terrestrial herb in primary and secondary evergreen broad-leaved shady lowland forests on limestone at elevations about 400–500 m a.s.l, 8 November 2014, Averyanov , L. Vladimirovich & N. M. Duc Averyanov s.n. ( LE01049841 photo!). Lang Son province: Quan Ba District , Can Ty Commune , Sin Suoi Ho Village , around point 23.09566ºN 105.02142ºE. Very steep mountain slopes composed of solid highly eroded karstic limestone at elevation 800–1000 m a.s.l. Remnants of primary evergreen broad-leaved and coniferous (with Calocedrus rupestris and Xanthocyparis vietnamensis) humid forest. Terrestrial herb in shady place among rocks. 11 October 2019, Averyanov, L. Vladimirovich, K. S. Nguyen, M. T. Viktorovna VR 1551 ( LE01070147 photo! & LE01067025 photo!). Lao Cai province: Sapa, 21 October 1960, A. L. Takhtajan 385 ( LE01049927 photo!; LE01049923 photo! & LE01049848 photo!). Ninh Binh province: Thanh Yen District , Sanh Village , Cuc Phuong National Park , 1 January 2001, N. M. Cuong, D. T. Kien & M. V. Sinh NMC1300 ( P01850925 photo!). Ha Giang province: Quan Ba District , Bat Dai Son Nature Reserve , Bat Dai Son Commune, Pai Chu Phin Village , around point 23º07ʹ54ʺN 104º59ʹ24ʺE, elev. 1000–1200 m a.s.l., karstic, highly eroded mountains composed of solid marble-like limestone, primary evergreen broad-leaved and coniferous (with Pseudotsuga sinensis) humid forest on steep rocky slopes near mountain tops. Perennial herb up to 25 cm tall, occasionally on the ridge and near mountain top. 21 October 2022, V. D. Nguyen et al. VN-US-008 ( LE01123895 photo!) . TONKIN: November 1885, B. Balansa 280 ( P01850926 photo!) ; B. Balansa 281 ( P01850927 photo! & P01850928 photo!) .

Figures

FIGURE 6. Ophiopogon tonkinensis. Northern Vietnam, low limestone hills, cultivated in Hanoi, 8 Nov 2014, M.D. Nguyen & L. Averyanov s.n. (LE01049841 photo!);

FIGURE 7. Ophiopogon tiandengensis. A & B. flowering plants; C. fruiting plants in habitat; D & E. Plant. F. Base of plant. G–K. Inflorescence; L. Flower, views from side. M. Longitudinal section of flowers. N. Flower, views from side, with lobes removed. O. Flower, views from side. P & Q. Flower, front view. R & T. Flower, views from side, with some lobes removed. S & U. Stamen. V. Flower, views from side, with some lobes and stamens removed. W. Style. X. Ovary, longitudinal section.Y. Longitudinal section of flowers. Z. Roots.

FIGURE 8. Ophiopogon tiandengensis sp. nov.A. flowering plant; B. Blade; C. Flower, side view, with two bracts; D. Flower, side view, with 3 tepals removed; E. Tepals; F. Pistil, F1, style; G. Stamens. All drawn from the holotype.

FIGURE 10. Holotype of Ophiopogon sinensis.