Zeuxine drukyulensis P.Gyeltshen, K.Rabgay & Kumar, 2025

Gyeltshen, Phub, Rabgay, Kinley, Tobgay, Kezang & Kumar, Pankaj, 2025, Zeuxine drukyulensis (Orchidaceae), a new jewel orchid from Bhutan Himalaya, Phytotaxa 690 (1), pp. 123-129 : 124-126

publication ID	https://doi.org/10.11646/phytotaxa.690.1.11
persistent identifier	https://treatment.plazi.org/id/19657F38-FFCC-FF92-FF7D-FC20A4B6FC8A
treatment provided by	Felipe
scientific name	Zeuxine drukyulensis P.Gyeltshen, K.Rabgay & Kumar
status	sp. nov.

Treatment

Zeuxine drukyulensis P.Gyeltshen, K.Rabgay & Kumar , sp. nov.

Zeuxine drukyulensis is most similar to Z. nervosa and Z. rolfeana but can be differentiated based on shorter labellum, 5.5–6.5 mm long in new species (vs. longer, 0.8–1.1 cm long, in Z. nervosa , shortest and 4.0– 5.5 mm long in Z. rolfeana ); widest hypochile, 2.0– 2.2 mm long, 3.5–4.5 mm wide in new species (vs. wider, 2.8–3.2 mm long, 3.0– 3.5 mm wide in Z. nervosa and narrowest, 1.3–1.8 mm long, 1.3–2.0 mm wide in Z. rolfeana ); large mesochile, 2.0– 2.1 mm long, 1.4–1.6 mm wide in new species (vs. largest, 2.5–4.0 mm long, 2.0– 2.5 mm wide in Z. nervosa and smallest, 0.6–1.0 mm long, 1.0– 1.3 mm wide in Z. rolfeana ); shorter column, 1.0–2.0 mm in new species (vs. longest, up to 4.0 mm in Z. nervosa and shorter, 1.0– 1.5 mm in Z. rolfeana ); column with 4 wings in new species (vs. 2 wings in Z. nervosa and 4 wings in Z. rolfeana ).

Type:— BHUTAN. Punakha District: Goenshari Block, Rimchu area, 1359 m elevation, 17 March 2024, P.Gyeltshen, K.Tobgay & K.Rabgay 262 (holotype THIM! [ THIM 22882!]). Fig. 1 View FIGURE 1 .

Description:—Terrestrial herbs, 10–30 cm tall. Rhizome 5–35 cm long, 2.0– 3.5 mm thick, pale green, creeping, terete, rooting at nodes. Roots, pale brown, fleshy, with minute root hairs. Stem 10–15 cm long, 2.5–3.5 mm thick, brownish green, decumbent at base, erect above, unbranched, glabrous, with few membranous sheaths formed by withered leafbases. Leaves 4–5, crowded near apex, glabrous; petiole 5–8 mm long, sheathing at base; lamina ovate-lanceolate, 2.0–5.3 x 1.2–2.2 cm, obtuse at base, acute to acuminate at apex, uniformly green, 3-veined. Inflorescence racemose, terminal, sub-densely up to 10-flowered, greenish brown, pubescent; peduncle 6–40 cm long, with 2 sheathing bracts; sheathing bracts ovate-lanceolate, 10.0–15.0 × 3.5–4.5 mm, pale reddish-orange, clasping, apex narrowly acuminate, pubescent, 3-veined; floral bracts ovate-lanceolate, 1.0–1.2 × 0.4–0.5 cm, exceeding the ovary, apex narrowly acuminate, pubescent abaxially, pale reddish-orange, 3-veined. Flowers 7–9 mm across, green, resupinate. Pedicel and ovary, sub-fusiform, 7–10 mm long, twisted, green, pubescent. Sepals free, green; dorsal sepal sub-triangular, 5–6 × 3–4 mm, apex acute, sparsely pubescent abaxially; lateral sepals oblong-ovate, 6–7 × 4.0– 4.1 mm, spreading, apex obtuse, margin incurved, sparsely pubescent abaxially. Petals obliquely oblong-ovate, 5–6 × 3–4 mm, green with white apex portion, glabrous, abruptly apiculate at one side at apex, 1-veined. Labellum 5.5–6.5 mm long; hypochile saccate, ca. 2.0–2.2 × 3.5–4.5 mm, pale white with greenish tinge, with 3 filiform glands on each side; mesochile oblong, 2.0–2.1 × 1.4–1.6 mm, margin incurved, pale white with greenish tinge adaxially; epichile 2-lobed, lobes sub-orbicular, 2.0–2.2 × 2.5–3 mm, greenish-yellow with white tinge in the middle. Column 1–2 mm long, white, with 4 wings; outer wings, obliquely oblong or deltoid, c. 1 mm long, white; inner wings oblong, ca. 1.5 mm long, inserted inside the hypochile of labellum, thick; rostellum 2.5–3.0 mm long, white. Stigma lobes 2, oblong, dull white. Anther cap ca. 2 × 1 mm, pale brown. Pollinia 2, obclavate, 1.5–2.0 mm long, pollinarium 3.5–4.5 mm long, sectile, creamy white; stipe oblong, 1.0– 1.2 mm long, bifurcated at base, constricted near middle, golden yellow; viscidium sub-triangular, 1.3–1.5 mm long, semi-transparent.

Phenology: —Flowering in March–April.

Distribution and Habitat: — Zeuxine drukyulensis is currently known only from two sites, Punakha and Wangdue Districts in western Bhutan. Both sites have similar habitat conditions. The new species is a terrestrial orchid that grows among the leaf litter in the warm broadleaved forest at 1350 m elevation.

Etymology: —The specific epithet ‘ drukyulensis ’ refers to Drukyul, a name by which local people like to call Bhutan. It means ‘the land of the Thunder Dragon’, where the type specimen is collected from.

Conservation Status: — Zeuxine drukyulensis is known from two locations, Rimchu under Goenshari Block in Punakha district and Kamina area under Daga Gewog in Wandgue District. We observed only a single individual at Kamina and around 10 individuals at Rimchu area. The Area of Occupancy (AOO) is estimated as 12 km 2 using GeoCAT ( Bachman & Moat 2012). The area is visited by people residing nearby and there are chances of threat due to trampling by cattle. However, so far there is no direct threat to the habitat of this species observed. The species is also likely to occur in similar habitats with similar vegetation composition and geographical range. Therefore, further survey and exploration are needed is need in adjacent areas to confirm its distribution, area of occupancy, population size and threats. Attributable to inadequate information available to assess its conservation status, we propose the status as Data Deficient (DD) according to the IUCN Standards and Petitions Committee (2024).

Notes:— Zeuxine drukyulensisis shows morphological affinities with Z. nervosa and Z. rolfeana . However, they can be easily distinguished based on both the morphology and colour of flowers. The proposed new species is closer to Z. rolfeana than Z. nervosa due to sharing similar 4-winged column characters. Detailed morphological comparisons between the species are provided in the Table 1.