Additional specimens examined (paratypes):
CHINA. Yunnan: Nujiang Prefecture, Gongshan County, Dulongjiang, Kunzhongtu village, 27°47′46.04″N, 98°19′43.6″ E, alt. 1417 m, growing on trees near the river, 13 Feb. 2023, H. Jiang and Q.-C. Liao, 12004 (KUN!, YAF!); Kunming, a voucher from cultivated plants at Kunming Institute of Botany, CAS, 17 Feb 2023, J.-D. Ya BC230203, originally collected in northwest Yunnan: Gongshan county, Dulongjiang, subtropical evergreen seasonal rain forest, alt. 1200 m.
Conservation status : Cylindrolobus gaoligongensis is distributed in the northern Gaoligong Mountain Nature Reserve. We found some populations with abundant individuals during our field expeditions. The new species is considered as Least Concern (LC) according to the IUCN Red List category (IUCN 2023).
Supplementary andrevised descriptions ofCylindrolobus arunachalensis
Cylindrolobus arunachalensis (A. N. Rao) A. N. Rao in Bulletin of Arunachal Forest Research 26 (1&2): 82-110, 2010. - Eria arunachalensis Nageswara Rao in J. Econ. Tax. Bot. 21(3):711.1997. (Fig.2) (藏南柱兰)
Type: China, Xizang: Motuo, A. N. Rao 3018-A (orchid herbarium Tipi-Holotype); A. N. Rao 3018-B (CAL-paratype)
Description. Epiphytic herb. Roots terete, slender, pubescent,ca. 0.5‒1.5 mm thick. Rhizome inconspicuous. Stem clustered, terete, slender, 2‒5-leaved apically, covered by close-fitting sheaths, 15‒35 cm long, 3.0‒8.0 mm thick. Leaves lanceolate, acuminate, 6.0‒12.0 × 1.5‒3.5 cm. Inflorescences axillary, pubescent, borne on near the apical of the stem, 3.0‒4.5 cm long, 2 flowered; peduncle 1.0‒2.0 cm long; basal bracts 2, light brown, membranous, lanceolate, ca.1.1 × 0.4 cm; floral bracts yellowish green, fleshy, ovate-oblong, 1.2‒1.6 × 1.0‒1.2 cm, acute, concave, base externally sparsely brown tomentose. Flowers white; peduncle and ovary ca. 1.0‒1.7 cm long, densely brown tomentum. Sepal externally densely brown tomentum; dorsal sepal oblong-lanceolate, subacute, 5 veined, ca. 1.6 × 0.5 cm; lateral sepals falcate-ovate, acute, 7 veined, ca. 1.4 × 1.0 cm, base adnate to column foot form a subglobose and obtuse mentum; petals lanceolate, slightly oblique, acute, 3 veined, ca. 1.4 × 0.5 cm; labellum yellowish green, obovate in outline, ca. 1.0 × 0.7 cm, 3-lobed; lateral lobes suberect, subovate, ca. 0.6 × 0.3 cm, front margin densely purple red long glandular hairs, mid-lobe reniform, ca. 4.0 × 1.5 mm, apex emarginated, margin densely purple red long glandular hairs; disk with 3 lamellae, central lamellae extending to mid-lobe and densely yellow glandular hairs, lateral 2 reddish brown and running from the base of disk to central lamellae, densely purple red glandular hairs, thickened and glabrous in apical. Column semiterete, ca. 7.0 mm long, ventrally narrow winged; foot U-bent, ca. 1.0 cm. Anther cap hemispherical, ca. 1.6 × 1.6 mm, pollinia 8, yellowish-white, compressed rectangular, anterior ca. 0.8 × 0.7 mm, posterior 4 smaller. Fl. January-February.
Phenology: Flowering from January to February.