Campanulorchis thao (Gagnepain) Chen & Wood (2009: 346)

Vo, Doan Trung, Averyanov, Leonid, Maisak, Tatiana, Canh, Nguyen Van, Nguyen, Huu Cuong, Dang, Minh Quan, Dang, Van Son, Truong, Quang Tam & Vuong, Truong Ba, 2022, Taxonomic treatment of the genus Campanulorchis (Orchidaceae), Phytotaxa 561 (2), pp. 173-182 : 179-180

2. Campanulorchis thao (Gagnepain) Chen & Wood (2009: 346) . ( Fig. 1B , 3 ).

≡ Eria thao Gagnepain (1950: 503) .

Type: — VIETNAM. Hue Province , Bach Ma National Park “...Annam: sommet du Nin Bach Ma, station d’altitude un peu au sud de Huê..”, 1938, Polane, E. 27593 (photo, MNHN-P-P00403730, http://coldb.mnhn.fr/catalognumber/ mnhn/p/p00403730!) .

= E. bulbophylloides Tang & Wang (1974: 42) , nom. illeg. (non Schweinfurth 1936: 24). Type: — CHINA. Hainan: Yang Hsien ; 19. III. 1933, Leg. C. Wang 34749 (type not located).

= E. thao var. wlodarczykii Roeth (2010: 43) . Type: — VIETNAM. cultivated in horticulture in Grossräschener Orchideen by H-Joachim Wlodarczyk, 2009, Roeth, J., HAL 107662 (type not located).

Description: —Creeping epiphyte. Leaves petiolate; petiole short; leaf blade broadly lanceolate to narrowly elliptic, grassy green, (5)6–14(16) cm long, (1.2)1.5–2.2(2.8) cm wide, glabrous on both sides. Peduncle densely pale brown tomentose, (1.2)1.5–2(2.5) cm long; 1-flowered; floral bract very small, triangular; pedicel and ovary densely pale brown tomentose, 5.5–6 mm long. Flowers not widely opening, sepals and petals pale yellow, lip pale yellow with reddish brown tint. Sepal s subsimilar, narrowly ovate to ovate, ca. 2 cm long, ca. 8 mm wide, obtuse to acute, densely tomentose outside, glabrous inside. Petals glabrous, obovate-rhomboid, ca. 2 cm long, 5–6 mm wide, slightly oblique, acute. Lip ca. 2 cm long, 3-lobed; median lobe ovate, 9–10 mm long, 4–5 mm wide, acute; side lobes narrowly ovate, ca. 1 cm long, 2 mm wide, acute, erect, oblique; the disc with 3 keels; lateral keels clavate, running from base of lip to base of side lobes; median keel coming from the lip base to apex of median lobe. Column ca. 8 mm long, glabrous; stelidia triangular, obtuse; stigma obscurely rectangular, anther cap hemi globular, column foot ca. 4 mm long. Fruit erect, obconoid, hairy to 2.2 cm long, 0.5–0.7 mm in diameter.

Habitat and phenology: —Found in lowland, submontane and montane evergreen, broad-leaved, mixed and coniferous forests on any kind of parental rocks at elevations of 300–2100 m a.s.l. Flowers in November–March.

Distribution: — LAOS (Khammouane and Saravan Provinces), VIETNAM (Provinces Bac Kan, Dak Lak, Gia Lai, Ha Tinh, Hoa Binh, Kon Tum, Lam Dong, Lao Cai, Nghe An, Ninh Binh, Phu Tho, Quang Binh, Quang Tri, Son La, Thanh Hoa, Thua Thien – Hue, and Vinh Phuc), S CHINA (Hainan).

Notes: — The species has at least 50 documented locations in Vietnam, one in Hainan and two in Laos. The discovered locations in Laos reported here represents new national record of this species in Laos. These locations are Saravan Province , Sa Mouay District , Ta Oy Village , 4 March 2013, L. Averyanov et al., LA-VN 153 (LE01068950 https://en.herbariumle.ru/?t=occ&id=40768) and Khammouane Province, Boualapha District , Nong Seng Village , 4 May 2018, L. Averyanov et al., AL 652 (LE01048821 https://en.herbariumle.ru/?t=occ&id=120).

Specimens examined: —Studied specimens from Eastern Indochina are listed and available in Herbarium LE database by the link: https://en.herbariumle.ru/?t=occ&s=campanulorchis%20thao&f=main_identification.

Figures

FIGURE 1. Distribution of Campanulorchis species. A. Campanulorchis pulverulenta. B. C. thao. C. C. globifera. D. C. longipes. Map compiled by Truong Ba Vuong and L. Averyanov.

FIGURE 3. Campanulorchis thao. A. Flowering plants. B. Pseudobulb with flower. C. Young and mature pseudobulbs with basal bracts. D. Young pseudobulb. E. Young pseudobulb and flower. F. Pseudobulb bract. G. Peduncle and flower, side view. H. Pedicel, ovary and flower bud, side view. I. Peduncle, floral bract, pedicel and ovary. J. Floral bract, pedicel and ovary. K. Flattened flower, lip removed. L. Lip, side and frontal view. M. Column, frontal and side views. Photos and design by L. Averyanov, specimens L. Averyanov et al., HAL 12275 https://en.herbariumle.ru/?t=occ&s=HAL%2012275&f=%5Ball%5D.