Campanulorchis pulverulenta, (Guillaumin) Ponert (2017: 94)

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 : 174-179

1. C. pulverulenta (Guillaumin) Ponert (2017: 94) . ( Fig. 1A , 2 ).

≡ Eria pulverulenta Guillaumin (1955: 691) .

Type: — VIETNAM. Lam Dong Province, “Annam”, Da Lat, 1954, Lambert 30 (photo, MNHN-P-P00403664!) .

Description: —Epiphyte or lithophyte. Pseudobulbs dark brown, warty, white pubescent, 3–4 cm tall. Leaf petiole white pubescent, 1–1.5 cm long; leaf blade narrowly ovate to narrowly elliptic, grassy green, 11.5–13 cm long, 2.5–3 cm wide, abaxial surface white pubescent. Peduncle white tomentose, 12–13 cm long, bearing normally 3–4 flowers opening simultaneously; floral bract widely lunate, densely white tomentose outside; pedicel and ovary densely brown tomentose, 15–16 mm long. Flowers widely opening, sepals and petals yellow with reddish brown tint near the base; lip yellow with reddish streaks. Sepal s broadly lanceolate, 19–23 mm long, 4–7 mm wide, apex blunt to obtuse, densely tomentose outside, glabrous inside. Petals glabrous, broadly lanceolate, slightly oblique, 18–19 mm long, 5–6 mm wide, blunt to almost round at apex. Lip recurved near the base; median lobe oblong, 8–10 mm long, 4–5 mm wide, rounded or truncate at apex, with small triangular mucro; side-lobes, 5–6 mm long, 2–2.5 mm wide, acute, erect and forward directed; the disc with 3 keels; lateral keels clavate, swelling distally, shorter but higher than median keel; median keel coming from the lip base to middle of median lobe and then forming median longitudinal inflation at the lip apex. Column finely hairy; anther cap with low longitudinal keel and small insignificant beak at front. Fruit not seen.

Habitat and phenology: —Trunk epiphyte and lithophyte in broad-leaved evergreen forest, at elevation of 1300– 1500 m a.s.l., particularly on granite and gneiss outcrops. Very rare. Flowers in May–June.

Distribution: — Vietnam (Lam Dong and Khanh Hoa provinces). Endemic.

Notes: —Among Campanulorchis species, only C. pulverulent a forms normally 2–4 flowers per inflorescence, while inflorescences in other species are always 1-flowered. Flowers of C. pulverulenta superficially resemble flowers of C. thao (which may be seen in LE 01089319, https://en.herbariumle.ru/?t=occ&id=72990), however, flowers of C. pulverulenta have median lobe of the lip 8–10 mm long, 4–5 mm wide (vs. ca. 10 mm long, 5 mm wide), side-lobes of the lip 5–6 mm long, 2–2.5 mm wide (vs. lip side-lobes ca. 1.2 mm long, 4 mm wide), and the median keel on the lip is long, prominent and lamellate (vs. median keel short and inconspicuous).

The yellow lip with reddish streaks of C. pulverulenta looks similar to those observed in C. globifera and C. longipes , whereas the flower lip of C. thao is uniformly ochre yellow.

The nomenclatural combination, Campanulorchis pulverulenta was proposed by Ponert (2017), based on Eria pulverulenta described in 1955 by Guillaumin. The single type specimen of E. pulverulenta was prepared in 1954 from cultivated plant collected by French botanist, Lambert in 1952 (collection number Lambert 30) near Dalat Town , the capital of Lam Dong Province of the southern Vietnam. This specimen now is stored in the Herbarium of the National Museum of Natural History in Paris (MNHN).

While other species of Campanulorchis in Vietnam are rather common, C. pulverulenta for a long time was known by the single type specimen. One additional collection was made many years later by L. Averyanov et al. in 1997 (LE 01069012, https://en.herbariumle.ru/?t=occ&id=40823) not far from Dalat Town on granite cliffs between Lam Dong and Khanh Hoa Provinces. No more collections of this extremely rare species were made till now. In 2022, several observations of C. pulverulenta were made in Lam Dong Province. Mr. Truong Quang Cuong found it as an epiphyte on mossy tree trunk in broad-leaved evergreen forest in Bidoup Mountains along Giang Ly River . Mr. Hoang Gia found this species in the same area along La Ba River . Two more wild collected living specimens of C. pulverulenta originated from Lam Dong Province were found in private orchid garden in Dalat Town (photo, LE 01123123, https:// en.herbariumle.ru/?t=occ&id=136416). Voucher herbarium specimens were prepared from these cultivated plants and stored at VNM herbarium. Presently it is clear that C. pulverulenta is very rare, strictly endemic species with specific habitat requirements connected with granite and gneiss outcrops and cliffs on the border of Lam Dong and Khanh Hoa provinces.

Species examined: — VIETNAM, Khanh Hoa Province, Khanh Son District, Lieng Ly River on E slope of Hon Giao Ridge at elevation 1300 m a.s.l., 24.04.199 7, L. Averyanov et al., VH 4302 (LE01069012 https://en.herbariumle. ru/?t=occ&id=40823) . VIETNAM, herbarium prepared from wild collected plants cultivated in Da Lat Town, originated from Lam Dong Province, Lac Duong District, Da Nhim Commune , 11 June 2022, Truong Ba Vuong, Ngo Quang Dang, BV 1522 (VNM, authentic photos LE01123123 https://en.herbariumle.ru/?t=occ&id=136416, LE01123477 https://en.herbariumle.ru/?t=occ&id=139781) . VIETNAM, herbarium prepared from wild collected plants cultivated in Da Lat Town, originated from Lam Dong Province, Lac Duong District, Long Lanh Commune , 11 June 2022, Truong Ba Vuong, Hoang Manh Dat, BV 1529 (VNM) .

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 2. Campanulorchis pulverulenta. A. Flowering plant. B. Portion of influence. C. Leaf apex, adaxial and abaxial side. D. Hairs on leaves on abaxial surface. E. Hairs on inflorescence peduncle. F. Floral bract, adaxial and abaxial side. G. Median sepal, adaxial and abaxial side. H. Lateral sepal, adaxial and abaxial side. I. Petal, adaxial and abaxial side. J. Lip adaxial, abaxial, and side view. K. Keels on adaxial basal part of the lip. L. Lip apex, adaxial surface. M. Column, ovary and pedicel. N. Column apex, side view. O. Stigma. P.Anther cap, views from different sides. Q. Pollinia.Photos by Truong Ba Vuong, photo correction and design by L.Averyanov, all photos are made from specimen Truong Ba Vuong BV 1522 https://en.herbariumle.ru/?t=occ&id=136416, https://en.herbariumle.ru/?t=occ&id=139781.