Bulbophyllum dasystachys J.J.Verm., Thavipoke & Phelps, 2014

Vermeulen, Jaap J., Phelps, Jacob & Thavipoke, Patana, 2014, Notes on Bulbophyllum (Dendrobiinae; Epidendroideae; Orchidaceae): two new species and the dilemmas of species discovery via illegal trade, Phytotaxa 184 (1), pp. 12-22 : 14-18

Bulbophyllum dasystachys J.J.Verm., Thavipoke & Phelps , sp. nov. ( Figs. 4–7 )

Type:— Origin unknown, Vermeulen 3144, cult. Christiansen (holotype L!, isotype BKF!) .

Diagnosis: Most similar to B. lindleyanum Griffith (1851: 287 ; section Hirtula). This species differs by having larger flowers (median sepal 5.1–6.5 mm long), as well as a lip that is glabrous adaxially.

Creeping epiphyte with spreading roots. Rhizome 4–7 mm diam., sections between pseudobulbs 1.0– 3.5 cm long. Pseudobulbs ovoid to depressed-conical, 1.3–2.8 × 1.5– 2.6 cm. Leaf with petiole 1.8–3.0 cm long, blade elliptic, 14.0–15.0 × 2.3–2.8 cm, ratio length/width 5.3–6.1, acute. Inflorescence an erect to patent, elongate, dense raceme with the flowers spirally arranged, c. 34 cm long, c. 42-flowered. Peduncle c. 24 cm long, scales c. 5. Rachis green or blackish purple, with white or blackish purple papillae, approximately as thick as peduncle, slightly nodding at the base, c. 10 cm long, coarsely papillose with patent, elongate papillae; floral bracts 5–6 mm long. Flowers only opening a few simultaneously. Pedicel plus ovary 5–6 mm long, particularly towards the apex coarsely papillose with patent, elongate papillae, basal node c. 0.5 mm above the floral bract attachment. Sepals and petals pale green towards the base, yellowgreen to blackish-purple towards the apex, with green or blackish-purple veins; papillae white to blackish-purple, long hairs yellow; median sepal free, recurved to spreading, apex reflexed, ovate, c. 3.3 × 2.6 mm, ratio length/width 1.2–1.3, acute, margins entire, papillose, towards the base with elongate papillae, as well as long-ciliate, adaxially hirsute with short hairs as well as pilose with scattered long hairs, abaxially coarsely papillose with patent, elongated papillae, triveined; lateral sepals as the median but ovate-triangular, c. 3.5 × 3.5 mm, ratio length/width c. 1, acute-acuminate, upper margin not long-ciliate. Petals porrect, triangular with a slightly widened base, c. 1.4 x 0.8 mm, ratio length/ width 1.7–1.8, subacute, margins entire, minutely papillose and ciliate towards the apex, adaxially minutely papillose towards the apex, abaxially glabrous, 1-veined. Lip pale green, yellow-green or pale red towards the apex, apical callus green, abruptly recurved half-way along its length, distinctly auriculate near the ligament, (ovate-)oblong, c. 2.1 × 1.5 mm, ratio length/width c. 1.4 (without spreading), rounded, margins entire, short-ciliolate as well as long-ciliate, less distinctly so near the apex, adaxially concave and with a short median ridge in a deep furrow near the base, this ridge in front enclosed by the sides of the furrow that converge and touch to form a median slit that continues until it abruptly opens widely again near the apex of the lip to allow space for a somewhat raised median callus, adaxial surface densely and finely hirsute except for the apical callus and the area near the base, this indument grading into coarser and longer hairs towards the margins, abaxially with a short, wide ridge near the base, convex towards the apex, surface glabrous but finely hirsute towards the apex. Column including stelidia c. 2.3 mm long, column foot somewhat swollen distally. Stelidia slightly downwards falcate, subulate with a slightly swollen, minutely papillose apex, c. 1.2 mm long, obtuse, upper margin with a minute, deltoid, acute tooth near the base, lower margin with a distinct, deltoid, rounded wing near the base. Anther with connective in front papillose-ciliate, abaxial ridge papillose.

Distribution:— Thailand, Prachinburi Prov., Khao Yai National Park, Tripetch s.n.(a photographic record), 25/11/2007.

Ecology:— Tripetch s.n. was found close to the forest floor on a tree bordering a stream, near a waterfall, at c. 700 m asl.

Etymology:— Dasys (Greek) = rough, stachys (Greek) = raceme.

Conservation status:— Unknown. Recorded from within a national park, albeit one that is a known source of wild plants for trade.

Figures

FIGURE 4. Bulbophyllum dasystachys. A. Plant. B. Flower. C. Flower analysis, from left to right: median sepal, petal, lateral sepal, lip. D. Lip, above: adaxial side, below: abaxial side. E. Column and lip, lateral view. F. Anther, left: adaxial side, right: abaxial side. G. Pollinia, above: single pair, below: two pairs (origin unknown, Vermeulen 3144, cult. Christiansen). Illustration: J.J. Vermeulen

FIGURE 5. Bulbophyllum dasystachys (Vermeulen 3144, cult. Christiansen). Photo: J.J. Vermeulen

FIGURE 6. Bulbophyllum dasystachys (Thailand, Khaoyai National Park, Tripetch s.n., 25/11/2007). Photo: P. Tripetch

FIGURE 7. Bulbophyllum dasystachys, in situ (Thailand, Khaoyai National Park, Tripetch s.n., 25/11/2007). Photo: P. Tripetch