Bulbophyllum biserratum

Bulbophyllum biserratum J.J.Verm., Nordic J. Bot. 26 (2008) 135, fig. 4

Type: Leiden cult. 20030162 (holo L), from PNG, Woitape

Roots sprouting near the base of the rhizome, growing backwards along it until reaching the substrate. Rhizome c. 1.5 mm in diameter, sections between pseudobulbs 0.4-0.6 cm long, erect to patent, bracts not persistent. Pseudobulbs 0.8-0.9 by0.25-0.35 cm, loosely clustered, ovoid. Leaves: petiole 0.1-0.4 cm long; blade 1.7-4.5 by 0.45-0.5 cm, index (length/width) 3.4-10, elliptic, apiculate. Inflorescence c. 1 cm long, 1-flowered; peduncle c. 0.15 cm long, porrect; non-floriferous bract 1, c. 2.5 mm long; floral bract c. 3.5 mm long, tubular, apiculate. Flowers widely opening. Pedicel-with-ovary c. 5 mm long, basal node on a c. 0.3 mm long stump. Dorsal sepal c. 4.8 by 2.2 mm, index c. 2.2, spreading, elliptic-ovate, subacute, margins slightly erose distally, base rather broadly attached, thin, surface glabrous. Lateral sepals c. 5 by 2 mm, index c. 2.5, free, ovate, lower margin sharply folded inwards, slightly erose, otherwise as the dorsal sepal. Petals c. 1.7 by 0.4 mm, index 4.2-4.3porrect, oblong, rounded, margins finely erose, base rather narrowly attached, thin, surface glabrous. Lip c. 3.5 by 0.7 mm, index c. 5, attached to the column-foot by a narrow, transverse area and still partly mobile, gently sigmoid, oblong-spathulate, rounded, margins entire, with a row of flattened, more or less triangular appendages in the middle third, thick and spongy, surface glabrous; adaxially without a transverse ridge and concave just above the area of attachment, with two low, obtuse keels starting near the base, at the margins, then quickly converging until they almost meet, then continuing parallel and close together, leaving a narrow furrow in between, up to about one third of the length of the lip, surface otherwise convex; abaxially convex, with a shallow median furrow proximally. Column c. 1.2 mm long, more or less straight; stigma elliptic, without keels inside; foot not widened distally, with a transverse, flat, slightly antrorse ledge just above the area of attachment; stelidia c. 0.3 mm long, triangular, acute, with a deltoid, rounded to obtuse wing along the lower margin; anther-cap abaxially with a slight, papillose crest, surface otherwise more or less glabrous, front margin not drawn out; pollinia 4, obovoid, all flat, the inner as long as the outer; no appendages. (After Vermeulen, 2008)

Colours: Sepals creamy-white with red nerves, petals creamy-white, lip proximally dull purple, the swollen distal part pale dull yellow.

Flowering time in the wild: December.

Distribution: Malesia (New Guinea).

Distribution in New Guinea: Papua New Guinea; Papua New Guinea; see map 96-2270M.jpg.