Similar to Bulbophyllum pyroglossum Schuit. & de Vogel because of the hinged lip and the hair-like appendages on the surface of the lip, but in that species the appendages are about four times longer, and they are discrete, subulate projections arranged in rows, not forming densely lacerate-fimbriate keels as in B. leucoglossum. Moreover, B. leucoglossum has two lamellae on the abaxial (concave) side of the lip; these are lacking in B. pyroglossum. The latter also has much broader and shorter petals, and an orange instead of a white lip.

Indonesia, West Papua Province, Kaimana Regency, Nusa Ulan village, Pegunungan Kumawa Nature Reserve, 04°0.3121'S, 133°5.1227'E, 15/11/2014, Droissart & Juswara 1789 (holotype: BO!, spirit material).

Epiphytic herb. Rhizome short, creeping; roots wiry, branching, 0.5 mm diam. Pseudobulbs closely spaced, light green, narrowly ovoid, 2.0–2.4 × 0.7–0.8 cm, with c. 10 longitudinal grooves, 1-leaved. Leaf deeper green, linear-elliptic, gradually narrowed towards the base, 8.8–10.3 × 1.3–1.4 cm, thin-coriaceous, apex acute. Inflorescences arising from the base of the pseudobulb, becoming fascicled, erect, 1-flowered. Peduncle wiry, erect-patent, 1-flowered, 7–9 cm long, glabrous, with two tubular, 4 mm long peduncle-scales. Floral bract tubular, strongly oblique, 4.5 mm long, apex acuminate. Pedicel-with-ovary terete, very slender, weakly 6-ribbed, almost straight or curved, c. 2.5 cm long, glabrous. Flowers opening widely, the sepals patent to reflexed; sepals and petals maroon; lip white, at base wine-red, basal part of the keels sulphur-yellow; column cream-colour tinged maroon, swollen basal part and foot light green; anther pale greenish. Dorsal sepal linear-oblong, 14.3 × 2.8 mm, 3-veined, apex acute. Lateral sepals free, obliquely linear-oblong, 13.4 × 3.3 mm, 3-veined, apex acute. Petals linear-oblong, slightly widened towards the base, glabrous, 2.6 × 0.8 mm, apex obtuse. Lip clawed, slightly mobile, attached to the column-foot by a 0.3 mm long, 0.4 mm wide ligament; claw in the basal half almost quadrangular, tapering towards the blade, 2.4 × 1.5 mm, glabrous, with erect, hemi-elliptic, lobe-like margins in the basal half; blade narrowly oblong, slightly tapering towards the apex, cucullate, strongly convex above, 9.7 × 2.3 mm, margins deflexed, finely lacerate-fimbriate; blade adaxially with one median keel and two lateral keels on each side, the keels finely lacerate-fimbriate; on the concave abaxial side with two lacerate-fimbriate lamellae; apex obtuse. Column 2.3 mm long, curved, strongly swollen at the base, with a short but distinct, thick, 1 mm long column-foot; apical column-wings each with two short obtuse teeth, the wings 0.4 mm wide; stigma in lateral view with protruding lower margin; anther helmet-shaped, 0.6 mm long, very slightly papillose; pollinia not seen.

Bulbophyllum leucoglossum is only known from the Lengguru fold belt in West Papua. It is currently recorded from a single location in the Kumawa Forest Reserve, near the village of Nusa Ulan (Fig. 1). The only population seen so far was found in submontane forest at 1005 m elevation, the plants growing epiphytically about 1.5 m from the ground on a slender, moss-grown, overhanging tree trunk in medium-sloping terrain. More than ten individuals were observed in the collecting locality, but only one was flowering at the time of our fieldwork (November).

From the Greek leuco-, white, and glossum, tongue, referring to the largely pure white lip.

A distinctive species because of the five laciniate-fimbriate keels on the lip, which give it a hairy appearance. The only other known species in the large section Codonosiphon with a distinctly hairy-looking lip is B. pyroglossum Schuit. & de Vogel from Papua New Guinea, which is similar in plant habit and in the size of the flower. See the diagnosis for the main differences between the two species.

The short and dense inflorescences with small, purple flowers and green-tipped, long-apiculate sepals resemble those of Dendrobium purpureum Roxb., a lowland species from Maluku and Sulawesi. However, the plant habit of the latter is completely different, as D. purpureum has robust, many-leaved, cane-like, tufted stems up to more than 50 cm long. Vegetatively, D. centrosepalum is more similar to D. aurantiroseum P.Royen ex T.M.Reeve from New Guinea, which also has unifoliate pseudobulbs on a creeping rhizome. However, the latter is a species from high elevations (2100–3350 m) with pink flowers that are about twice as large, while the sepals are not apiculate; in addition, the cross-ridge on the lip is situated below the middle in D. aurantiroseum and above the middle in D. centrosepalum.

Indonesia, West Papua Province, Kaimana Regency, Lobo village, Triton Bay, 03°43.7962'S, 134°3.5962'E, 28/10/2014, Droissart & Juswara 1736 (holotype: BO!, spirit material).

Epiphytic herb. Rhizome creeping, c. 3 cm long, growing downwards; roots 0.5 mm diam. Pseudobulbs closely spaced, erect, green tinged purplish, oblongoid-fusiform, 1.3–1.5 × 0.4 cm; main internodes 3; irregularly 5-ribbed; 1-leaved at apex, sometimes with a reduced additional leaf. Leaves glaucous green, deciduous, erect, narrowly elliptic, 3.3 × 1.1 cm; apex obtuse, minutely 3-dentate; margin smooth, slightly erose at apex; sheath very short. Inflorescence arising laterally from the upper internode of the leafless pseudobulb, erect, c. 12 mm long, c. 7-flowered; peduncle 5.2 mm long, covered by a few short scales in the basal part; rachis straight, 7 mm long. Floral bracts triangular, patent, 4.8 × 2.8 mm, apex acuminate, 3-nerved, glabrous. Pedicel-with-ovary narrowly clavate, c. 8.4 mm long, curved, with 5 rounded ribs, minutely papillose. Flower 10.5 mm long; sepals bright purple with greenish mucro; petals, lip and ovary bright purple. Sepals glabrous, but abaxially finely papillose on the slightly raised midvein; distinctly sharply apiculate at apex. Dorsal sepal ovate-oblong, 3.5 × 1.9 mm, 3-nerved; mucro 0.4 mm long. Lateral sepals obliquely narrowly ovate-oblong, much elongated in basal part, in total 10.8 × 2.8 mm, 4-nerved; mucro 0.9 mm long; mentum narrowly conical-cylindrical, 5.7 mm long, apex rounded, the closed apical part 4.8 mm long. Petals elliptic, 2.9 × 1.7 mm, emarginate, very shortly mucronate, 3-nerved, margin in upper half finely papillose. Lip when flattened subspathulate, 8.5 × 2.3 mm, at 5 mm above the base with a V-shaped transverse ridge, margins of the basal part adnate to the column-foot for 2.1 mm; apical part broadly elliptic, finely papillose along apical margin, apex rounded, minutely apiculate. Column rectangular, 1.9 mm long, wings truncate; foot 5.7 mm long; stigma semiorbicular, 0.8 mm wide, rostellum swollen, transversely oblongoid; anther cucullate-rectangular, 0.9 × 1.0 mm, minutely papillose, at base retuse, apex truncate and minutely erose; pollinia 0.7 mm long.

Figure 2. 

A Bulbophyllum leucoglossum: 1 flower 2 dorsal sepal 3 lateral sepal 4 petal; 5, lip, adaxial view 6 lip, abaxial view 7 detail of crest on lip 8 column and base of lip; all after Droissart & Juswara 1789; B Dendrobium centrosepalum: 1 flower 2 flower, lateral view 3 floral bract 4 dorsal sepal 5 lateral sepal 6 petal 7 lip 8 flower, cut open 9 column 10 anther 11 pollinia; all after Droissart & Juswara 1736; C Dendrobium taeniocaule: 1 flower 2 dorsal sepal 3 lateral sepal 4 petal 5 lip 6 mentum 7 column, lateral view 8 column, ventral view; all after Droissart & Juswara 1739; D Taeniophyllum pyriforme: 1 flower 2 dorsal sepal 3 lateral sepal 4 petal 5 lip 6 column 7 anther, dorsal view 8 anther, lateral view; all after Droissart & Juswara 1735. Single scale bar = 1 mm; double scale bar = 1 cm. Drawing: Judi Stone.

Figure 3. 

Photographs of living type specimens and habitats. Bulbophyllum leucoglossum: A habitat and habit B flower, side view C flower, front view D Flower close-up, showing details of the column and the labellum. Dendrobium centrosepalum: E habitat and habit F, G plant and inflorescence H inflorescence and flowers close-up. Photos: Vincent Droissart.

Dendrobium centrosepalum is only known from the Lengguru fold belt in West Papua. It is currently known from a single locality in the Triton Bay area, near the village of Lobo (Fig. 1). The only population seen so far was found in submontane forest at 1114 m elevation, the plants growing epiphytically on a thick, vertical, moss-and-lichen-covered trunk of a tree.

Figure 4. 

Photographs of living type specimens and habitats. Dendrobium taeniocaule: A habitat and habit B plant C flower and part of pseudobulb D flower, front view E flower, side view. Taeniophyllum pyriforme: F habitat and habit G plant and inflorescence H inflorescence and flowers close-up. Photos: Vincent Droissart.

From the Greek centron, a sharp point, referring to the apiculate sepals.

The small, bright purple flowers in short and dense inflorescences superficially resemble those of such species as D. dichaeoides Schltr. and D. limpidum Schuit. & de Vogel, but these are quite different vegetatively, having elongate, leafy stems; in addition, in these two species the sepals are not sharply apiculate. See the diagnosis for additional comparisons.

Similar to Dendrobium viridiflorum F.M.Bailey in the flattened stems and the sympodially branching inflorescences with 1-flowered branches. The new species differs from D. viridiflorum in the relatively much shorter mentum (3.6 mm versus 7 mm long, with the free part of the lip being of about equal length in the two species), the relatively much broader dorsal sepal, in the lip being wider than long (versus longer than wide), and especially in the much wider (8.5 versus 3.2 mm), bilobulate (versus entire) mid-lobe of the lip.

Indonesia, West Papua Province, Kaimana Regency, Lobo village, Triton Bay, 03°43.7962'S, 134°3.5962'E, 28/10/2014, Droissart & Juswara 1739 (holotype: BO!, spirit material).

Epiphytic herb. Rhizome short, creeping; roots 1 mm diam., minutely verrucose. Pseudobulbs erect, yellowish green, elongate, bilaterally flattened, 16–21 × 0.4–0.5 cm; internodes 2.3–2.6 cm long, each internode narrowed towards the base; leafy throughout, except for two or three basal internodes; 6–8-leaved. Leaves deep green, long-lived, patent, oblong, 2.0–3.3 × 0.6–0.9 cm; apex unequally bilobed; sheath much shorter than the internode. Inflorescence arising from the apex of the internodes in the upper part of the stem, sympodially branching with age, with up to 3 branches, each branch 3–8 mm long, 1-flowered; peduncle c. 6 mm long, covered with scales in the basal part. Floral bract triangular, closely appressed, 2.9 mm long, apex apiculate. Pedicel 2.6 mm long ovary at right angles to the pedicel, 2.6 mm long, glabrous; at the base of the pedicel with an abortive rachis. Flower 10.3 mm high, glabrous; sepals greenish white, tinged pale purple abaxially and on the mentum; petals pale green; lip white; column pale green suffused with purple; anther pale green. Dorsal sepal broadly ovate, 4.1 × 3.3 mm, 5-nerved, obtuse. Lateral sepals obliquely broadly ovate, the free part 5.3 × 4.3 mm, 5-nerved, obtuse; mentum cylindrical, 3.6 mm long, apex rounded, the closed apical part 2.8 mm long. Petals linear-oblong, 4.4 × 1.2 mm, acuminate, 3-nerved, margin in upper third finely papillose. Lip 3-lobed, clawed, when flattened 6.7 × 8.5 mm excluding the c. 4 mm long, linear claw; lateral lobes subfalcate-oblong, patent, 2.7 × 1.0 mm; mid-lobe clawed, bilobulate (the whole lip appearing 4-lobulate), 5.7 × 8.5 mm; mid-lobe claw obtrapeziform, 1.7 × 4.4. mm; lobules of the mid-lobe rectangular-orbicular, 3.3 × 4.2 mm; the whole of the lip, except for the lateral lobes and the lobules of the mid-lobe, occupied by a sharply delimited swelling, which has two broad longitudinal crests with a narrow rib in between and which projects backwards over the claw of the lip for 0.3 mm. Column broadly conical in front view, 1.7 mm long, wings very short, truncate; foot 3.6 mm long; stigma large, 1.6 mm wide, rostellum a simple transverse ridge; anther cucullate-rectangular, 1.1 mm wide, glabrous; pollinia not seen.

Dendrobium taeniocaule is only known from the Lengguru fold belt in West Papua. It is currently recorded from a single locality in the Triton Bay area, near the village of Lobo (Fig. 1). The only population seen so far was found in submontane forest at 1114 m elevation, the plants growing epiphytically on a vertical, lichen-covered trunk of a tree.

From the Greek taenia, a band or strap, and caulon, stem; referring to the flattened, band-shaped pseudobulbs.

This species has only one obvious close relative, which is the widespread D. viridiflorum. Uniquely in section Brevisaccata, these two species share flattened stems and abbreviated inflorescences that produce up to 3, 1-flowered branches in succession over a longer period. The other species in the section have terete stems and flowers produced simultaneously on elongate racemes. In addition to clear morphological differences, as indicated in the diagnosis, the two first-mentioned species also have different ecologies. While D. viridiflorum is exclusively found in mangroves and coastal forest below 200 m, D. taeniocaule occurs in submontane forest above 1000 m.

Differs from all known species in sect. Loboglossum by the finely muricate peduncle and the hook-like basal lobules of the lateral lobes of the lip.

Indonesia, West Papua Province, Kaimana Regency, Lobo village, Triton Bay, 03°43.7962'S, 134°3.5962'E, 28/10/2014, Droissart & Juswara 1735 (holotype: BO!, spirit material).

Leafless epiphytic herb. Stem very short; roots spreading, green, flattened, not branching, up to at least 35 cm long, 1.5–3 mm wide; some of the roots closely appressed to the bark of the phorophyte, others free hanging. Inflorescences c. 3 producing flowers at the same time, suberect, 5–6 cm long; peduncle filiform, 0.5 mm diam., rather sparsely muricate with c. 0.3 mm long projections; near the middle with a very small peduncle-scale; rachis distichous, glabrous, up to c. 16-flowered, with the flowers opening in succession, one or two at a time, gradually elongating, up to 11–14 mm long. Floral bracts cupular, in lateral view triangular, subacute, 1.2 mm long; successive bracts on the same side of the rachis 1.8 mm apart. Flowers apparently non-resupinate (always?), c. 5 mm high including the spur, glabrous, pale brownish yellow. Dorsal sepal ovate, 3.3 × 1.5 mm, obtuse, 3-veined. Lateral sepals somewhat obliquely ovate, 2.6 × 1.3 mm, obtuse; 3-veined; abaxially at the apex with a short lamella along the midvein. Petals obliquely ovate, 3.2 × 1.5 mm, obtuse, 3-veined. Lip spurred, 3-lobed, ecallose, margins erect to incurved, when flattened 2.7 × 3.2 mm; lateral lobes semi-oblong, rounded, 2.0 mm long from base of lip to base of mid-lobe, at the base with an erect, narrowly triangular-uncinate lobule; mid-lobe reniform, 0.7 × 1.2 mm, emarginate. Column short, cylindrical, 1.1 long, 1.0 mm wide, with a short, bidentate rostellum; stigma shallowly concave; anther cucullate, 0.9 cm long, 0.6 cm wide, apex rostrate, recurved; pollinia not seen.

Taeniophyllum pyriforme is only known from Papua. It is recorded from a single locality near the village of Lobo in the Triton Bay (Fig. 1). The only population seen so far was found in submontane forest at 1114 m elevation, the plants growing epiphytically on a sparsely moss-covered tree trunk at 1.5 m above the ground.

From the Latin pyriforme, pear-shaped, referring to the shape of the spur.

This inconspicuous but distinctive species would seem to fit best in section Loboglossum, on account of the clearly lobed lip, elongate inflorescence, distichous rachis, and glabrous ovary. However, a muricate inflorescence has not been reported for this section before (although the otherwise very different Taeniophyllum toranum J.J.Sm. is described as having a furfuraceous-punctate peduncle and rachis, while the no less distinct T. pulvinatum is said to have a minutely glandulose peduncle). The basal, hook-like lobules on the lip are also unique.

It is likely that a large number of species of Taeniophyllum still await discovery in New Guinea. We believe this to be the case because most of the species are easily overlooked; the flowers often last only a day or less; and many of the known species are only recorded from the type. New Guinea is clearly the centre of diversity for this genus, with 130 species currently recorded.