Taeniophyllum (section Loboglossum Schltr.) pyriforme Schuit., Juswara & Droissart, 2016

Juswara, Lina, Schuiteman, Andre & Droissart, Vincent, 2016, Four new orchid species from the Lengguru fold belt, West Papua, Indonesia, PhytoKeys 61, pp. 47-59 : 52-54

Taeniophyllum (section Loboglossum Schltr.) pyriforme Schuit., Juswara & Droissart sp. nov. Figs 2D , 4F-H

Diagnosis.

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.

Type.

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).

Description.

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.

Distribution and habitat.

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.

Etymology.

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

Notes.

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 Taeniophyllum 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.

Figures

Figure 1. Main localities sampled during Lengguru 2014 expedition and distribution of the four new species in West Papua, Indonesia.

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 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.