Agrostophyllum superpositum

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., Repert. Spec. Nov. Regni Veg. Beih. 1 (1912) 278

Type: Schlechter 19534 (holo B, lost; iso AMES, BO, K)

Synonyms:

  • Agrostophyllum curvum Ridl., Trans. Linn. Soc. London, Bot. 9 (1916) 199
    - Type: Kloss s.n. (Camp 6b, 3900 ft.) (syn K); (Camp 6c, 5500 ft.) (syn BM)
  • Agrostophyllum congestum Schltr., Bot. Jahrb. Syst. 58 (1922) 77
    - Type: Ledermann 10317 (holo B, lost)

Plant to c. 135 cm long, pendulous or straggling. Rhizome rather to strongly elongated, 0.4-0.8 cm diam. Bract-like scales close together, overlapping, distichous, narrowly triangular, to 5.9 by 0.7 cm, without or with a small tubular basal part. Stems up to 50 per rhizome, rather wide to wide apart, appressed to or with a sharp angle to the rhizome, to 9 cm long, 0.6-1.8 cm wide over the leaf sheaths, flattened, from base to top gradually widening, with 2-7 leaves and one terminal capitulum. Leaf sheaths rather loose around the stem, hardly overlapping each-other, with a 0.8-3.6 cm long incision, without or with a tubular basal part, the lowest one reaching to or beyond the base of the highest one, 0.8-3.6 cm long, width of margin to midrib 0.3-0.7 cm; margin dark-coloured; top margin at the articulation without projection or drawn out into a slender, 0.1-1.1 cm long, tooth-like projection. Leaf blade in an acute angle to the stem, linear-lanceolate to linear, 2.7-16.0 by 0.4-0.9 cm, index 4.8-20; base sometimes twisted and then upper side of the leaf blades turned to one side of the stem; top acute to very slender acute; its tip mostly acute, often with a tiny mucro, sometimes equally or unequally bilobed or bidentate; many-nerved. Inflorescence a dense, more-flowered capitulum terminal on a stem, 1-30 (- 40) per plant, 0.9-3.0 by 0.4-1.5 cm. Bracts first order at anthesis persistent, to 3.6 cm long. Partial inflorescences 1 to many per capitula, with 4(-5) bracts second order of which the lowest 3(-4) are sterile; axis 0.1-0.3 cm long. Bracts second order transparent, tubular to c. halfway, at anthesis persistent, soon weathering, lower ones smaller than upper ones, the fertile one completely covering pedicel and ovary, 0.65-1.3 cm long; top acute; nerves many, fine, inconspicuous. Pedicel and ovary straight, not twisted, strongly ribbed, 0.5-0.9 cm long. Flowers not resupinate, hidden between the fibres of the bracts second order, widely open, (0.3-)0.60-0.90 cm diam.; mentum pronounced, obtuse, 0.1-0.26 cm long. Median sepal broadly attached, concave, ovate, sometimes recurved,0.5-0.7 by 0.28-0.4 cm, index 1.5-2.1; top acute to slightly acuminate; nerves 5-6, midrib a low rounded keel, pronounced to the top, the nerves next to the midrib often thickened towards the top. Lateral sepals broadly attached, mostly connate at the base, sometimes clasped in a groove in the saccate base of the hypochile, concave, ovate, sometimes recurved, 0.60-1.05 by 0.28-0.45 cm, index 2.1-3.0; top acute to acuminate; nerves 3-7, midrib a low rounded keel, pronounced to the top. Petals narrowly attached, ovate-ligulate, 0.4-0.67 by 0.15-0.21(-0.24) cm, index 2.5-4.0; top acute with obtuse to acuminate tip; margin irregular; nerves 3-5. Lip sessile, immobile, 0.67-1.03 cm long, at the backside from the base of the hypochile to c. middle of epichile with one or more longitudinal grooves. Hypochile 0.2-0.4 by 0.12-0.2 by 0.1-0.25 cm, inside with 3 swollen, longitudinal ribs; base more or less deeply saccate; lateral lobes low, in front broadly rounded; on junction with the Epichile with a transverse, plate-like, rather high callus which overtops the lateral lobes, its top margin truncate with 2-3(-4) more or less distinct teeth. Epichile broadly sessile, concave, ovate to orbicular, 0.47-0.77 by 0.4-0.65 cm, index 0.8-1.4; margin curved upwards, slightly indented or almost entire, undulate; base median just below the callus with 2-3, rarely more, often irregular longitudinal calli; top (broadly) rounded or acuminate, rarely saccate, with an apiculum or a thickened, irregular winding ridge at the backside of the epichile near the top; sometimes with longitudinal grooves towards the top. Column club-shaped, widened around the stigma, excluding column-foot and anther 0.25-0.4 by 0.15-0.23 cm; often just below the stigma at the depression with an elevated band of tissue; laterally on either side with a ridge which is next to the stigma drawn out into a not distinct, broadly rounded to triangular, wing-like lobe; sometimes on the junction with the column-foot with 2 ovoid calli; column-foot short, median with a broad, shallow to rather deep, longitudinal groove, 0.1-0.15 by 0.07-0.1 cm; clinandrium terminal with low erect margins clasping the anther which in front continue in the rostellum. Anther 2-locular, about globose to broadly ovoid, c. 0.17-0.2 by c. 0.2 cm. Pollinia 8, on a common caudicle, obovoid, 0.1-0.16 by 0.04-0.07 cm, often unequal in size. Stigma in outline quadrangular to rectangular, 0.1-0.24 by 0.1-0.18 cm; rostellum folded to the front, median deeply notched and there parted in two, or median notched and apiculate. Fruit a fusiform capsule with perianth and/or column on top persistent; body 0.4-1.3 by 0.15-0.4 cm; 3 valves with a low rounded keel. Seeds not seen. (After Weijnen and De Vogel, unpublished).

Note: Easily recognised by the pendulous, stem-like rhizomes.


Leaves dull to dark (olive) green. Floral bracts brown. Flowers cream colour to pure white, sometimes on the base of the mid-lobe of the lip with a yellow to orange-yellow spot. Anther pale to dark brown with paler margins.Colours

Epiphyte in montane forest in shaded positions. Altitude 1000-2930 m.

Malesia (New Guinea), Solomon Islands.

Papua (Indonesia); Papua New Guinea. See map

distribution in New Guinea

Intermediate growing epiphyte, keep in shade.

April, May, June, July, December.

  • Family Orchidaceae
  • Subfamily Epidendroideae
  • Tribe Undetermined
  • Subtribe Agrostophyllinae
  • Genus Agrostophyllum
  • Section Oliganthe
  • Species Agrostophyllum superpositum
  • Smith, J.J., Nova Guinea 12, 3 (1915) 235, t. 81, fig. 139
  • Schlechter, R., Repert. Spec. Nov. Regni Veg. Beih. 21 (1923) t. 103, fig. 383
  • Lewis, B.A. & P.J. Cribb, Orchids of the Solomon Islands and Bougainville (1991) 130
  • O'Byrne, P., Lowland Orchid. Papua New Guinea (1994) 122, fig.

Sponsored Ads

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Flowering branch. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Plant habit. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Flower, front view. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Flower, oblique front view. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Flower, front view. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Flower, oblique lateral view. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr. Flower, lateral view. Photo by Ed de Vogel, based on Leiden cult. 20030347 (de Vogel & Vogel)

Agrostophyllum superpositum

overview picture

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., drawing J.J. Smith, from Janowsky 362

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., drawing J.J. Smith

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., drawing J.J. Smith

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., from Repert. Spec. Nov. Regni Veg. Beih. 21 (1923) t. 103, fig. 383

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., as Agrostophyllum curvum, Ridl., drawing by Paul Ormerod, Checkl. Papuasian Orch. (2017) 11, 459 (fig.).

Agrostophyllum superpositum

Agrostophyllum curvum Ridl., syntype specimen (BM), mounted upside down

Agrostophyllum superpositum

Agrostophyllum superpositum Schltr., herbarium sheet, Schlechter 19534, isotype specimen (BO), mounted upside down