AFRICAN

ORCHIDS

Bulbophyllum intertextum Lindl., J. Proc. Linn. Soc., Bot. 6: 127 (1862).
Homotypic Synonyms:
Phyllorkis intertexta (Lindl.) Kuntze, Revis. Gen. Pl. 2: 677 (1891).
Heterotypic Synonyms:
Bulbophyllum seychellarum Rchb.f., Linnaea 41: 93 (1876).
Bulbophyllum quintasii Rolfe, Bol. Soc. Brot. 9: 138 (1891).
Phyllorkis seychellarum (Rchb.f.) Kuntze, Revis. Gen. Pl. 2: 678 (1891).
Bulbophyllum viride Rolfe, Bull. Misc. Inform. Kew 1893: 170 (1893).
Bulbophyllum usambarae Kraenzl., Bot. Jahrb. Syst. 34: 58 (1904).
Bulbophyllum triaristellum Kraenzl. & Schltr., Orchis 2: 98 (1908).
Bulbophyllum amauryae Rendle, Cat. Pl. Oban: 101 (1913).
Bulbophyllum pertenue Kraenzl., Bot. Jahrb. Syst. 51: 385 (1914).
Bulbophyllum intertextum var. parvilabium G.Will., Pl. Syst. Evol. 134: 62 (1980).
Description:
Roots 0.3-0.6 mm diam. Rhizome 0.7-1.2 mm diam., nodes not or hardly swollen. Rhizome scales tubular, tip acute or subacute; membranous, with some nerves; not keeled abaxially. Pseudobulbs 1-leafed, ovoid to about orbicular, 0.2-2.5 (- 4) cm apart, 0.4-1 by 0.3-0.7 cm, either flattened or not, obtusely 4 (- 5)-angled. Petiole 0.2-2 mm long. Leaf blade elliptic to linear-lanceolate, 0.7-10 by 0.3-1.1 cm, tip rounded to acute, either emarginate or not, not oblique; coriaceous, thick; midrib hardly prominent abaxially. Inflorescence 2-30 cm long, 2—14(— 20)-flowered. Peduncle erect to patent, usually wiry, 1.8-11 cm by 0.3-0.6 mm, orbicular in section, glabrous, with 3-5 scales. Peduncle scales tubular, the longest 3-5 mm long; tip acute; membranous, without nerves; not keeled and glabrous abaxially. Rhachis arching or nodding, terete, usually zigzag bent, 0.2-19 cm long, glabrous. Floral bracts recurved, elliptic to oblong, 1.5—3 (- 4) by 1-2 mm, tip acuminate; base rather broadly attached; membranous, without nerves; not keeled and glabrous abaxially. Flowers distichous, in a lax raceme, recurved, many open simultaneously, not fully open. Pedicel and ovary 1-2 mm long, glabrous. Median sepal not or hardly recurved, ovate-oblong to ovate-lanceolate, 3-6 by 0.9-2 mm, tip cuspidate; margins entire, glabrous to finely papillose; base broadly attached; thin; locally very finely papillose adaxially; not keeled abaxially. Lateral sepals free, slightly recurved, hardly falcate, (very narrowly) triangular, oblique, 2.8-6 by 0.8-3 mm, otherwise as the median sepal. Petals not or hardly recurved, hardly falcate, broadly elliptic to oblong, oblique, 1-3 by 0.5-1.6 mm, tip rounded to acute; margins slightly irregular towards the tip, glabrous; base rather broadly to rather narrowly attached; very thin; glabrous or with a few coarse papillae; not keeled abaxially. Lip recurved, triangular, ovate or elliptic in outline (not spread), 1.2-4 by 0.7-2 mm, tip rounded to subacute; margins entire, with short or long hairs, or about glabrous, top part glabrous to finely puberulous; thick; adaxially with a more or less thickened median part, with a slightly concave basal part, with a median slit starting at about the base and continuing over 1/2-2/3 of the lip, surface glabrous, papillose towards the margins; abaxially with a weak rounded ridge in the basal half, surface glabrous, locally slightly papillose. Column from the base of the free part up to the tip of the stelidia 0.8-2.2 mm long, with distinct, (very narrowly) triangular, not or hardly falcate, rounded to acuminate or about truncate stelidia of 0.3-1 mm long; column occasionally with either folded inwards or not, weak to distinct, deltoid, rounded to subacute wings or teeth along its adaxial margins just below the base of the stelidia; stigma with or without a weak to distinct, obtuse basal tooth or callus. Anther c. 0.5 by 0.6 mm; front not drawn out; front margin rounded, entire, papillose; basally distinctly emarginate; abaxially with a very weak, rounded, colliculate ridge near the top of the anther which hardly overtops the front margin, surface colliculate. Pollinia 2; ellipsoid or obovoid, flattened on one side; a stipes has not been observed. Fruit obovoid to ellipsoid, up to 0.6 by 0.4 cm, stalk 1 mm.
Colours:
Pseudobulbs often stained with red. Leaves green. Flowers very pale yellowish or greenish, often partly suffused with purpie or purple-red, or entirely purpie or purple-red.
Habitat:
Lowland forest, montane forest, also recorded from ‘semi-montane grasslands’ (Sanford, 1974). Epiphytic in the crown of trees, on bark, minor humus deposits or moss cushions (Johansson, 1974; La Croix, written comm.). Rare in Brachystegia woodland (La Croix, written comm.). Occasionally lithophytic.
Notes:
Bulbophyllum intertextum is very variable in all its parts. In spite of this it is impossible to distinguish varieties because all extremes are linked by series of intermediates.
The variability in the vegetative parts may partly be due to differences in habitat: as far as can be concluded from herbarium labels humid forest specimens tend to be much more elongate in the vegetative parts than specimens from drier environments.
The lip especially is variable in general outline, and the length as well as the number of the ciliae along the margins.
The ciliae along the lip may be long, short or even almost absent. The latter character occurs in the specimens Louis, Breteler & De Bruin 1242 from GAB. and, according to the description, in the holotype specimen of var. parvilabium from ZAM. (not studied, an isotype specimen in K certainly has a ciliate lip). Other characters ascribed to var. parvilabium do not hold because of the existence of series of intermediate specimens. Therefore var. parvilabium can not be maintained as a separate variety.
The column is also variable. The projections next to the stelidia, described above, may either be present or absent. Besides, in some specimens (e.g. Le Testu 5707 from GAB.) the column is much more elongated than in others (e.g. Linder 334a from LIB.). Here, too, series of intermediates exist.
All the characters mentioned in the notes are distributed in a reticulate pattern over the material observed. Only two characters occur more or less together: specimens with wide leaves tend to have an elliptic to ovate lip, not a triangular one.
2 - The specimen Le Testu 5720 (from GAB.) may well be a natural hybrid with B. pumilum. It is intermediate between the two species.
Cultivation:
These plants adapt easily to intermediate to warm temperatures and either mounting or potting as long as there is light shade and adequate moisture.
Distribution:
Trop. Africa, Madagascar, Seychelles
References:
Orchids of East Africa Piers 1968; The Orchids of South Central Africa Williamson 1977; Orchids of Malawi La Croix 1983; Flora of Tropical East Africa Orchidaceae Part 2 Cribb 1984; Orchid Monographs Vol 2 - A Taxonomic Revision of the Continental African Bulbophyllinae Vermeullen 1987; Flora Zambesiaca Vol 11 Part 1 Pope 1995; Orchids of Kenya Stewart 1996; African Orchids in the Wild and Cultivation La Croix 1997; Bulbophyllum and Their Allies Siegerist 2001; Field Guide to the Ethiopian Orchids Demissew, Cribb & Rasmussen 2004; Orchidaceae Of West Central Africa Vol 2 Szlachetko, Ejsmont, Baranow, Grochocka, Nowak, Margonska and Naczk 2015
Images:
Click on each image to see a larger version.

Habitat/In situ  Habitat/In situ  Habitat/In situ 
bulbophyllum intertextum 01  bulbophyllum intertextum 02  bulbophyllum intertextum 03 
Photograph©Bart
Wursten. Image used
with kind permission. 
Photograph©Bart
Wursten. Image used
with kind permission. 
Photograph©Bart
Wursten. Image used
with kind permission.