Bonatea cassidea Sond., Linnaea 19: 81 (1846).
Heterotypic Synonyms:
Habenaria cassidea Rchb.f. in W.G.Walpers, Ann. Bot. Syst. 1: 797 (1849).
Habenaria saundersiae Harv., Thes. Cap. 2: 29 (1863).
Bonatea darwinii Weale, J. Linn. Soc., Bot. 10: 470 (1869).
Bonatea saundersiae (Harv.) T.Durand & Schinz, Consp. Fl. Afric. 5: 89 (1894).
Erect, decumbent or scandent terrestrial herbs, 100-640 mm tall; tubers 1-8, spreading, elongate-oblong, tomentose. Stem slender, 95-630 x 1.5-5.0 mm. Leaves sometimes withered at flowering, 5-13, lax, cauline, lower leaves intermediately basal, sheathing, narrowly- obovate to oblanceolate, acute to acuminate, margins entire, rarely undulate, 20-250 x 4-19 mm. Inflorescence cylindrical, 40-212 x 3464(- 80) mm, lax to dense, 3-35-flowered; bracts sometimes withered at flowering, similar to upper leaves, sheathing, linear-oblong to ovatelanceolate, apiculate, 10-25 x 2.5-7.5 mm. Flowers spreading, green and white, pedicel and ovary sub-erect to erect, 14-32 mm long. Dorsal sepal green, sub-erect to erect, elliptical-oblong, galeate, acute to acuminate, 7.0-13.5 x 3-5 mm; lateral sepals green, patent, strongly deflexed, oblong-lanceolate to ovate, acute to apiculate, base oblique, margins weakly to strongly revolute with small acute tooth on lower margin, 7.0-15.5 x 2.0-6.5 mm, adnate to lip and stigmatic processes for 3-6 mm. Petals upper lobe green or white, erect, linear, acute to acuminate, 6-14 x 0.5-2.0 mm, adnate to dorsal sepal, lower lobe white, spreading horizontally, weakly to strongly deflexed, falcate, lanceolate to widely-obovate, tip curved, acute to apiculate, 8.5-15.0(19.0) x (1.5-)3.0-8.0 mm, adnate to claw of lip for 1-5 mm. Lip claw 3-9 mm, median lobe green or white, descending, weakly to strongly geniculate, filiform to linear, acute, 5.5-17.0 x 0.5-2.0 mm, lateral lobes white, descending, diverging, falcate, narrowly to broadlyoblanceolate, tips curved, apiculate, 6.5-21.0 x 1.5-6.5 mm; spur toothed, curved, 12-26 mm long, clavate apex 8-17 mm long. Anther erect, acute, 2.5-5.5 mm long, canals slender, 3.5-5.5(-9.5) mm long. Stigmatic processes clavate, projecting forwards and deflexed, weakly divergent, 3.5-7.0(-10.5) mm long, base adnate to lip. Rostellum 3 lobed, base auriculate, median lobe narrowly-cucullate, apiculate, margin ciliate, 3.0-5.5 mm long, lateral lobes linear, fused to anther canals, sub-erect to 45°, sub-parallel, 0.5-2.0(-6.5) mm long. Flowering period: July to September.
Acacia savannah, forest and thicket, from 60 m to 1500 m altitude. Bonatea cassidea occurs consistently in open shady niches often in close proximity to water.
E. Zimbabwe to S. Africa
La Croix, I. & Cribb, P.J. (1995). Orchidaceae (Part 1) Flora Zambesiaca; Linder, H.P. & Kurzweil, H. (1999). Orchids of Southern Africa A.A. Balkema, Rotterdam; Ball, J.S. (2009). Terrestrial African Orchids; Wild Orchids of Southern Africa Stewart, Linder, Schelpe & Hall 1982; The Wild Orchids of Southern Africa Stewart, Schelpe, Linder and Hall 1982
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Habitat/In situ
Bonatea cassidea,  01
Photograph© Cameron
McMaster. Image used
with kind permission.