AFRICAN

ORCHIDS

A key to the species of Bonatea

1 Leaves in a basal rosette 2
1b Leaves cauline, not in a basal rosette 3
2 Spur 20-47 mm long Bonatea polypodantha
2b Spur 53-70 mm long Bonatea pulchella
3 Spur >74 mm 4
3b Spur <69 mm 5
4 Lip lateral lobes 35-60 mm long Bonatea steudneri
4b Lip lateral lobes 106-135 mm long Bonatea lamprophylla
5 Leaves withered at flowering time 6
5b Leaves not withered at flowering time 7
6 Lip median lobe straight; rostellum elongate-rostrate Bonatea stereophylla
6b Lip median lobe geniculate; rostellum cucullate Bonatea porrecta
7 Tooth lacking in spur mouth Bonatea rabaiensis
7b Tooth present in spur mouth 8
8 Rostellum lateral lobes longer than median lobe Bonatea volkensiana
8b Rostellum lateral lobes shorter than median lobe 9
9 Leaves linear-lanceolate; rostellum median lobe narrowly cucullate; bracts dry at anthesis 10
9b Leaves ovate, oblong or broadly lanceolate; rostellum median lobe cucullate; bracts green at anthesis 11
10 Lower petal lobes ( 13-) 16-24x0.5-2.0(-3.0) mm; lip lateral lobes 0.5-2.0 mm wide Bonatea saundersioides
10b Lower petal lobes 8-15(-19)x(1.5-)3.0-8.0 mm; lip lateral lobes (1.5)2.0-6.5 mm wide Bonatea cassidea
11 Clavate apex of spur > 15 mm long; lower petal lobe >2 mm wide; lower petal lobes projecting forwards and deflexed Bonatea speciosa
11b Clavate apex of spur < 15 mm long; lower petal lobe <2 mm wide 12
12 Lower petal lobe (18-)24-43 x 0.5-2.0 mm, projecting forwards and ascending; stigmatic processes (11 —) 15—22 mm long Bonatea antennifera
12b Lower petal lobes 11 24(—28) x 0.5-2.0(-2.5) mm, spreading horizontally; stigmatic processes 8-15 mm long Bonatea boltonii

World Checklist of Selected Plant Families. The Board of Trustees of the Royal Botanic Gardens, Kew. Published on the Internet; http://www.kew.org/wcsp/ 12/12/2013

Bonatea volkensiana (Kraenzl.) Rolfe in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 253 (1898).
Homotypic Synonyms:
Habenaria volkensiana Kraenzl., Bot. Jahrb. Syst. 19: 244 (1894).
Description:
Erect, decumbent or scandent terrestrial herbs, 210-660 mm tall; tubers 2-10, spreading, elongate-oblong, tomentose. Stem slender to robust, 205-650 x 2.5-10.5 mm. Leaves 7-15, lax to dense, cauline, lower sheathing, blades reduced, lanceolate to oblanceolate, acute to acuminate, margins entire, smooth to undulate, 27-123 x 10-41 mm. Inflorescence cylindrical, 89-221 x 55-123 mm, lax to dense, 6-27flowered; bracts similar to upper leaves, sheathing, lanceolate to ovatelanceolate, apiculate, 16-35 x 5-12 mm. Flowers spreading, green and white, pedicel and ovary sub-erect to erect, 25-43 mm long. Dorsal sepal green, erect, elliptical-lanceolate, galeate, acute to acuminate, 13.0-18.5 x 4-8 mm; lateral sepals green, patent, strongly deflexed, widely oblong-ovate, acute to apiculate, base oblique, margins weakly revolute with acute tooth on lower margin, 11.5-17.5 x 5.5-9.5 mm, adnate to lip and stigmatic processes for 4.5-8.0 mm. Petals upper lobe green, erect, linear, acute to acuminate, 12.5-19.5 x 0.5-2.0 mm, adnate to dorsal sepal, lower lobe white with green tip, projecting forwards, ascending, weakly divergent, linear-falcate, tip curved, acuminate, (21-)25-38.5 x 0.5-1.5 mm, adnate to claw of lip for 3-6 mm. Lip claw 10.0-14.5 mm, median lobe green, descending, geniculate, sometimes apically recurved, linear-lanceolate to narrowlyoblong, acute to acuminate, 11.5-25.0 x 1.0-2.5 mm, lateral lobes white with green tips, projecting forward, ascending, diverging, linearfalcate, tips curved, acuminate, (16.5-)20-32.0 x 0.5-1.5 mm; spur toothed, 23-36 mm long, clavate apex 8.0-16.5 mm long. Anther erect, acute, 5-8 mm long, canals slender, 9.0-14.5 mm long. Stigmatic processes clavate to spathulate, projecting forwards and deflexed, sub-parallel, 11.5-18.0 mm long, base adnate to lip. Rostellum 3-lobed, base auriculate, median lobe cucullate, acute to acuminate, margin ciliate, 3.0-5.5 mm long, lateral lobes linear, fused to anther canals, sub-erect to 45°, sub-parallel, 4.5-7.0 mm long. Flowering period: rarely January to February, March to June.
Habitat:
Grassland and savannah, 1000-2200 m altitude.
Notes:
Bonatea volkensiana is distributed inland and is allopatric with coastal populations of B. rabaiensis. This species has a similar posture of the elongate rostellum side lobes (ascending >45°) to B. steudneri and B. lamprophylla, but the morphology and posture of its lower petal lobes and labellum closely resemble Bonatea antennifera Rolfe.
Distribution:
SW. Kenya to N. Tanzania

Bonatea stereophylla (Kraenzl.) Summerh., Kew Bull. 4: 430 (1949).
Homotypic Synonyms:
Habenaria stereophylla Kraenzl., Orchid. Gen. Sp. 1: 959 (1901).
Heterotypic Synonyms:
Habenaria polychlamys Schltr., Bot. Jahrb. Syst. 53: 508 (1915).
Description:
Erect, decumbent or scandent terrestrial herbs, 500-700 mm tall; tubers 2, spreading, elongate-oblong, tomentose. Stem robust, 490-695 x 8-10 mm. Leaves withered at flowering, 15-20, dense, lower sheathing, oblong, acute, 50-60 mm broad. Inflorescence cylindrical, 150 x 80 mm, dense, 10-20-flowered; bracts sometimes withered at flowering, lanceolate to ovate-lanceolate, acuminate, 30-40 mm long. Flowers spreading, greenish yellow, pedicel and ovary sub-erect, 30-35 mm long. Dorsal sepal green, erect, elliptical-lanceolate, galeate, acuminate, 20-25 x 8-10 mm; lateral sepals green, patent, decurved, narrowly-triangular, acuminate to apiculate, base oblique, 20 x 4 mm, adnate to lip and stigmatic processes for 3-4 mm. Petal upper lobe erect, linear, acute to acuminate, 18-20 x 1.5-2.0 mm, adnate to dorsal sepal, lower lobe weakly falcate, linear, acuminate, 17-27 x 1 mm, adnate to claw of lip for 2-3 mm. Lip claw 4.5-6.0 mm, median lobe descending, straight, linear, acute to acuminate, 15-21 x 1 mm, lateral lobes descending, linear, tips curved, apiculate, 21-25 x 1 mm; spur toothed, curved, 28-35 mm long, clavate apex 18-25 mm long. Anther erect, acute, 12 mm long, canals slender, 8-10 mm long. Stigmatic processes clavate, projecting forwards and sometimes deflexed, 15-16 mm long, base adnate to lip. Rostellum 3-lobed, base auriculate, median lobe elongate-rostrate, acute, margin smooth, 8-11 mm long, lateral lobes linear, fused to anther canals, sub-erect to 45°, sub-parallel or slightly divergent, 4-6 mm long. Flowering period: April.
Habitat:
Grassland, to approximately 2100 m altitude.
Notes:
Bonatea stereophylla is a rare species, known from only two collections. This deciduous species has a large distinctive tooth (> 5 mm long) in the spur mouth, an elongate-rostrate rostellum mid-lobe, straight labellum mid-lobe, narrowly triangular lateral sepals, and flowers described as yellowy green (Schlechter, 1915). Morphology suggests the closest allies are B. polypodantha (Rchb.f.) L.Bolus and B. pulchella Summerh.
Distribution:
SW. Tanzania (Ukinga Mts.)

Bonatea steudneri (Rchb.f.) T.Durand & Schinz, Consp. Fl. Afric. 5: 90 (1894).
Homotypic Synonyms:

Habenaria steudneri Rchb.f., Otia Bot. Hamburg.: 101 (1881).
Heterotypic Synonyms:
Bicornella arabica Deflers, Voy. Yemen: 208 (1889).
Habenaria eminii Kraenzl., Bot. Jahrb. Syst. 19: 245 (1894).
Habenaria kayseri Kraenzl., Abh. Königl. Akad. Wiss. Berlin 1894: 62 (1894).
Habenaria ecaudata Kraenzl. in H.G.A.Engler (ed.), Pflanzenw. Ost-Afrikas, C: 152 (1895).
Habenaria philippsii Rolfe, Bull. Misc. Inform. Kew 1895: 227 (1895).
Habenaria arabica (Deflers) Kraenzl., Orchid. Gen. Sp. 1: 184 (1897).
Bonatea eminii (Kraenzl.) Rolfe in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 254 (1898).
Bonatea kayseri (Kraenzl.) Rolfe in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 255 (1898).
Bonatea philippsii (Rolfe) Rolfe in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 7: 254 (1898).
Bonatea pirottae Cortesi, Ann. Bot. (Rome) 2: 362 (1904).
Bonatea arabica (Deflers) Cortesi, Ann. Bot. (Rome) 2: 363 (1905).
Bonatea ugandae Rolfe, Orchid Rev. 14: 368 (1906).
Bonatea sudanensis Rolfe, Bull. Misc. Inform. Kew 1910: 162 (1910).
Habenaria sudanensis (Rolfe) Schltr., Bot. Jahrb. Syst. 53: 508 (1915).
Description:

A large terrestrial herb, 25-1.25 cm tall; tubers several, 3-21 cm long, 1-4 cm diam., subcylindric fusiform or irregular in shape, densely tomentose. Stem erect, robust, leafy throughout its length. Leaves io-2o, up to 19 X 5.5 cm, lanceolate to ovate-elliptic, acute, sheathing at the base, the lowermost sheathlike and the uppermost bractlike. Inflorescence 3-28 cm long, 10-20 cm diam., cylindric to almost corymbose, laxly 3-30- flowered; bracts 2-5.5 cm long, lanceolate, acuminate. Flowers spreading, green and white; pedicel and ovary 4-7 cm long, slender. Dorsal sepal 2-3 X 1-2 cm, elliptic-lanceolate, acuminate, apex often recurved; lateral sepals 2-3 x I-I'5 cm, oblique, ovate-lanceolate, acuminate, the upper margin united for basal I-2 cm to the claw of the lip and the stigmatic arms. Petals bipartite almost to base; upper (posterior) lobe, 1-7-2-7 cm X 1-2 mm, adherent to dorsal sepal, linear, slightly curved; lower (anterior) lobe 3-7 cm X I mm, linear to filiform, adnate to the claw of the lip for 6-20 mm at the base. Lip 3-lobed from a long narrow claw 1 5-3 cm long; side lobes 2.5--2.8 cm X 1-2 mm, spreading; mid lobe 2-3.5 cm x 1-3 mm linear, decurved, sharply reflexed in the middle; spur io-21 cm long, dependent, narrowly cylindric, somewhat swollen apically. Column1-1-8 cm tall; stigmatic arms 2.2-3-2 cm long, clavate, porrect, attached to lip in lower 0o7-2 -2 cm; rostellar side lobes slender, 1-2 cm long, mid lobe in front of the column, 5-8 mm long, helmet-shaped with an acute incurved apiculum, margins ciliolate.
Habitat:
In grassland, amongst rocks, in scrub and at the edges of thickets and forest; I000-2800 m.
Notes:
Bonatea steudneri has variable spur length probably owing to local adaptation to pollinators across its wide distribution range. This species has slightly smaller flowers with similar rostellum structure to Bonatea lamprophylla J.L.Stewart. It differs in its porrect, strongly deflexed lateral sepals and shorter labellum side lobes. Schelpe and Under (1999) Figure 24 C is incorrectly labelled as B. steudneri. The image more closely approximates Bonatea boltonii (Harv.) Bolus, but there is no voucher reference to confirm this.
Distribution:

NE. Sudan to N. KwaZulu-Natal, SW. Arabian Pen.

Bonatea speciosa (L.f.) Willd., Sp. Pl. 4: 43 (1805).
Homotypic Synonyms:
Orchis speciosa L.f., Suppl. Pl.: 401 (1782).
Habenaria bonatea Rchb.f., Otia Bot. Hamburg.: 101 (1881).
Heterotypic Synonyms:
Bonatea densiflora Sond., Linnaea 19: 80 (1846).
Habenaria densiflora (Sond.) Rchb.f. in W.G.Walpers, Ann. Bot. Syst. 1: 797 (1849).
Habenaria robusta N.E.Br., Gard. Chron., n.s., 24: 307 (1885), nom. illeg.
Description:
Erect, decumbent or scandent terrestrial herbs, 95-957 mm tall; tubers 1-8, spreading, elongate-oblong, tomentose. Stem robust, 90-950 x 2.5-14.0 mm. Leaves 4-19, lax to dense, cauline, lower sheathing, blades reduced, oblong-lanceolate to obovate, acute to acuminate, margins entire, smooth to undulate, 26-155 x 110-67 mm. Inflorescence cylindrical, 63-286 x 66.5-165.0 mm, lax to dense, 141- flowered; bracts similar to upper leaves, sheathing, ovatelanceolate to ovate, acuminate to apiculate, 15-53 x 6-23 mm. Flowers spreading, green and white, pedicel and ovary sub-erect, 24-64 mm long. Dorsal sepal green, sub-erect to erect, elliptical to oblongovate, galeate, acute to acuminate, 15-25 x 4.5-9.5 mm; lateral sepals green, patent, slightly deflexed, oblong-lanceolate to ovate, acute to apiculate, base oblique, margins weakly revolute with acute tooth on lower margin, 14.0-29.5 x 5.5-12.5 mm, adnate to lip and stigmatic processes for 5.0-13.5 mm. Petals upper lobe green, erect, narrowly-falcate, acute to acuminate, 13-26 x 1.0-3.5 mm, adnate to dorsal sepal, lower lobe white with green tip, projecting forwards, weakly to strongly deflexed, weakly to strongly divergent, falcate, linear to lanceolate, tip curved, acute to acuminate, (16-)19-39 x (1.5)2.0-5.5 mm, adnate to claw of lip for 3.5-9.8 mm. Lip green,claw 9.0-25.5 mm, median lobe descending, geniculate, apically recurved, linear-lanceolate to narrowly-oblong, acute to acuminate, 9.0-27.5 x 0.5-3.0 mm, lateral lobes descending, diverging, falcate, linear-lanceolate, tips curved, acuminate, 11.5-39.0 x 1-4 mm; spur toothed, 20-57 mm long, clavate apex (13.5-)15.0-32.0 mm long. Anther erect, acute, 5.0-8.5 mm long, canals slender, 9.5-16.5 mm long. Stigmatic processes clavate to slightly spathulate, projecting forwards and deflexed, sub-parallel, (11.5-)14.0-27.5 mm long, base adnate to lip. Rostellum 3-lobed, base auriculate, median lobe cucullate, acute to acuminate, margin ciliate, 5.0-11.5 mm long, lateral lobes linear, fused to anther canals, slightly deflexed to sub-erect 45°, sub-parallel, 2.5-7.0 mm long. Flowering period: June to December, rarely to March.
Habitat:
Grassland, savannah, forest, thicket, fynbos and nama-karoo, but most common in dune forest, from sea level to 1300 m altitude.
Notes:
Bonatea speciosa is a morphologically variable species with a wide distribution on the eastern seaboard of South Africa and an extended flowering period. Populations from northern KwaZulu-Natal and southern Mozambique show a remarkable conformity; these populations flower between June and July, have large flowers, lax inflorescence and low flower numbers (5-7). The rostellum side lobes are distinctive in being semi-erect (45°). Bonatea speciosa is distinct from B. antennifera and B. boltonii with respect to its longer dilated portion of the spur (> 15 mm) in combination with its wider lower petal lobes (> 1.5 mm). The lower petal lobe posture is porrect and weakly to strongly deflexed, with descending labellum side lobes. B. speciosa and B. antennifera are largely allopatric, being constituents of coastal dune forest and savannah vegetation types, respectively, but both overlap with B. boltonii. These three species also differ in their peak flowering period, with the majority of populations flowering from March to May (B. antennifera), June to December (B. speciosa) and December to March (B. boltonii).
Distribution:
S. Mozambique to S. Cape Prov.
References:
La Croix, I. & Cribb, P.J. (1995). Orchidaceae (Part 1) Flora Zambesiaca 11(1); Linder, H.P. & Kurzweil, H. (1999). Orchids of Southern Africa A.A. Balkema; Wild Orchids of Southern Africa Stewart, Linder, Schelpe & Hall 1982; Orchids of Southern Africa Linder & Kurzweil 1999; A taxonomic revision of Bonatea Willd. (Orchidaceae: Orchidoideae: Habenariinae)South African Journal of Botany
Volume 73, Issue 1, January 2007, Pages 1-21
Images:
Click on each image to see a larger version.

Habitat/In situ Habitat/In situ Habitat/In situ Habitat/In situ
Bonatea speciosa 01 Bonatea speciosa 02 Bonatea speciosa 03 Bonatea speciosa 04
Photograph© Cameron
McMaster. Image used
with kind permission.
Photograph© Cameron
McMaster. Image used
with kind permission.
Photograph© Cameron
McMaster. Image used
with kind permission.
Photograph© Cameron
McMaster. Image used
with kind permission.