744. STAUNTONIA ANGUSTIFOLIA Lardizabalaceae. James Cullen

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1 744. STAUNTONIA ANGUSTIFOLIA Lardizabalaceae James Cullen Summary. Stauntonia angustifolia (Wall.) Wall. ex Christenh., formerly Holboellia angustifolia Wall. is described and illustrated. Its recent history in cultivation in Cambridge is discussed. The plant which forms the basis of this article and the plate was received at Cambridge University Botanic Garden from the Royal Botanic Gardens, Kew at Wakehurst Place in 1999, as Stauntonia hexaphylla, collected wild in Sichuan, China by the Expedition to Sichuan (SICH 1755) - details are given below. It was grown under this name, as accession , on the old ticket office at the Bateman Street entrance to the garden. Here it did extremely well, covering the whole southern aspect of the building with its handsome twining stems and shining palmate leaves. It is remarkable in that the male and female flowers are considerably different from each other, and the female flowers, though larger than the males, are less frequently produced and easily overlooked. Indeed, superficial examination can suggest that two different plants, a pink-flowered climber and a white-flowered one, are growing together. It flowered spectacularly in 2006, producing large numbers of racemes of its unusually coloured, vanilla-scented male flowers; female racemes were presumably produced then, but were not noticed by anyone. In 2007 it was decided that the plant should be illustrated for this magazine, but it did not flower in that year, nor did it do so in In 2009 it did flower, but not as spectacularly as it had done in 2006, and material of both male and female inflorescences was collected and studied. In 2009, as part of the reconstruction of the garden s entrance, and the building of a new classroom, the old ticket office was demolished, and the plant destroyed. Emergency attempts to propagate it using cuttings were unsuccessful. Fortunately, Tony Kirkham tells me that the plant is still in existence at Kew and possibly at Windsor Great Park, the High Beeches, Sussex, the National Botanic Garden of Wales, and Sparsholt College, Winchester, all gardens to which the original material was distributed. Curtis s Botanical Magazine 2012 vol. 29 (3): pp The Board of Trustees of the Royal Botanic Gardens, Kew

2 Study of the plant showed quite clearly that it was not Stauntonia hexaphylla, but was a member of the genus Holboellia (as then understood). Stauntonia was traditionallydistinguishedfromholboellia in that its filaments are connate and the perianth-segments are clearly in two whorls, the segments differing in shape and size. Morphologically, our plant was a Holboellia, with a perianth of six free segments (called perianth-segments here), in two whorls, but the segments of each whorl very similar to each other in size, shape and colour. There are also six nectaries, which- in the male flowers are small bright green viscid swellings at the base of the stamens; in the female flowers these look like sterile anthers, but are derived from petals. Using the monograph by Qin (1997) and a recent article on Holboellia in cultivation by Shaw (2009), it was clear that the plant, with its smooth stems, 5 7 leaflets per leaf and anthers shorter than the filaments, belonged to H. angustifolia, and in particular to the type-subspecies angustifolia, whichhasleafletsmorethantwiceaslong as wide. In the circumscription of H. angustifolia adopted by Qin and Shaw, the species has a wide distribution, extending from Nepal and along the Himalaya to western China. Earlier, Chinese plants were recognised as H. fargesii Réauborg, but it is now accepted that these do not differ in any significant details from the Himalayan plants. According to the revision by Christenhusz published in this volume, the genera Holboellia and Stauntonia are better united (see discussion on p. 240 above) and this species becomes Stauntonia angustifolia. In addition to Holboellia fargesii, H. acuminata Lindl., H. marmorata Hand.- Mazz., var. obtusa and var. bracteata Gagnep., of H. latifolia and Stauntonia longipes Hemsl., are all synonyms of Stauntonia angustifolia. Cultivation. The plant is generally easy to grow, rapidly climbing over stumps, buildings and unsightly areas; it can tolerate full sun in Britain, but perhaps semi-shade is more suitable. It seems to flower irregularly, but what controls this is not known. Propagation is by seed (fruits have not been seen in Britain), or by layering. Attempts to propagate it by cuttings have so far been unsuccessful. The plant from which the plate was painted was collected by Kirkham, Flanagan, Howick & McNamara, Expedition to Sichuan (SICH 1755,) - as Stauntonia hexaphylla, on September 21, 1996; China, Sichuan, Nanjiang County, 15 km east of Daba Forest Farm, 1665 m, 316 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

3 Plate 744 Stauntonia angustifolia georita harriott

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5 E N323959; in secondary regenerative woodland. Seed collected from one specimen in a population of more than 100 (approximate population area 10 m 2 ), 10 50% of plants in fruit. Plant to 7 m with spread to 4 m. Species frequent in open, growing in NE aspect, ground steep. Parent rock granite: in coarse granitic soil growing through Quercus glandulifera and Ilex pernyi in mixed broadleaved woodland. Stauntonia angustifolia (Wall.) Wall. ex Christenh., Curtis s Botanical Magazine 29 (3): 264 (2012). Holboellia angustifolia Wall., Tent. Fl. Nepal 1: 25 (1824). Type: Nepal. Wallich 4951 (lectotype K! , duplicates BM!, E, K!, NY!, P!). Stauntonia angustifolia Wall., Cat (1828), nom. nud. Holboellia latifolia var. angustifolia (Wall.) Hook.f. & Thoms., Fl. Brit. Ind. 1: 108 (1872). Holboellia acuminata Lindl., J. Hort. Soc. London 2: 313 (1847). Type: Cult., originally from Nepal. April 30, Stainton 165 (neotype E!, isoneotype BM!). Holboellia angustifolia var. angustissima Diels, Bot. Jahrb. Syst. 29: 343 (1901). Type: China. Sichuan: Nanchuan, Yenkoupien, Bock & Rosthorn 1080 (lectotype O). Holboellia angustifolia var. minima Réaub., Lardizabalées Thésis: 57 (1906). Type: China. Sichuan: Nanchuan, Jingfushan, 1700 m, April 27, Xiong et al (neotype PE, isoneotypes HIB, HQA, IBSC, SZ). Holboellia fargesii Réaub., Lardizabalées Thésis: 59 (1906) et Bull. Soc. Bot. Fr. 53:454 (1906). Type: China. Sichuan: Tchen-Keou, Farges s.n. (holotype P!, isotype P!). Stauntonia longipes Hemsl., Hooker s Icon. Pl. ser. 4, 9: t (1907). Type: China. W. Hupeh. May 1900, Wilson 648 (holotype K!, isotype NY!). Holboellia latifolia var. acuminata (Lindl.) Gagnep., Bull. Mus. Hist. Nat. (Paris) 14:68 (1908). Holboellia latifolia var. bracteata Gagnep., Bull. Mus. Hist. Nat. (Paris) 14: 68 (1908). Type: China. Kouy-Tchéou, Kouy-yang, March 31, 1898, Chaffanjon & Bodinier 2198 (lectotype P). Holboellia latifolia var. obtusa Gagnep., Bull. Mus. Hist. Nat. (Paris) 14: 68 (1908). Type: China. Yunnan: Makongchen?, April 17, 1884, Delavay 888 (lectotype P!, duplicate A). Holboellia marmorata Hand.-Mazz., Anzeig. Akad. Wiss. Wien Math.-Naturwiss. Kl. 58:89 (1921). Type: China. Yunnan: Pudo-ho, 2000 m, March 10, 1914, Handel-Mazzetti 496 (holotype WU, isotype E!). Holboellia angustifolia subsp. trifoliata H.N.Qin, Cathaya 8 9: 114 (1997). Type: China. Sichuan: Wushan, 1500 m, April 27, 1958, Yang (holotype PE). Holboellia angustifolia subsp. obtusa (Gagnep.) H.N.Qin, Cathaya 8 9: 116 (1997). The Board of Trustees of the Royal Botanic Gardens, Kew

6 Description. Large monoecious woody twiner, completely glabrous. Old stems pale grey, somewhat ridged; younger stems shining green. Leaves alternate, distant, spreading at 90 to the stem, palmate, exstipulate but clearly articulated at the base; leaflets usually seven, more rarely three or five, stalked. Petioles and petiolules slightly flattened, petioles 5 12 cm; petiolules arising from a swelling or pulvinus at the top of the petiole, of outer leaflets 5 15 mm, those of the central leaflets cm; leaflets narrowly elliptic to slightly obovate, shining green above, paler beneath, rounded to the base and the blunt apex, cm; young leaves with reddish brown leaflets, hanging, conduplicate when very young, soon becoming U-shaped in section. Male and female inflorescences on the same plant, axillary racemes generally two at each node, towards the ends of the branches. Male flowers generally more numerous and conspicuous than the females, 3 8 in pendulous racemes, smelling faintly of vanilla. Peduncle 7 10 mm, pedicels cm; peduncles subtended by very small brown bracts; bracts otherwise absent. Perianth pale purplish pink overlying green, tubular to somewhat funnel-shaped, of 6 free, valvate segments in 2 series, those of the outer whorl mm, those of the inner cm, all narrowly oblong, those of the inner whorl slightly waisted at about two thirds of the length from the apex. Nectaries (petals?) 6, oblonghemispherical,green ca mm.stamens 6, filaments thread-like ca 9 mm, anthers ca 6 mm, extrorse, each with a small, up-curved, pointed appendage. Pistillode of three green, tapered filaments ca 2 mm. Female flowers superficially very different from the males, 2 4 in ebracteate racemes, occasionally with one or more male flowers apical to the females. Perianth cup-shaped, greenish white, of 6 free, valvate segments in two whorls, those of the outer whorl narrowly ovate, ca 16 9 mm, those of the inner whorl ca 15 8 mm, elliptic. Nectaries 6, whitish, looking like sterile anthers without filaments, curving outwards from under the ovary, ca 2 mm or more. Carpels 3, free, cylindrical, somewhat tapered from the slightly swollen base, ca 1.2 cm, green; stigmas more or less spherical, whitish, viscid. Ovules many in each carpel, marginal. Fruit not set in cultivation, described as a many-seeded, leathery, indehiscent berry, 5 9 cm long, ca 2 cm in diameter, reddish purple, cylindrical or ovoid. Seeds described as 8 6 mm, ovoid, glossy, blackish, more or less compressed (Fig. 1). Distribution. Northern India, Nepal, Bhutan, western China, Myanmar (Burma). Habitat. It is generally found on forest margins, more occasionally on open hillsides or by streams (see collectors notes, above). Flowering time. Late spring, April May, in cultivation. Acknowlegements. I am grateful to Suzanne Cubey and the librarians at the Royal Botanic Garden Edinburgh for help with literature, to Tony Kirkham and Richard Wilford (Royal Botanic Gardens, Kew) for information on the wild origin of the plant and its continued existence at Kew and elsewhere, and to Peter Kerley for information on propagation. 320 The Board of Trustees of the Royal Botanic Gardens, Kew 2012.

7 Fig. 1. Stauntonia angustifolia. A, male flower, side view, 2; B, female flower, side view, 2; C, male flower, side view, with two sepals removed, showing stamens, pistillodes, and nectaries, 3; D, female flower, with two sepals removed, showing staminodes, and one carpel in section, 3. Drawn by Georita Harriott from SICH 1755, cultivated at the University Botanic Garden, Cambridge. REFERENCES Qin, H.N. (1997). A taxonomic revision of the Lardizabalaceae. Cathaya 8 9: Shaw, J.M.H. (2009). Holboellia in cultivation. The Plantsman (New Series) 8: The Board of Trustees of the Royal Botanic Gardens, Kew