Its discovery highlighted in The Plantsman in 2013, this unusual now has a name

formal description is provided here to validate the name based on this specimen, Ogisu 397, which was A new kindly sent to the Herbarium of Royal Botanic Gardens, Kew, by Prof. Wang on loan.

of Daphne Differentiating Daphne and Chris Brickell and Brian Mathew For the following description of D. ogisui detailed observations were validate the name of an attractive and made using both dried and living unusual, yellow-flowered Daphne material. These included floral dissections, which provided an opportunity to check whether this ecently, Roy Lancaster edition of Ogisu (2008), the author species is a Daphne or a Wikstroemia. (2013) described his visit to provided an account of his discovery The distinction between Daphne and R a site in China of a highly of this distinct and apparently new Wikstroemia has previously been distinctive and attractive, yellow- species of Daphne. It included two based on obvious features such as the flowered Daphne species. It had images labelled D. ogisui, a name that number of calyx lobes: four in originally been found by the had not formally been published. Daphne, five in Wikstroemia; and the Japanese botanist and explorer, One specimen from Ogisu’s original arrangement: alternate in Mikinori Ogisu, on 20 March 2005 collection had been deposited with Daphne, opposite in Wikstroemia. near Hegou village in Sichuan, Prof. Yinzheng Wang, a Chinese Current thinking is that although China, growing on steep, dry slopes authority on Daphne, in Beijing but these characters are helpful they are at 550–750m altitude. to date no formal description has only moderately reliable and it is In the enlarged and revised 2nd been provided. At Ogisu’s request a rather the nature of the hypogynal

164 September 2014 disk subtending the base of the that is the defining generic feature. The generic key to in Wang et al. (2007) presents the characters as follows: Daphne – disk absent or annular, cup-shaped, sometimes elongated on one side; Wikstroemia – disk with 2 or 4, very rarely 1 or 5, scales, rarely joined at the base by a very narrow annulus, membranous. From this it seems clear that this recently discovered species should be regarded as a

Daphne. However, it is worth Lancaster Roy repeating from Wang et al. (2007) Daphne ogisui growing in alkaline clay on the side of a limestone valley in Sichuan, China the note which follows the generic description of Wikstroemia: subsessile, alternate, clustered at the Habitat: Open, dry hillside with ‘The separation of Wikstroemia apex of shoots; leaf blade oblanceo­ scrub, soil alkaline clay, from the following , Daphne, late, 6.7–14.5 x 1.2 –3.4cm, gradually 550–750m. is problematic ... In most cases, the cuneate towards the base, apiculate, Distribution: known only from the

Brian Mathew nature of the hypogynal disk is stiff and leathery, dark dull green type locality in Sichuan, China. diagnostic, but even here there are above, pale green beneath, lateral species where the interpretation of veins c.10 each side of the central Conclusion the structure of the disk is difficult ... vein, glabrous above and beneath. It is hoped that this species will A review of generic delimitations in axillary, clustered become more widely known, and the family based on molecular data terminally, each with numerous subsequently more widespread in would be very desirable.’ in condensed racemes so as horticulture. This indeed might be a possible to appear capitate; peduncle sparsely way to clarify this particular bracteate, densely villose, 3–3.5cm Chris Brickell is a former problem, although it would need long; alternate, densely villose, Director of RHS Garden Wisley and to involve a large number of species oblong, c.7–10mm long; floral bracts a former Director General of the RHS from both genera, not just a absent; pedicel very short, the Brian Mathew worked as a representative selection. subsessile. Flowers unscented, yellow botanist at Royal Botanic Gardens, Daphne ogisui differs from other (near to RHS Colour Chart Yellow Kew

Chinese Daphne with 5-lobed, yellow Group 5A); calyx tube narrowly references flowers in its very thick branches cylindric, infundibuliform towards Lancaster, R (2013) Valley of the and prominent, horseshoe-shaped apex,12–13mm long; lobes 5, daphnes. The Plantsman n.s. 12(3): leaf scars. suborbicular, rounded at apex, 4–5 x 189–161 3–4mm. 5, equal, the Ogisu, M (2008) My World of Daphne ogisui C.D. Brickell, filaments c.1mm long, all inserted at . Aboc-sha Inc., Japan B. Mathew & Yin Z. Wang, apex of the calyx tube, the anthers Wang, Y, Gilbert, MG, Mathew, sp. nov. c.1.5mm long, partially exserted from BF & Brickell, C (2007) Daphne. Type: Hegou, Shaping, Ebian Yi, mouth of the tube; ovary fusiform, In: Editorial Comm­ ittee (eds) Flora of China Vol. 13. Sichuan, China, 20 March 2005, sparsely pubescent, strigose at apex, Science Press, Beijing, and Missouri Ogisu 397 (holotype PE, paratype K). 6mm long; papillose, capitate; Botanical Garden Press, St Louis Evergreen to 100cm tall. style very short, c.0.3mm; basal scale Branches thick, c.7–8mm diameter, (hypogynal disc) subtending ovary acknowledgements glabrous in lower part, densely and curved around ovary but on one The authors would like to thank furnished with prominent, horseshoe- side only, more or less square in Roy Lancaster, Mikinori Ogisu, shaped leaf scars, tomentose in the outline, c.0.5 x 0.5mm. Fruit not seen. and, for translation assistance, upper, younger parts. Flowering period: March to April. Yoko Otsuki.

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