A Review of the Litanthus Group of Drimia Jacq. (Hyacinthaceae: Urgineoideae)
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South African Journal of Botany 90 (2014) 96–100 Contents lists available at ScienceDirect South African Journal of Botany journal homepage: www.elsevier.com/locate/sajb AreviewoftheLitanthus group of Drimia Jacq. (Hyacinthaceae: Urgineoideae) with the description of a second species, Drimia stenocarpa, from Western Cape J.C. Manning a,b,⁎, J. Deacon, P. Goldblatt b,c a Compton Herbarium, South African National Biodiversity Institute, Private Bag X7, Claremont 7735, South Africa b Research Centre for Plant Growth and Development, School of Life Sciences, University of KwaZulu-Natal, Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa c B.A. Krukoff Curator of African Botany, Missouri Botanical Garden, P.O. Box 299, St. Louis, MO 63166, USA article info abstract Article history: We review the Litanthus group of Drimia and describe a second species from Western Cape, Drimia stenocarpa, Received 23 August 2013 differing from Drimia uniflora in its invariably solitary leaf, larger flowers with narrower tepal lobes, longer and Received in revised form 20 September 2013 thicker pedicels, and distinctive cylindrical–prismatic capsule longitudinally banded in green and white. Both Accepted 2 October 2013 species are fully described and illustrated and a distribution map is provided. Available online 22 November 2013 © 2013 SAAB. Published by Elsevier B.V. All rights reserved. Edited by GV Goodman-Cron Keywords: Drimia Hyacinthaceae Litanthus New species Southern Africa Taxonomy 1. Introduction infrageneric classification are urgently required. Here we review the species previously treated as the genus Litanthus. The genus Drimia Jacq. sensu lat. comprises ±100 species of largely Litanthus was described by Harvey (1844) for the new species deciduous geophytes distributed throughout Africa and extending into Litanthus pusillus Harv. [now Drimia uniflora J.C. Manning & Goldblatt] Eurasia and the Indian subcontinent (Manning et al., 2004). In this and diagnosed by its 1(2)-flowered inflorescence terminated by a pair broad circumscription it is characterised by the lower floral bracts of subopposite bracts subtending a distinctive, cylindrical, pendulous (at least) bearing a small or large spur and by short-lived flowers flower with well-developed perianth tube [at least twice as long as with a ± gamotepalous perianth. In this sense it includes the genus the tepal lobes]. Typically only a solitary flower develops and the second Urginea Steinh., as well as several smaller groups of species previous- bract is usually empty. An additional unusual character for the genus not ly segregated at generic level. Among the best known of these are commented on before is the prolongation of the anther connective into Rhadamanthus Salisb., Schizobasis Baker, Thuranthos C.H. Wright, a small, translucent, membranous flap.Wehaveobservedthisinno Tenicroa Raf. and the monotypic Litanthus Harv. Additional segregates other species of Drimia with the notable exception of D. cuscutoides have been recognised since then (see Speta, 1998) but have not been (Burch. ex Baker) J.C. Manning & Goldblatt. Litanthus was formally includ- generally adopted. The majority of the southern African species in the ed in Drimia by Goldblatt and Manning (2000), at which time it was still group were last revised by Jessop (1977), supplemented by revisions monotypic. of Rhadamanthus by Nordenstam (1970) and Tenicroa [as Sypharissa Originally described from plants collected near Port Elizabeth, Salisb.] by Obermeyer (1980). Several new species have since been D. uniflora is now known to be widespread in southern Africa, ranging described and even the relatively recent checklist by Manning and from Northern and Western Cape in South Africa to Zimbabwe (Jessop, Goldblatt (2003) is outdated. A modern review of the species and an 1977; Manning et al., 2002). Specimens collected near Papendorp in 1971 by Harry Hall (1906–1986), formerly horticulturist at Kirstenbosch National Botanic Garden, were initially considered to represent a new ⁎ Corresponding author at: Compton Herbarium, South African National Biodiversity species of Litanthus but were subsequently included in L. pusillus [now Institute, Private Bag X7, Claremont 7735, South Africa. fl E-mail addresses: [email protected] (J.C. Manning), [email protected] D. uni ora]byJessop (1977) in his review of the group. Further collec- (P. Goldblatt). tions of these diminutive plants made since then suggest that the initial 0254-6299/$ – see front matter © 2013 SAAB. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.sajb.2013.10.006 J.C. Manning et al. / South African Journal of Botany 90 (2014) 96–100 97 surmise was correct and that the Papendorp plants, along with addition- Distribution and ecology: widespread through the drier, aseasonal al populations from the Breede River in Western Cape, do indeed consti- and summer-rainfall parts of South Africa, from the Gamsberg in tuteaseparatespecies,whichwedescribehereasDrimia stenocarpa for Bushmanland and the Little Karoo through the eastern half of the country its distinctive capsules. These populations differ most strikingly from into southern Zimbabwe but evidently absent from the more arid central D. uniflora in their prismatic, strongly bicoloured capsules on longer, region (Fig. 2). The diminutive plants typically grow in rock crevices or stouter pedicels, and in their narrower tepal lobes. D. stenocarpa is re- rocky cliffs, in seasonally damp situations generally in protected or stricted to the extreme southwestern, winter-rainfall parts of South sheltered locations, sometimes in mats with moss or other dwarf Africa, with true D. uniflora occurring further to the north and east. succulents. We review and illustrate both species, based on herbarium and field Diagnosis and relationships: distinguished from D. stenocarpa by the studies. small, globose bulbs and slightly smaller flowers, 4–6mmlongwith ovate tepal lobes ± 1 mm long, and the ovoid or subglobose, unicoloured – fl 2. Materials and methods capsules ± 3 mm long. The pedicels, 0.5 1mmlongin ower, elongate hardly at all in fruit, reaching at most 2 mm long. Bulbs produce up to fi All relevant types were examined, as well as herbarium material ve threadlike leaves, only rarely just one. from BOL, NBG, PRE and SAM (acronyms after Holmgren et al., 1990), The diminutive size of the species impressed Harvey (1844),who ’ the primary collections of southern African species. Both species were commented on the bulb as being scarcely larger than a good sized pea ‘ ’ also studied in the field. and the scape as no thicker than a bristle . Its relationships puzzled both Zehyer and Harvey (1844). The curious inflorescence with two, op- posite bracts and the solitary, cylindrical flower misled Zehyer into con- 3. Taxonomy sidering it to be a dwarf species of Amaryllidaceae, as evinced by his annotation of his collection with the manuscript name Cyrtanthus 3.1. Key to species of the Litanthus group minimus. Harvey (1844) correctly recognised its family affiliations but was misled by the tubular flower to relate it to the genus ‘Uropetalum’ – fl – 1. Leaves (1)2 5, threadlike; owers 4 6 mm long, tepal lobes ovate, [Uropetalum Burch. ex Ker Gawl.], now a synonym of Dipcadi Medik. ±1 mm long; pedicels ± 1 mm long at anthesis, hardly elongating in fruit and up to 2 mm long; capsules ovoid, ±3 mm long, unicoloured fl greenish or brown. D. uni ora. Additional specimens seen fl – 1. Leaf solitary, terete; owers 6 7 mm long, tepal lobes lanceolate, ZIMBABWE—Belingwe Dist., Mt Buhwa, rock cracks, ±1 650 m, 30 – ±2 mm long; pedicels 1 2.5 mm long at anthesis, elongating markedly Oct. 1973, G. Pope, H. Biegel & N. Gosden 1125 (PRE). – – – in fruit and 5 8 mm long; capsules cylindrical prismatic, 4 6mmlong, NORTH-WEST.—2527 (Rustenburg): Pilanesberg, near Police Station longitudinally banded in green and white. D. stenocarpa. on Genl. Smut's Farm, (–AA), 20 Oct. 1970, S. Venter 1134 (PRE); Rustenburg,nexttowaterfall,(–CA), 1 Feb. 1978, L. Smook 1039 (PRE). 3.2. Species descriptions GAUTENG—2527 (Rustenburg): Krugersdorp Dist., Jack Scott Private Nature Reserve, (–DC), 6 Feb. 1961, M. Weells 2485 (PRE). 2628 Drimia uniflora J.C. Manning & Goldblatt in Goldblatt & Manning in (Johannesburg): Sandton, NE of Frankenwald, crevices in flat rock Strelitzia 9: 712 (2000), as a new name for Litanthus pusillus Harv.: faces, (–AA), 18 Aug. 1951, H. Gilliland PRE62138 (PRE). 315, t. 9 (1844) [non D. pusilla Jacq. ex Willd. (1799)]; Hooker, MPUMALANGA.—2530 (Lydenburg): Carolina, Waterval Boven, 1872. Type: South Africa, [Eastern Cape], ‘shady places in the (–CB), 26 Sept. 1932 m, Van der Merwe PRE32061 (PRE). 2531 woods by the Zwartkop's River, Uitenhage, Cape of Good Hope’,[De- (Komatipoort): 4 mi [6.4 km] from Barberton to Havelock Mine, N cember 1829], Zeyher s.n. (TCD, lecto., designated by Jessop: 308 slopes of Saddleback Hill, (–CC), 17 Oct. 1940, L. Codd PRE36138 (1977); S—ALUKA image!, SAM!, iso.). (PRE). 2730 (Vryheid): Piet retief, Hlangapies, (–BB), Dec. without Deciduous, bulbous herb. Bulb solitary or communal, subglobose, year, F. Van der Merwe 1102 (PRE). 4–10 mm in diameter; outer tunics greyish brown, thinly leathery; FREE STATE.—2827 (Senekal): Clocolan, Mequatlingsnek, (–CD), inner tunics tightly overlapping, white or flushed pink. Leaves synanthous without date, R. Stam PRE32063 (PRE); Senekal Dist., Groot Doornkop, or dry and withered at flowering, (1)2 or 3(–5), erect, filiform–terete, (–DA), 7 Dec. 1931, A. Goossens 932 (PRE). 2927 (Maseru): 18 mi 20–30 mm long, ±0.25–0.8 mm in diameter, glabrous. Inflorescence [29 km], from Hobhouse on Ladybrand road, (–AB), 29 Jan. 1945, 1(2)-flowered, solitary or several in succession; scape erect, 20–30 mm J. Acocks 11186 (PRE). long, minutely longitudinally scabridulous in basal half or ± throughout; SWAZILAND.—2531 (Komatipoort): Havelock Concession, rocky ridge bracts two but only one usually subtending a flower, subopposite, termi- above Komassan River, (–CC), Sept. 1890, E. Saltmarshe 1042 (PRE, SAM). nal, ovate, ±1 mm long, both spurred, spur 0.5 mm long; pedicel de- 2632 (Bela Vista): Ndzindza, Mlawula Nature Reserve, (–AA), 15 Sept.