Three New Species of Metalasia (Asteraceae–Gnaphalieae) from the Western Cape and an Updated Key to the Genus

South African Journal of Botany 84 (2013) 72–82 Contents lists available at SciVerse ScienceDirect South African Journal of Botany journal homepage: www.elsevier.com/locate/sajb Short communication Three new species of Metalasia (Asteraceae–Gnaphalieae) from the Western Cape and an updated key to the genus A. Bengtson a,⁎, A.A. Anderberg b, P.O. Karis a a Department of Botany, Stockholm University, SE-106 91 Stockholm, Sweden b Department of Phanerogamic Botany, Swedish Museum of Natural History, P.O. Box 50007, SE-104 05 Stockholm, Sweden article info abstract Article history: Three new species of Metalasia from the Western Cape of South Africa are described; Metalasia tristis Received 4 July 2012 A.Bengtson & P.O.Karis, a small shrublet from the Groot Winterhoek Mountains, and Metalasia formosa Received in revised form 20 September 2012 A.Bengtson & P.O.Karis and Metalasia eburnea A.Bengtson & P.O.Karis both found in the Langeberg Mountains. Accepted 20 September 2012 The morphology and relationships of the three new species are discussed, and an updated key to the genus is Available online 8 November 2012 provided. Edited by JS Boatwright © 2012 SAAB. Published by Elsevier B.V. All rights reserved. Keywords: Asteraceae Gnaphalieae Metalasia New species Taxonomy South Africa 1. Introduction prep.). The three species are here formalized together with an amended and updated key to the genus Metalasia. The genus Metalasia R.Br. of the tribe Gnaphalieae, Asteraceae, currently consists of 54 species (Karis, 1989; Karis and Helme, 2. Material and methods 2012), with their main distribution in the Greater Cape Floristic Region of South Africa (GCFR; Born et al., 2007) where most are The descriptions and illustrations were based on the type specimens found growing in fynbos vegetation. During recent fieldwork deposited in the Swedish Museum of Natural History, Section of Metalasia material not corresponding to any of the currently recog- Phanerogamic Botany, S, as well as the additional material listed. Mate- nized taxa was collected. After careful examination it was concluded rial was softened in water, dissected, and mounted in Hoyer's solution that the material represents three morphologically distinct hitherto for microscope studies. undescribed species. One species is an erect shrub found in dry fynbos vegetation on the slopes of Tuinskloof near Touwsrivier and in 3. Species descriptions Langeberg sandstone fynbos, the next species is a small shrublet from the Groot Winterhoek Mountains east of Piketberg, and the 3.1. Metalasia tristis A.Bengtson & P.O.Karis, sp. nov third species is a shrub found in Montagu shale renosterveld on the Little Karoo side of the Langeberg (Fig. 1). Recent molecular studies Type: South Africa. Western Cape, Wuppertal (3219): NE of have shown the genus Metalasia to be divided into two clades, mor- Porterville, Farm Waterval, beside walking track above waterfall, phologically separated by the presence of papillose cypselas in one 801 m, (−CC), 5 September 2006, Stångberg, Karis & McKenzie 37 of the clades, the “Metalasia densa group” (Bengtson et al., 2011; (S, holo.; BOL, NBG, PRE iso). Bengtson et al., in prep.). Two of the new species, Metalasia formosa Decumbent, sparingly to well-branched shrublet, up to 0.3 m and M. eburnea, share the distinct papillose cypselas of the high. Branches sprawling to erect, densely whitish tomentose when “M. densa group”, whereas the third, M. tristis, is placed within the young, becoming less tomentose to glabrescent, axillary brachyblasts morphologically more diverse of the two clades (Bengtson et al., in rarely present, less than half as long as subtending leaf, foliage dense to sparse. Leaves involute-ericoid, somewhat twisted, narrowly lance- – – ⁎ Corresponding author. Tel.: +46 08 16 2071. olate 5 10 (14)×0.8 1.2 mm, densely tomentose above, sparsely E-mail address: [email protected] (A. Bengtson). hairy below, apically acute with tips straight to declinate, spreading 0254-6299/$ – see front matter © 2012 SAAB. Published by Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.sajb.2012.09.008 A. Bengtson et al. / South African Journal of Botany 84 (2013) 72–82 73 A B C D E F Fig. 1. Metalasia eburnea (A, D); M. formosa (B, C); M. tristis (E, F). (Photos: A and D by Linda Lundmark; B and F by Annika Bengtson; E by Frida Stångberg and C by Marcus Arnerup). to declinate, straight to slightly curved. Synflorescences 5–12 mm (Fig. 2D, E). Metalasia tristis is most similar to M. divergens (Thunb.) wide, dense, broadly campanulate, with 6 to 15 capitula arranged in D.Don subsp. divergens due to the dense hairy capitula clusters with obscure, hardly distinguishable clusters fused by dense hairs, over- 5-flowered capitula, but M. divergens subsp. divergens has larger, shot by a few bract-like leaves. Capitula 5-flowered, fused by hairs more easily distinguishable capitula and involucral bracts with within clusters and synflorescences. Involucral bracts±13, of±equal glands. Furthermore, Metalasia divergens subsp. divergens is endemic length, erect, densely tomentose for 3/4–4/5 of length, only upper- to the Cape Peninsula. Metalasia serrulata P.O.Karis and M. rogersii most parts visible through the dense tomentum, with broad hyaline S.Moore may resemble M. tristis in habit but both differ in having margins; outermost bracts lanceolate, foliaceous with apical scarious synflorescences with 3-flowered capitula where the outermost lamina, narrow, acute, dark brown; outer bracts lanceolate, apical involucral bracts are considerably shorter than the innermost, and scarious lamina narrow, acute, dark brown; inner bracts narrowly in having rounded pink, petaloid inner involucral bracts. Metalasia oblong to lanceolate gradually becoming somewhat more petaloid, rogersii also differs in that is has much smaller, mostly declinate apical scarious lamina, acute, brown; innermost bracts narrowly ob- leaves with axillary brachyblasts. Metalasia serrulata and M. rogersii long, apically rounded, almost petaloid with a light brown to whitish not only resemble M. tristis, but the three also occur in close lamina. Corolla narrowly cylindrical, 2.8–3.1 mm long, dark purple proximity in the Groot Winterhoek Mountains, Witsenberge, and distally. Cypselas 3-veined (immature). Pappus bristles slightly serrate, Skurweberge. In the molecular study of Bengtson et al. (in prep.) apically clavate with fused cells. (Figs. 1E, F and 2). Metalasia tristis is placed within the “M. divergens group” within the larger and more diverse of the two main clades of Metalasia. 3.1.1. Distribution and ecology Metalasia tristis is known from only two localities on Voorberg in 3.1.3. Additional specimens examined the Groot Winterhoek Mountains near Porterville where it is found South Africa. Western Cape: 3319 (Worcester): E of Porterville, on mountain slopes and plateaus in Winterhoek sandstone fynbos slopes above Farm Dasbos, 791 m, (−CC), 6 Sep 2006, Stångberg, vegetation on well-drained rocky soil (Mucina et al., 2005; Mucina Karis & McKenzie 42 (BOL, K, P, PRE, S); E of Porterville, above Farm and Rutherford, 2006; Fig. 5). Flowering time is from September to Dasbos, 947 m, (−CC), 6 Sep 2006, Stångberg, Karis & McKenzie 44 October. (NBG, S). 3.1.2. Diagnosis and relationships Metalasia tristis is distinguished by its sprawling, decumbent 3.2. Metalasia formosa A.Bengtson & P.O.Karis, sp. nov dwarf habit (Fig. 1E), the tomentose young branches, leaves and synflorescences (Fig. 1F), the synflorescences with capitula fused by Type: South Africa. Western Cape, Montagu (3320): Tuinskloof, whitish hairs (Fig. 2D) and by the involucral bracts with acute, slopes around small valley around farm, 1050 m, (−AA), 12 September narrow scarious, brown laminas visible between the white hairs 2005, Karis & Arnerup 1060 (S holo.; NBG iso). 74 A. Bengtson et al. / South African Journal of Botany 84 (2013) 72–82 Fig. 2. Metalasia tristis, Stångberg et al. 37 (S). A, portion of plant; B, branch with leaves; C, two leaves; D, cluster of capitula fused by dense hairs; E, all involucral bracts from one capitulum, from outermost (upper left) to innermost (lower right); F, pappus bristle with tip magnified (left). Artist: Emma Hultén. Erect, often stout shrub, up to 1.5 m tall. Branches erect, whitish ca. half as long as innermost, erect, acute to mucronate, tips erect or tomentose when young, sometimes with reddish colour, older slightly bent outwards; outermost bracts narrowly lanceolate, acute, becoming less tomentose, with cracking cortex, and the tomentum scarious, brown; outer bracts oblanceolate, acute, scarious brown or peeling off, axillary brachyblasts more than half as long as the sometimes reddish on upper parts, becoming more petaloid inwards; subtending leaf and sometimes elongated into 1.0–1.5 cm long inner bracts oblanceolate, mucronate, subpetaloid, pink or light shoots, leaves persistent for 3 years, older braches with leaf scars, brownish in colour; innermost oblanceolate to oblong, acute to mu- foliage dense. Leaves involute-ericoid, straight to slightly twisted, nar- cronate, petaloid, white. Corolla narrowly cylindrical, 4–5 mm long, rowly lanceolate, 4–7×0.8–1.1 mm, white tomentose above, glabrous purple distally. Cypselas oblong, 1.8–2.1 mm long, 3-veined, brown, beneath, acute, mucronate, tips straight or declinate, straight to papillose. Pappus bristles serrate, apically clavate. (Figs. 1B, C and 3). slightly curved, spreading. Synflorescences 20–30 mm wide, dense, conspicuously branched with capitula arranged in clusters of 5 to 14 3.2.1. Distribution and ecology capitula. Peduncles (0)2–6 mm long. Capitula 5-flowered, somewhat Metalasia formosa is only known from a few localities. It occurs on fused by hairs at the base within clusters. Involucre narrowly valley slopes in Tuinskloof near Touwsrivier, where it is found in cyathiform, apically 2.0–2.5 mm wide. Involucral bracts ±15 in 4 to dry Matjiesfontein quartzite fynbos vegetation, but also in the 5 series, hairy for lower 2/3, gradually longer inwards; outermost Langeberg, growing in Langeberg sandstone fynbos, where it in many A.

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