Othonna ramulosa DC

Magoswana, S. L., Boatwright, J. S., Magee, A. R. & Manning, J. C., 2022, A taxonomic revision of the Othonna coronopifolia L. group (Asteraceae: Senecioneae: Othonninae), South African Journal of Botany 149, pp. 604-616 : 611-612

4. Othonna ramulosa DC . Prodr. 6: 477 (1838); Harv. in Fl. Cap. 3: 330 (1865).

Type: South Africa, [Western Cape], ‘in Africae Capensis distr. Carro’ [ ‘Konstabel’ ], June (without year), Drege [6093 pp.] (GDC-G00473665, holo.—image!; K-000306967—image!, P-0004974— image!, iso.) .

Othonna trinervia DC . Prodr. 6: 477 (1838), syn. nov.; Harv. in Fl. Cap. 3: 332 (1865). Type: South Africa, [Western Cape], ‘in Africae Capensis distr. Carro’, without date, Drege [6093 pp.] ( G-DCG 00473682, holo.—image! ; P-0010020—image!, iso.) .

Shrubs to 1.5 m, stems woody, simple or branched in upper half, branches erect to flexuous, striate, deep red when young becoming pale grey with age, leaf axils cobwebbed. Leaves alternate, mostly fasciculate on short-shoots, blade oblanceolate, sometimes elliptic, narrowed below and petiole-like, 5 - 50 £ 2 - 8 mm, entire or sometimes sparsely to irregularly toothed or pinnatifid, leathery to succulent. In fl orescence of mostly solitary capitula, terminal on stems or short-shoots, sometimes also in upper axils forming loose corymbs; peduncles 20 - 40(- 70) mm long. Capitula radiate, rays and discs yellow. Involucre 8 - 15 mm diam., bracts 7 or 8, lanceolate to elliptic, 6 - 9 £ 2 - 3 mm, connate in basal 1/3 to 1/2. Ray fl orets 7 or 8, corolla tube 1 - 3 mm, limb oblanceolate, 8 - 15 £ 3 - 5 mm; ovary obovoid, appressed-puberulous with white twin-hairs; style branched in upper half. Cypselae ellipsoid-ovoid, 4 - 7 £ 2 - 4 mm, densely appressed-puberulous on ribs with non-myxogenic, white, twin-hairs; pappus 7 - 10 mm long, beige. Disc fl orets numerous, corolla tube 2 - 4 mm long, lobes lanceolate to ovate, 0.5 - 1.0 mm long; filaments 1 - 2 mm long; ovary 3 - 6 mm long; style simple and cone-tipped; pappus of § 10 barbellate bristles, united basally.

Distribution and Ecology: Othonna ramulosa is distributed in the drier southwestern parts of Western Cape, mainly from Swartruggens to Worcester and east along the flats north of the Witteberg to Laingsburg and in the Little Karoo, with one collection from as far east as Uniondale in the Eastern Cape and another inland on the interior plateau near Murraysburg ( Fig. 6 ); on rocky and karroid slopes at elevations above 1 000 m. Flowering from May to September.

Diagnosis: Othonna ramulosa is distinguished by the leaves mostly fasciculate on short-shoots, with oblanceolate or sometimes elliptic blades that are entire or occasionally sparsely to irregularly toothed or pinnatifid, and inflorescences mostly of one or two capitula terminal on the short-shoots along the stem. Older peduncles sometimes become spinescent ( Figs. 1D & 2C 1-C 2 ). The cypselae are non-myxogenic. The species is easily confused with O. coronopifolia , but in that species the capitula are mostly terminal on the branches, often in loose corymbs and only rarely on the short-shoots, and it has myxogenic cypselae. More woody plants of O. coronopifolia are especially difficult to identify as they often develop capitula on the short-shoots, but the peduncles are usually longer than in O. ramulosa , mostly 50 - 150 mm long vs 10 - 50 mm long. The two species are largely parapatric, O. coronopifolia occurs mostly west of the Cederberg and O. ramulosa southeast of the Cederberg. Both species have been collected on the Blinkberg Pass in the Western Cape where their ranges overlap in the northern Swartruggens [ O. coronopifolia, Burgoyne 9297 (NBG) and O. ramulosa Forsyth 256 (PRE)] but they maintain their separate identity. We examined cypselae from the Burgoyne 9297 (NBG) collection and observed myxogenic fruits characteristic of O. coronopifolia , whereas they were non-myxogenic in the Forsyth 256 (PRE) collection of O. ramulosa . Van Breda 4502 (PRE) from between Graafwater and Lambert’ s Bay is an anomalous collection, consistent in morphology with O. ramulosa but with immature fruits and occurring outside the known range of that species. Until the situation is fully investigated, we include it in O. ramulosa . Candolle (1837) described O. trinervia , based on a portion of one flowering stem from the same collection as the type of O. ramulosa , distinguishing it from that species by its leaves apparently with 3 main veins vs just a single vein. We have examined the type and cannot see any difference between the specimens. Numerous collections of O. ramulosa display similar venation as in the type specimen of Otrinervia and we have no hesitation in treating them as one.

3.6. Additional specimens examined

South Africa. WESTERN CAPE: 3218 (Clanwilliam): along Graafwater-Lambert’ s Bay road (- AB), 15 Apr 1982, van Breda 4502 ( PRE); Baviaansberg, Ceres (- BA), 13 Jul 1964, Taylor 5814 ( NBG, PRE). 3219 (Wuppertal): near Wuppertal (- AC), 6 Oct 1897, Bolus 9036 ( BOL); Cederberg, Matjiesrivier Nature Reserve, along road to Pardewater (- AD), 2 Oct 1997, Lechmere-Oertel 651 ( NBG); Blinkberg (- CB), 07 Jul 1983, Forsyth 256 ( PRE); near Wilgenhoutsdrift south of Grootrivier on road to Bokkeveld (- CD), 28 Jul 1973, Taylor 8527 ( NBG); Op die Berg, Rietvlei to Kagga Kamma (- CD), 14 Oct 2008, Cowell, Bennett and Pekeur MSBP 3778 ( NBG); Swartrug, Ceres (- DC), 23 May 1970, Hanekom 1394 ( NBG, PRE); Knolfontein, 60 km NE of Ceres (- DC), 15 Jul 2005, Jardine and Jardine 18 ( NBG); 9 Aug 2006, Jardine and Jardine 346 ( NBG); 12 Oct 2007, Jardine and Jardine 752 ( NBG); 25 Jun 2009, Jardine and Jardine 1136 ( NBG, PRE); 27 Jul 2009, Jardine and Jardine 1138 ( NBG); 13 Sep 2008, Bruyns 11219 ( NBG [2 sheets]); 16 Sep 1964, Taylor 5879 ( NBG); Farm Katbakkies (- DC), 20 Sep 1991, Koekemoer 650 ( PRE). 3220 (Sutherland): Kareekloof (- CD), 24 Sep 1986, Olivier 16 ( NBG). 3221 (Merweville): Prince Albert Road (- DC), 14 Jul 1941, Warren 180 ( NBG). 3319 (Worcester): Karoopoort (- BA), 27 Jun 1941, Compton 11161 ( NBG); 30 Jun 1940, Compton 8905 ( NBG), Esterhuysen 2589 ( BOL); Ceres, 50 km out of Ceres, along R46/R355 Kareekloof Private Nature Reserve, Kleinfontein/Rooifontein farm (- BA), 6 Aug 2003, Murray HMM61 ( NBG); 21 Sep 1941, Compton 11798 ( NBG); Vaalkloof, Ceres (- BB), Aug 1919, Marloth 9178 ( PRE); roadside near Farm Monte Vista, De Doorns (- BC), 4 Jun 1977, Walters 1714 ( NBG); Verkeerdevlei (- BD), 12 Jul 1954, Barker 8284, 8288 ( NBG); 13 Jun 1975, Durand 23 ( NBG, PRE); 29 Sep 1986, Olivier 27 ( NBG); Karoo Garden Veld (- CB), 1 Aug 1975, Bayer 126 ( NBG); 15 miles [24.1 km] N of Worcester (- CB), 4 Jul 1970, de Winter 9296 ( PRE); Ceres, Katbakkies Pass (- DC), 22 Sep 1991, Koekemoer 741 ( PRE); Overhex (- DD), 22 Jun 1980, Walters 2019 ( NBG). 3320 (Montagu): between Jan de Boer and Tweedeside, NE of Voetpadsberg (- AA), 8 Jun 1966, Rourke 436 ( NBG); Farm Cabidu, Laingsburg (- AB), 5 Oct 1941, Compton 10829 ( NBG); Touwsriver (- AC), 1 Jul 1903, Marloth 3223 ( NBG, PRE); 6 Dec 1964, Bayliss 2246 ( NBG); 15 Jun 1961, Barker 9250 ( NBG); 10 Oct 1991, van Jaarsveld 11983 ( PRE); Witteberg, S of Constabel Siding (- AD), 26 Jul 1981, Goldblatt 6094 ( PRE); 3 Aug 1994, Bean 3079 ( PRE); 20 miles [32 km] S of Laingsburg (- BA), 11 Oct 1971, Vahrmeijer 2322 ( PRE); 2 Jul 1942, Compton 13286 ( NBG); 30 Sep 1932, Compton 4055 ( NBG); 9 Aug 1937, Compton 6598 ( NBG); Farm Kleynspreeuwfontein 177, Anysberg Nature Reserve (- BC), 27 Aug 1987, Lloyd 1054 ( NBG); Fisantekraal Valley, Witteberg (- BC), 16 Jul 1923, Compton 2510 ( PRE); Matjiesgoedberge (- BC), 2 Aug 1987, Bands 565 ( NBG); Skerpkrans (- BC), 18 May 1989, van Jaarsveld 10344 ( NBG); Anysberg Nature Reserve (- DA), 24 May 1989, Martin 31 ( NBG). 3321 (Ladismith): Elandsberg, N of Klein Swartberg (- AD), 29 May 1957, Wurts 1502 ( NBG). 3322 (Oudtshoorn): 2 miles [3 km] N of summit of Swartberg Pass (- AC), 13 Sep 1955, Leistner 227 ( NBG); 13 Sep 1955, Acocks 18423 ( PRE). EASTERN CAPE: 3123 (Victoria West) Murraysburg (- AD), Mar 1879, Tyson s.n. ( BOL). 3323 (Willowmore): 5.5 miles [9 km] NE of Uniondale (- CA), 18 Jun 1962, Acocks 22203 ( PRE).

Figures

Fig. 6. Distribution of Othonna ramulosa.

Fig. 1. General morphology of the O. coronopifolia group. A.Habit of O. coronopifolia showing obovate to oblanceolate leaves and capitula with 7 or 8 ray florets; B. Habit of O.leptodactyla showing the linear or narrowly lanceolate leaves and capitula with 7 or 8 ray florets; C1-C2. Habit of O. pteronioides showing the small oblanceolate to elliptic leaves in axillary tufts, the divaricate branches ending in thorns and capitula on short-shoots; D. Habit of O. ramulosa showing the leaves fasciculate on short-shoots and capitula with 7 or 8 ray florets; E. Habit of O. spinescens showing the woody spinescent peduncles, the fasciculate leaves on short-shoots and an involucre with 7 or 8 ray florets; F1-F2 Habit of O. pavonia showing the pinnatisect leaves, the deep red or maroon stems, solitary inflorescence and capitula with 5 ray florets. Photographs: A-E by J. Manning; F1-F2 by L. Magoswana.

Fig. 2. Vegetative variability in species of the O. coronopifolia group (A1-A3, O. coronopifolia) (A1) showing dwarf plants growing along the coast, obovate-oblong, cuspidatemucronate leaves; (A2) plants with capitula on short-shoots, the peduncle mostly 50̅150 mm long; (A3) larger plants mostly with leaves often irregularly toothed or sometimes 3- pinnatifid, often in axillary tufts and on short-shoots; (B1-B2, O. leptodactyla) showing the linear or narrowly lanceolate leaves with linear lobes; (C1-C2, O.ramulosa) (C1) showing leaves mostly fasciculate on short-shoots, oblanceolate, inflorescence terminal on stem, old peduncles ending in thorns; (C2) leaves elliptic, narrow below and petiole-like, inflorescence on short-shoots along stem; (D1-D2, O. pteronioides) showing the divaricately branched habit, tips developing into thorns, the small oblanceolate-elliptic leaves, inflorescence terminal on stems or on short-shoots; (E1-E3, O. spinecens) showing an inflorescence that is either terminal on stems and then a divaricately branched corymb the peduncles becoming woody and spinescent after flowering, or solitary sub-erect capitula terminal on short-shoots and narrowly oblanceolate leaves; (F, O. pavonia) showing the pinnatisect leaves, an inflorescence of few to several capitula in lax corymbs and deep red to maroon stems when young and 5 ray florets and involucral bracts.