Oresbia, a New South African Genus of the Asteraceae, Senecioneae Glynis V. Cron School of Animal, Plant & IEvironmtental Sciences, Universilv ol the Wilwatersrand, Private Bag 3, Wits 2050, South Africa.
[email protected] Bertil Nordenstain Department of Phanerogamic Botany, Swedish Museum of Natural History, Box 50007, SE-104 05 Stockholm, Sweden. h)
[email protected] ts'nliCIT. Oresbiu heterocarp7 Cron & 13. Norlen-stain (Asteraceae, Senecionleae) is described as a newgenus and species from Soumih Africa. Until now thesp)ecies lias been known as Cinnerori. lonlclrroslLessing, although first descril)ed as Se'ncio luntitus1I. f. Both of Ihese names are illegilimiate. Character-istic features of Oresbihm. are the perennial hahil withsessile, non-p)innatifid leaves, which are denselytomentose below, anil the hIleromorphic cypselaewith four-winged ray-floret cypselae. The closestaffiiitlies of Oresbit may )(e with Phanerogloss, B.1Nordenstoll and )possibly also Li mprocephllitI 1B.Nordlelslam, whicl have similar distribution ranges inthe W\eslern C(ape niountains. (Key iwordxs: Asteraceae, (Colinlosilae, Oresbi,, Se-necioneae, Wlestern (ap[e Province. Ongoing taxn sudiesonomic studis on the genus Ciner.riaL. have revealed thle heterogeneous nature of tlheelements have to be remlovedl in order to achievemonophyly (Cron, 2005; Cron et al., in prep.). Twospecies are transferred to and another reinshaled inSenecio IL. (Cron, 2005; Cron el al., in press), andia fourth hlas been maltched to lMesogr(itnl ( opiifoliumI)C. (Nordenstaim & Cron, il ptrep.). Another Iwo aIreplaced in a new genus fl/olUndi Cron, as H.pe/dunculosd (DC.) Cron and 1i. <rgillace<i (Cron) Cron(Cron et al., 2006). The present paper deals with vetaiother misplaced taxonl. which is described as a new"monoltypic geiis.Ores)ia Ilhterocarpa Cron & B. Nortdeistamn, gen. et sp. nov. TYIPE': South Africa. \ Western (Cape: Walerkloofc (Gorge. W f (Ceres. 30 Sep. ] 128. J. Hutchinison & N. S. 'ia//.s 576 (ihootvy')e, K; isotypes, M, , M, ). Figures 1-4; llutch-inson, 1946: 1 16. drawing. lerba )perenniiiis 're ta toieinlosa vel araneosa. l'liaallerna sessilia ellipliha-ov la linon pinnatilfida heirhacea,supra arancll sa el gloalescenrlia. su tlus alholohntinlosa,mnarg ine denliculata vet serrata heviler revoluila. apic'e (ilta,lasi semianmplexicaulia. Peduniiuli terminales 1)mono-veloligovephali suhnudi sparse lhraciolatli: capitula hetcrogamaradiatl sparse calyculal a; iinvolucri bIracleah suhlniscrialaelineari-lanceolatae v\'e(nls acu a nulinlae: recepllaculutll phia-11mi vel sulrc. nvexum la.vec. Flosculi ra(lii Ifniinci glabriflavi. Cvpslar h}eleromorplhae, radii glahrae lua(Irialalac:palp)i selac l )arlielllaie eadluctia . I'losculi disci herlr aphlir o-dili, corolla flava quin(luelol )ala: lolbis o\'alis a ice sub-ciicullatis piapillosis: anllherae iasi sagittat e vel br\ilhrrcandatae, collui filaiiili basi dilatatum; slyli ramni irilusarceis stigmialicis separalis, apice Irinncati p)apillali. CypselahIlis.i exalatae. costis sex hirsulis: pappi sclier numerosaebIarellalae albae caducae. Erect perennial herl)b, to about 30 mi tall; stemslherbac(.:eous, somew\viat woodl at the b)ase(, uil)rainclhed(Ior branchling slariiigly near base. tomenlose to*oblwellbby, glal)rescelnt with age. L'eaves cauliine,allernate, sessile, narrowly oliovate to elliptic orovale, iior-pinnaltifid, lamina 16-66(-10) X 4-23(-28) imm. thickly cob)wel)bby to glalrescent ablove,cliensely whilte-lomentose below: apex acute; marginlentlate to serrale, revolule; leaf-l-ase clasplilng,without auricles. Capilula heterogamous, radiale,usually in twos or threes (rarely as maiyV as 11) perstem, occasionally solitary: peduncl'es 0.5-4 em1 topoIiln of Iralnching, as long as 9 em if unibranched.densel col)bwel)bby,. subtended by lanceolate bracts(1-2.5 cm long) and with smaller bracts along theirlengti, dlislally it le; receplacle flat or slightlyconvex. glabl)ous: ini\oluicre widely caiallllnulate tocup-shaped, calyci(ale with 41 to 7 linear-lanceolalecalyculus bracts 2-4 111111m long: phyllalries sulllllisri-ale. 16 to 20. linear-lanceolate. (5.5-)6.5-7.5 nli nlong. col)welbby to tomentose, glalrescent towalrd theap)ex, ]-Io 3-veined, acuminale, margins narrowlysea(rious. ay florelts 8 to 1.3, female, laliarous; tube2.5-3 nln long, cvlinilrical: limbl) obtlon1g. 5-12 im.,4-veined, yellow. Disc florels herniaplirodilic, 25 lo42; corolla tulbular below, narrowly cmpaiiianlaleabove. 5.0-)6.2 nmm long, yellow: corolla lolbes tri-aiingular-ovale, 0.5-0.7 nmmn long, apically suheucnUl-NovoNx 16: 216-223. Pt nlIJstltt:) ON 26 JI . 2006.
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