222 S. -Afr.Tydskr.Plantk. 1995,61(4): 222 - 225

Ceratocaryum pulchrum, a new restioid from the Bredasdorp plains

H.P. Linder Bolus Herbarium. University of Cape Town, Rondebosch. 7700 Republic of South Africa

Rece ll'ed 29 November 1994; re\'lsed J May 1995

Ceratocaryum pulchrum Under, a new species of from the Western Cape region, is described. It is syntopic with C. argenteum, and a phylogenetic analysis of the genus is performed to show that G argenteum is the sister-species of the new C. pUlchrum. The analysis shows that In the other major clade in the genus the species do not co-occur, but are separated on altitudinal and climatic gradients. Although the mode of speciation of C. pulchrum is obscure, the coexistence of C. pulchrum and its sister C. argenteum may be mediated by different flowering times and different fire-survival modes.

Ceratocaryum pulchrum linder, 'n nuwe spesie in die Reslionaceae van die Wes·Kaap Provin sie, word beskryl. Oil word in dieselfde habitat as C. argenteum aangetref, en 'n filogeneliese analise van die genus is gedoen, wat toon dat C. argenteum die susterspesie van the nuwe C. pulchrum is. Die analise wys dat in the ander hoofklade van die genus die spesie nie sa am voorkom nie, maar dat hulle op hoe en klimatiese gradienle verskil. Hoewel die spesiasie-metode van C. pulchrum nie duideJik is nie, kan die samevoorkoms van C. pulchrum en sy susterspesie C. argenteum verduidelik word deur verskiUende blomtye, en onderskeie brand-oorlewensmetodes.

Keywords: Ceratocaryum. phylogeny, Restionaceae, speciation .

Introduction .Hml cu lmis solidis, a C argenceum culmis brevis, ab ambo bus spiculis solitaris recedit. During a field-trip to the Br~dasdorp plains in October 1994, I found a new species of Ceralocaryum Nees (Reslionaccae). TYPUS.- Bredasdorp, 3 krn from Viljoenshof 10 Elim, all. growing amongst the tall, cacspitose C. argenreum Nees ex 200 m, on sandstones, 26 October 1994, Linder 5906 (BOL, Kunth. The new species was in full flower, whereas C. argen­ hololypus; K, NBG, NSW, PRE, isotypus). reum flowers in au tu mn, and the we re only 0.7 m tall, compared to the 2-m-tall C. argenreum . There is a general im ­ Pl ants caespitose, 0.5--0.7 m tall, tussocks with a basal diameter pression that closely related species rarely co-occur, and thal in of 0. 1-0.3 m and a crown diameter of 0.2-0.5 m. 5-8 the rare cases of sympatry they arc not syntopic. Consequently, mm in diam .. short, somewhat branched. Fertile culms simple. this apparently new species is of some interest, as the plants were tcrete, surface smooth, grecn, 0.5-0.7 m tall, 3 mm in diam. at growing intermingled with plants of C. argenteum. base and 2.5 mm in diam . at the apex. Clusters of sterile branches at thc nodes of the fertile branches are never present. Sheaths Materials and Methods closely convoluted, 30- 35 mm long, obtuse; mucro on sheath The new species was described from fresh mate rial, and information small , very fine and soon lost, 3 mm long, straight and crect; for the ot her species in the genus was obtained from thc herbarium margins narrowly membranous, fimbriate, olivaceous bdow with collections at the Bolus Herbarium , as well as fr om my unpublished a broad brown margin above, upper third of sheath differentiated notes based on field-work over the last 15 years. An atomical data from the lower two-t hirds and decaying in older sheaths . Male were collected from internodal culms, reconsti tu ted in boiling . soapy paniculate, fonning a dense, silvery head; 50--60 water, and sectioned at ca. 20 !-lm by a sledge microtome. The sec­ mm long and 15-20 mm wide. Spathes caducous, obscuring the tions were stained in a combined Safranin and Alcian stain (To livia youn g flowers, coriaceous, concolorous golden brown, acute. & Tolivia 1987), moun/cd m Canada Bal sam, and examined with Male fl owers in thyrses, with no distinct spikclels fonned . brightfle ld and ole optics in a Zeiss Ax.ioskop. taller than flowers, 7-8 mm long including awn, very narrowly Ph), logencLic analyses were conducted using the ie· option (sec li near, 0.4 mm wide, hyaline, acute. Male flowers 6-7 mm long. Appendix l) in Hennig86 (Farris 1988), the data were manipulated Tepals hyaline, linear, glabrous; outer tepa Is 6 x 0.4 mm, inner in DADA, and the cladograms inspected and drawn usi ng CLADOS 4.5 x 0.3 mm. Anthers 1.5 x 2 mm long, included in the flowers; (both written by K. Nixon). The characters used, and the distribution pistillode absent. Female inflorescence with a solitary fertile of the character states, are given in Appendix 1. As outgroups, Can­ , 43- 46 mm long and 8-7 mm wide. Spathes 3-4, IlOl1lois parviflora (Thunb.) PiUans, aristarus (Thunb.) obscuring the spikelet, eventually caducous, coriaceous, like the Krauss and inctlrvara (Thunb.) Linder were used, based male spathes. Spikelet sessile with one ferti le nower, narrowly on the phyl ogenies published by Linder (1991). Nomenclature and elliptical, acute, 30- 35 mm long. Bracts 14- 16, all except one species co ncepts in CeraJocaryum follow Linder (I 985a), who also sterile. taller than flowe r, 20-27 mm long including awn, lanceo­ referenced available futI deSCrip tions of the species. DeSC riptive data late, chartaceous to membranous, body pale purplish with a on the species is stored in DELTA format (Dallwitz 1980; Dallwitz brownish tip, apical margin membranous, aciculate, awn minu tc. & Paine 1986). Female flower without a fleshy pedicel. Tepals membranous, all the same, glabrous, ovate, acuminate, 2 mm long. Results absent. Styles 2, plumose, bases free. Ovary indehiscent with a Ceratocaryum pulchrum Linder, sp. nov., species nova hard woody tuberculate wall, 12-13 mm long and 9-10 mm Ceratocaryum argenrelltn Nees ex Kunth et C. jistll[osum Mast. diam., ovate in longitudinal section and round in cross section, proxima, cujus nucibus tuberculat is scssilibus habet, a C. jisrulo- black. Elaiosome absent. S Afr. J. Bot., 1995,61(4) 223

Phenology, distribution and ecology the upper spathe is ferti le , the other spalhes being sterile with at This new species flowers in October and seed release is probably most relictual spike lets. in the rollowing September. It is known only from the EIim area The other two rel ated species each have autapomorpbies: C. on the Brcdasdorp Plains, suuth-western Cape region. South fislUlosum has hollow culms, and C. argenteum is substantially Africa, w here it is found in fyobos with Pratea compacta R.Br. taller than the other species. It is clear from Ihese characters that (Cowling el al. 1988). on soils derived from Table Mountain C. pulchrum is not only a minimally diagnosable species. in the Sandstone (Thwait!.! s & Cowling 19H7). at an altitude of 200 m . sense of Nixon & Wheeler (1990; 1992) and Davis & Nixon The climate of the area ha'l been described in detail by Thwaites (1992), where the species can be diagnosed by at least a combi­ & Cowling (1987). Prom the dispersed ind ividuals, and the broad nation of characters, but is also an au tapomorphic species with its base of Ihe pla.nts, it appears likely that the y coppict! after fire, own un ique characters (Donoghue 1985; De Queiroz & Dono­ but it has not been possible to type the fi re-regeneration mode. ghue 1988).

Phylogenetic analysis Species coexistence The phylogenetic analysis located a single tree (Figure 1). with a With the exception of C. pulchrum and C. argentewn, no two length of 11 steps, a consistency index of 81 and a reten tion species in the genu s co-occur (Figures 2 & 3). In the case of the index of 88 with the uninform ative characters removed. C.fimbriarum (Kunth) Linder clade. the species are arranged in a gradient from the coast inland (Fi gure 4). The en viron mental Discussion attri bu tes of this gradi ent are complex. C. decipiens (N.E. Br.) Diagnosis of C. pulchrum Linder is found at the lowest altitudes, in the wetter SW Cape mountains. exposed to the wet south-east summer winds, which Cerarocaryum pulchrum is related to C. fisrulosum and C. argen ­ ameliorate the dry Cape summers. C. fimbriawm is in the mon­ tel/til by four synapomorphi es (Fi gure I ). Thc most strik ing syn­ tane zonC, in the lee of the coastal mountains blocking the soulh­ apomorphy is the remarkably large, round, densely tubcrculate east winds; this species is usually found at somewhat higher alti­ nut, the largest in the African members of the family. These nuts tudes th an C. decipiens. C. xerophilum (Pillans) Linder is a typi­ do no t have elaiosomes; when the fruit is released it drops to the cal member of the Cape subalpine belt (sensu Linder et al. 1993), ground and remain s on Ihe soil surface around Ihe base of the where summer drought is extreme, and win ters are coldest. A . There appears to be no means of dispersal, and protection similar pattern is also found in the C. argenleum clade, with C. against predation may be provided by the extraordinarily thick jistu!osum being found at higher altitudes. whereas C. argenleum walls. Although large nut'i without visible means of dispersal and C. pulchrum are fou nd at lower altitudes. with no overlap also occu r in some species of Willdenowia Thuob., the nuts of between the two groups of species. CeralocarYllm are substantially larger. and may be considered to Curiously, spatial distribution, in the sense of biogeography, constitute a distinct and unique fruit type in the Restionaceae does not appear to playa role: the detailed distribution patterns (and possibly in the Cape Flora). These large nuts are consistent appear to be more significant in tcnns of ecological factors such with the large size of the plants of C. jistulosum and C. argen­ as rainfall and alt itude, rather than geographical intervals. team. hut not wi th the much small er size of C. pulchrum. In addi­ Closely related species arc parapatric (e.g. C. fimb riatum an d C. tion, the {cpals of C. pulchrum are strongly apiculate, whereas in decipiens in the Slanghoek Mou ntains), while the wide Dreede the rest of the genus they have on ly a minute central apicuJus. River va lley does not for m the boundary between two related C. pulchrum differs from the other two species by its single fertile spikelet per culm. Typically. Ceralocaryum has several fcrlill.! female spathes, in contrast with C. pulchrum whcre only Hypodiscus Willdenowia C. pulchrum 5 6 8 10

2 1 1 0 9 C. argenteum 7 C. jistulosum o C. xerophilum

11 C. decipiens _ ~':IOO .. D IIOO~- 5 7 CJ .OC)'(IOO .. ... C. IimiJfial'uml L-t-+c., jimbriatum D ·- . 'C. Figure 1 Cladogram with characters optimized on the tree. The characters are numbered according to AppendiX l. Solid bars indi­ cate Uiuque characters, while open bars indicate homoplasious char­ Figure 2 Distribution of C. decipiens (e ), c. jimbriatum (.I..) and acters . C. xerophilwn (0). 224 S .. Afr.Tydskr.Plantk. 1995. 61 (4)

important than the steep ecological gradients lypical of the south­ western Cape Province.

Speciation There have been several enumerations of the modes of speciation in the C.pe Flora (e.g. Goldblatt 1978; Linder 1985b; Cowling 1987). Recently there have been a number of attempts to hypoth­ esize speciation modes for particular taxa based on the patterns of Sister-species coexistence, by superposing the coexistence pat­ terns over phylogenies (i .e. Kurzwcil el at. 1991; Linder & Vlok 1991; Manning & Linder 1992). These studies have suggested that allopatry may playa less significant role than ecological fac­ tors, although both may he involved. 5ll<.:h as when edaphlc fac­ tors arc important (c.g. Goldblatt 19R2). A mode of speciation where the floral morphology is related to pollination fidelity, which has been demonstrated in the orchids (Manning & Lin der 1992; Johnson in prep.), is not immediately relevant to these wind-poll inated Restionaccae. The sister-species analysis method docs nol produce an 'obvi­ ous' answer for the mode of speciation of C. pulchrum. It is cur­ - ~,­ (::::.;] 100,).1600 .. rently syrnpatric with its sister-species, which suggests that it 0:101)--" either evolved syrnpatrically from the C. argenteum- c. fistula­ 0'- sum clade. or thai C. argenteum estahlished its sympatric distri­ bution by post-speciation dispersaL More in terestingly, it is also synlopic with C argenteum, which su ggests the much more Figure 3 Distribution of C. argenteu11I (e), c. fisrulosum (0) nnd unlikely situation of syntopic speciation. This has been suggested C. pulchrum ( ... ). for a few orchid species le.g. CO I)lc ium nigrescens Sond. (Kurzwcil et at. 1991) and Disperis Sw. (Manning & Linder species. The small impacl of geography relative to ecological 1992)]. A further possibility is that the shift in fl owering time factors has also been described in other genera of the Rcs­ may be associated with a shift in fire-survival mechanism, with tionaccae (Linder & Vlok 1991). as well as in several groups of C. pulchrum coppicing after fire, whereas it s sisters reseed after orchids (Linder 1980, 1981). This would be consistent with fire. The importance of these shifts has been highlighted by Linder (1985b). who argued that allop.try was possibly less Linder & Vlok (199 1) for Rhodocoma Nees, while Schutte el ai.

C.lter ophilu m 2500

2000

C.listulosum !· >• • ~ E 1500 'y; ... .. f • C.pulchrum ,• ~ .:' .. • ~ c .. ! " > I c C .• rgenteum , ~ . o 1000 ~• ~ " ~ ·•0 ·• 0 < ., Q · 3 c •" • :::', • •0 •0 ~ E ~ < < ~ ~ "'0 ~• • 500 c"• c , ;; ~ c Q r-L " ~ 0 o ! ~ x " ;; " " : ~ ! ~ ,;::,L______l\- __7'''''~w: . :;:::i,- ;3..:;:, ·=~==="::.. ;~.' J ..: .==: ______

Figur e 4 Claclogram overlain over two transects through the distribution range of Ceratocaryum: the left-hand transect runs from Betty's Bay to Matroosberg, while the right-hand one runs from Agulhas to the Langeberg at Swcllendam. The altitudinal range is indicated on the left­ hand margin, S.Afr.J.1l0l., 1995,61(4) 225

Fire Flowering KURZWEIL, H., LINDER, H.P. & CHESSELET, P. 1991. The phylo­ ~ fislufosum unknown Spring geny and evolution of the Pterygodium- Corycium complex (Coryeii­ ~ argent8um reseeds Autumn nae, Orchidaceae). Pl. s),st. Evo/llt. 175: 161-223. LJF pulchrum ?coppice Spring UNDER, H. P. 1980. An annotated revision of th l! genus Schlzochilus ?coppice Spring Sond. (Orchidaceae). 1/ S. Afr. Bot, 46: 379- 434. II X8 hilum 0" I[ coppice C declplens Autumn Ul\TDER, H.P. 1981. Taxonomic studies in the Disinae (Orchidaceae). F fimbffatum coppice Unknown IV. A revision of Disa Berg. sect. Micranthae Lind!. Rull. lard. bOlo Figure 5 Cladogram of Ceratocaryum, with time of flowering an naln. BeLg. 51: 255-346. mode of fir~ survIval indlcateJ. LINDER, H.P. 1985a. Conspectus of the African species of Res­ tionaceae. ROlhatia 15: 11 - 76. LINDER, H.P. 1985b. Gene flow, speciation, and species diversity pat­ (in press) have explored Ihe biological attributes of this distinc­ terns in a species-rich area: the Cape Flora. In: Species and speciation, ti on . Another isulating mechanism may be flowering time. ed. ES. Vrba, pp. 53-57: Transvaal Museum Monograph 4. Linder (1090) showed that flowering time may be important for LINDER, H.P. 1990. A morphological study on the separating clusely related species in the Thamnochortus erectus erec/us complex (Reslionaceac). S. Afr. 1. BOI. 56: 443-449. (Thunb.) Mast. complex. The possible roles of flowering time UNDER, H.P. 1991. A review of the southern African Restionaceae. and fire regeneration mode arc shown in foigure 5. Too much COlltr. Bnlus Herb. 13: 209- 264. information is st ill m issing to allow confident interpretation, but UNDER, H.P. & VLOK, 1. H. 1991. The morphology, and it seems as if C. pulchrum is separated from the co-occurring C evolution of Rhodocoma (Restionaceae). Pl. sySl. Evolut. 175: 139- argenteufIl by both fl owering time (providing an isolation mecha­ 160. ni sm), as well as fire regeneration mode (providing a different LINDER, H.P., VLOK, J.H., MCDONALD, DJ .. OLIVER, E.G.H., ccologil.:al niche). The speciation event which separated C. jisfu ­ BOUCHER, C, VAN WYK, B-E. & SCHtrITE, A. 1993. The high IOSIlI1l and C. argenfelllll from C pulchrum cannot be completely altitude flora and vegetation of the Cape Aoristic Region. South reconstruClcd, due to incomplete knowledge about the biology of Africa. Op. HOI. 121: 247-261. C.jislulosltm. Similarly, the geographical basis for the speciation MANNING, J.e. & LINDER, H.P. 1992. Pollinators and evolution in Disperis (Orchidaceac), or why are there so many species? S. Afr. 1. cannot confidently be determined. Although C. pulchrum and C. Sci. 88: 38-49. argenleum are currently sympatric, the possibility that C. argen­ NIXON, K.c. & WHEELER, Q.D. 1990. An amplification of the phylo­ tellm established its current distribution range by dispersal cannot genetic species concept. Cladistics 6: 21 1-223. be ruled Qut, and the initial speciation could have been allopatric. NIXON, K.c. & WHEELER, Q.D. 1992. Extinction and the origin of species. In: Extinction and phylogeny, eds. Novacek, M.J. & Wheeler, Conclusion Q.D., pp. 119-143. Columbia Univt!rsity Press. New York. C pulchrum is m orphologically distinct from the other species in SCHUTJ'E, A.L., VLOK. J.HJ. & VAN WYK, B-E. (in press). Impor­ the genus. Its coexistence with its syntopic sister species, C. tance of growth fonn in the eCOlogy, taxonomy and evolution of fyn­ argenleum, appears to be facilitated by a shift in flowering time, bas legumes. Pl. sy.rt. Evo/at. and possibly by coppic ing after fire rather than re-establishing its THWAlTES. R.N. & COWLING, R.M 1987. Soil-vegetation relation­ populations from seed . Detailed phylogenetic analysis, in combi­ ships on the Agulhas Plain, South Africa. Calella 15: 333-345. nati o n w ith an analysis of ecological condit IOns of the species, TOLIVIA, D. & TOLIVIA, J. 1987. Fasga: 3 new phytochromatic fo r can eilst substantial light on how the very ric h nora of the south­ si multaneous and differentiaJ staining of plant tissue. 1. Microsc. 148: weSlern Cape was eSlablished and maintained. 113- 11 7.

Acknowledgements Appendix 1 Characters used for the phylogenetic analysis This research was funded by the Foundation for Research Devel· Character list. Characters with asterisks are autapomorphies and were upment, Pretoria. not used in calculating the tree statistics. All multi slate characters were used additively. References 1. Rhizomes: long (0); short (I). COWLING. R.M. 1987. Fire and its role in coexistence and speciation in 2. Culms: not fistular (0); fistular (1)*. Gondwanan shrublands. S. Afr. 1. Sci. 83: 106-112. 3. Spathes: acute, paJe (0); long-acuminate, dark (1). COWLING, R.M., CAMPnELL, n .M., MUSTART, P., MCDONALD, D., 4. : numerous (0); solitary (1 )*. JARMAN, KL. & MOLL, E.1. 1988. Vegetation classification in a flo­ 5. Nut wall: smooth (0); tuberculate above (1); ruberculate all over (2). ristically complex area: the Agulhas Plain. S. Afr. 1. Bot. 54: 290-300. 6. Nut outline: barrel shaped (0); round (I). DALLWITZ, MJ. & PAINE, T.A. 1986. Uscrs guide to the DELTA sys­ 7. PemaJe tepaJs: broadly oblate, overlapping (0); oblong. not overlap- ping (I). tem - a general system fo r processing taxonomic deSCriptions, 3rd 8. FemaJc tepals: apiculatc (0); long apiculate (I). cdn. CS IRO Australian Division of Entomology Report 13. 9. Culm diam: 2-4 mm (0); 6-8 mm (1). DALLWI17.. M.1. 1980. A generaJ system for coding taxonomic 10. Elaiosome: absent (0); present (I). descriptions. 1ilxofl 29: 41-46. II. Elaiosome: short < ca.l/lO of nul> (0); long < ca.1/3 of nut > (1)*. DAVIS , 1.1. & NIXON, KC. 1992. Populations, genetic variation, and the dc]jmit ation of phylogenetic species. Syst. Bioi. 41: 421-435. Distribution of Ihe character states, as listed above DE QUEIROZ, K. & DONOGHUE, MJ. 1988. Phylogenetic systemat­ 5 10 ics and th e species problem. Cladistics 4: 317- 338. Caflnomois parviflora 10000010010 DONOGHUE, M.J. 1985. A critique of the biological species concept Hypodiscus aristatus 100000]0010 and recommendations for a phylogenetic alternative. The Bry%gisl \Villdenowia glomerata 100000]0010 88: 172- 181. Ceratocaryum argentewn 10002101100 FARRIS, J.S . 1988. Hennig86 Reference. Published privately. Ceratocaryam pulchrum 100]2101000 GOLDDLATf, p. 1978. An :malysis of the flomof Southern Africa: its char­ Ceratocaryum Jistulosum 11002101100 acteristics. relationships, and origins. Ann. Mo. bot, Gdrz 65: 369- 436. Ceratocaryum decipiellS 00100000011 GOLDBLATT, P. 1982. Systematics of Freesia Klau (lridaccac). 11 S. Ceratocaryumfimbriatum 0010]010010 Ai' BOI, 48: 39-9 I. Ceralocaryum xerophilltm 00000000010