zyxwvu zyxwvuts Taxonomic notes on Polygonaceae fiom southern tropical Afkica SANTIAGO ORTIZ*, F1.S hboratobo de Botanica, Facttltade de Farmaria, Universidade de Santiago, I5706 Santiago de Coinpostela, Spain JORGE A. R. PAIVA, F1.S Departamenlo de Bolanica, Universidade de (himbra, 3049 Cbinibra, Portugal zyx zyx zyx zyxwvutsrqpon zyxwvuts A s part of taxonomic studies of the family I'olygonacrac For the Flnrn <nniht.tinrn projc*ct.t i v o new species from southrrn tropical Africa arc dcscrilxd: Persicaria nogueirae S. Ortiz & I'aiva, from %aniliaand Angola, and Oxygonum annuum S. Ortiz & Paiva, from %anil)iii. I n addition, two IICW c(imlinations are proposed: Po!tpnii/n glomtrn/urrr 1)ammrr is transfcrrrd t o thr genus Pti:tit.arin as Persicaria glo-ata (Dammrr) S. Ortiz & I'aiva, and I'trsirnnu nt/tiriin/n (R. Hr.) Sojiik subsp. q/nrntm K.1...\Vilson is rriiamcd Persicaria madagascariensis (Xlrisn.) S. Ortiz & l'aiva. 0 I!#!)!) 'l'lir Liiiiicmi Scwicty (11 ~ A I I I ~ I I I ~ I ADDI'I'IONAL KEY LVORDS: Ptr.\irnrin 0 , ~ g n i i z m- systematics CX )NI'LNl~S Introduction . . . . . . . . . . . . . . . hlaterial and methods . . . . . . . . . . 1)rscription . . . . . . . . . . . . . . . Persicaria nogueirae S. Ortiz & I'aiva sp. nov 'Two new nomenclatural comlinations in Penicorin Oxygonum annuum S. Ortiz & Paiva sp. nov. Acknowlcdgemrnts . . . . . . . . . . . . References . . . . . . . . . . . . . . . Appendix . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167 I68 I68 I (ill I ti!) I72 I73 I75 I76 During our studies of the family Polygonaceae for the Flora <amhp.siaca project, largely involving material from BM, COI, K, LISC, LISJC, LISU, LMA, LhIU, * Chrrcsponding author. E-mail: hvsortiz@usc.cs 002.1 407.1/9I~/l00ll~7+ I0 $SO.OO 167 I68 zyxwvutsrq zyxwvut zyxwv zyxwvuts s. o m z AND J. A. R. PAIVA MAL, NDO and SRGH (Holmgren el al., 1990) we have found various specimens whose morphological characters do not correspond with those of the taxa described to date, prompting us to describe two new species in the genera Persicaria and Ovgonum. Additionally, the approach adopted in the Flora Zambesiaca with regard to the systematics of the genus Pobgonum s m u lato requires two new combinations affecting the genus Persicaria. MATERIAL AND METHODS zyxw zyx For the morphological descriptions all material was studied with the aid of a light microscope. For examination of tepal epidermis, well-developed open flowers were selected. Inner tepals were mounted on aluminium stubs, and coated with a c. 30 nm layer of gold for study with a scanning electron microscope (SEM) (LEO 435VP), operating at 15 kV. Terminology for the cell types and surface sculpturing patterns of the tepal epidermis follows Hong, Ronse Decraene & Smets (1 998). DESCRIPTION Persicaria nogueirae S. Ortiz & Paiva sp. nov. Herba perennis, nodis basalibus radicantibus. Caulis glaber. Folia omnia limbo hastata, (20-)40-70(-100) x (4)5-7(-14) mm, glabro quidem, subsessilia vel brevissime petiolata-petiolo non ultra 10 mm, glabro aut pilis nonnullis reflexis et strigosis munito-atque ocrea potius glabra, tantum basi margine pilis nonnullis reflexis et strigosis praedita. Inflorescentia 100- 160 mm longa, pedunculis atque bracteis glabris, floribus certe solitariis, pedicellis glabris pedicellatis tepalis 5 non glandulosis, staminibus 8, stylis 3. Fructus (immaturus) trigonus. PERENNIAL HERB erect, 80-100 cm tall. Stems branched, reddish-brown, glabrous, rooting at lower nodes. Ocreae (-7)9-18(-25)mm, acute or subacute at the apex, with a basal ring of bristly, reflexed hairs up to 2.5mm long at the base and sometimes with short apical cilia and hairs along the veins up to 0.5 mm long. LEAVES alternate, subsessile or with a petiole up to 10 mm long, sometimes with several bristly hairs; lamina (20-)40-70(-100) x (4-)5-7( 14)mm, sagittate, with an acute apex, the basal lobes up to 10 mm, dull green, the upper surface darker than the lower, glabrous. INFLORESCENCE a panicle, 100-160 mm long, very lax, slender, & dichotomously-branched; peduncles glabrous; bracts 2-3(-3.5) mm long, sometimes with an acuminate apex, surface glabrous, with apical cilia up to 0.5 mm long. Flowers solitary, only one per bract; pedicels up to 2 mm long, not cxceeding the bracts, glabrous. PERIANTH 3-3.5 mm long, eglandular, white with purple to pinkishmauve tips; tepals 5, longer than the tube, 2/3-3/4 of the perianth length, unequal, the 2 external tepals c. 1.8 mm wide, broadly ovate, the 3 internal tepals c. 1 mm wide, lanceolate, both with rounded to obtuse apex. STAMENS 8, unequal in length, 1-2.5 mm long, included; anther 0.3-0.4 mm long. STYLES 3, 1 mm long, united for zy zyxw zyx zy zyxwv NOTES O N AFRICAN POLYGONACEAE I69 half of their length, sti<pas capitate. Nut (immature) c. 2 x 1.5 mm, trigonous (?) (Fig. I). Epmology. Dedicated to Isabel Nogueira from the University of Coimbra, who started the study of the family Polygonaceae for Flora Zambesiaca, and died in 1994. Qpe: Zambia, NW Province (W Division of F.Z.), Mwinilunga District, Chitunta Dambo, 25 km from Mwinilunga on road to Kalene Hill, 1 1'30' S, 24'23' E, 1390m alt., grassy dambo, 21.i.1975, Brummitt, Chisumpa €5' Polhill 13954 (K. holotypus). Other material examined. Angola, Moxico, about three quarters of a mile east of Lusavo Falls, among sedges, in swamp, 13.i. 1938, Milne-Redhead 41 I0 (K, BM). Without doubt, the most morphologically similar species is R strigosa (R. Br.) Nakai, distributed throughout much of tropical Africa, Madagascar and southern Africa, and also present in Asia and Australia. The new species can be distinguished from R strigosa by the characters listed in Table 1. These characters are highly stable. In particular, it should be stressed that stamen number and style number in R strigosa are invariant, according to both our own observations and reports in the literature (Baker & Wright, 1909; Robyns, 1948; Graham, 1958), despite the fact that many species of the genus Persicaria show variability in these characters. Besides the cited sexual characters, Persicaria nogueirae shows a number of clear morphological differences from R strigosa, notably the pattern of grouping of flowers in the inflorescence, which is one of the principal diagnostic characters used to separate rl glomerata (Dammer) S . Ortiz & Paiva from R strigosa (Dammer, 1919; Robyns, 1948; Graham, 1958). The other major differences relate to pilosity (of leaves, stems, floral peduncles, etc), which has been widely used as a diagnostic character in this genus (see for example Baker & Wright, 1909; Graham, 1958; Webb & Chater, 1964; Wilson, 1990). In addition to the specimens from Zambia and Angola we have seen a number of similar specimens, especially as regards inflorescence morphology, from Tanzania [Renzovoite €9Abdallah I889 (K)] and Uganda [Egeling 504 (K)], though the latter specimen has linear-elliptic upper leaves. Furthermore, Graham (1 958) reported specimens from tropical East Africa with characters deviating from those of Pobgonum strigosum R.Br. ( R strigosa) and coinciding with those of R nogueirae. Taken together, this strongly suggests that R nogueirae is present in that area. The tepal epidermis of R nogueirae has rectangular cells, with straight or nearly straight anticlinal walls and faint longitudinal cuticular striae (Fig. 2). This pattern is similar to those of the sections Echinocaulon (to which R nogueirae belongs) and especially Cephalophilon (Hong et al., 1998). zyxwvut Two new nomenclatural combinations in Persicaria Like Haraldson (1978) and Ronse Decraene & Akeroyd (1988), we consider that the anatomical and morphological differences between Pobgonum L. and Persicaria Miller justify their consideration as separate genera. A number of authors, including Gross (1 9 13) and Nakai (1 926), and more recently Hara (1 966), Sojak (1 974), Ronse Decraene & Akeroyd (1988) and Wilson (1988, 1990), have proposed the transfer to Persicaria of species originally assigned to Polyg.onum. However, one of the species S. zyxwvutsrq zyxwvuts zyxw OKI’IZ /\NI).J. h. K. I’AI\’A B zyx zyxwv Figure I . Persicaria nogueirae sp. nov. A, habit. B, Icaf. C, orrra and Iiasal part of the I d . 11, iiiflorcsrenre. L, Hower and bract (all of Brummitt, Chisump.? & Poltiill 13954, I(). zyxwv zyxwvutsrq zyxwvu zyx zyx NOTES O N AFRICAN POI.Y(X)NACEAE 171 ‘Lwi.e I . l’riiicipil iiiorpliological diflircnccs bctwccn Persicuriu nogueirue sp. nov. a i d f! .i/njpin. C :Iiar;ictc.rs/sprcii,s k? nogueirae sp. nov. zyxwvuts ligurr 2. SEhl micrograph of thc inncr trpal cpidcrmis rrlls of Persicaria nogueirue sp. nov. (hliliir-Kcdhcad + I 10, K). Scalr bar = I0 nini. studied by us, Po!xqonum glomerntum Dammer, has not been transferred to Persiixria, to which it clearly hclongs. We therefore propose the following ncw combination. zyxw Persicaria gZomerata (Dammer) S. Ortiz & Paiva comb. nov. E Pobgonum glorneratum Damtner in Feddes Repert. Spec. Nov. Regni Vcg. 15: 386 ( 1 9 19) (hasion.). z Truellum glomeratunz (Dammer) Sojik in Prcslia 46: 146 (1974). --Po!vgonurn pedunculare sensu auct. afr., non Wall. ex Mcisn. Two of the taxa present in the arca covered by the Flora Zambesiaca, first identified as separate species of Polygonurn (Rpulchrum Blume and P setosuluni A. Rich.) by Graham (1958), are morphologically very similar and often confused. Wilson I72 zyxwvutsrqp zyxwv zyxw zyx zyxwvuts S. ORTIZ AND J. A. R. PAlVA zyxwv zyxwvutsr zyxw (1990) transferred the African specimens assigned to these taxa to Persicaria, as Persicaria attenuata (R.Br.) Sojak subsp. aficana K.L. Wilson and Persicaria setosula (A. Rich.) K.L. Wilson, respectively, both widely distributed in Africa. The morphological differences between the two taxa (principally in peduncle and leaf pilosity, although also petiole length, leaf length and perianth:nut size ratio) are in fact no more marked than those between I? attenuata subsp. aficana and the other two subspecies of R attenuatu, subsp. attenuata and subsp. pulchra (Blume) K.L. Wilson, from Asia and Australia (differing from subsp. aficana in petiole length, leaf pilosity, density and size of ocreal cilia, ocrea surface pilosity, perianth colour and nut morphology). In view of this, one possibility would be to consider R setosula as a fourth subspecies of I? attenuate. However, the two taxa (I? attenuatu subsp. aficana and I? setosula) have similar distributions and similar ecological characteristics, arguing against this approach. We favour a second possibility: consideration of R attenuata subsp. aficana as a separate species. A similar approach has been followed with Persicaria barbata (L.) H . Hara, a palaeotropical taxon that is likewise morphologically close to I? athuata and I? setosula but was considered as a separate species by Wilson (1990). We therefore propose the following new combination. Persicaria madagascariensis (Meisn.) S. Ortiz & Paiva comb. nov. = PoCygonum poiretii Meisn. var. madagmcarimse Meisn., Monogr. Polyg.: 79 (1826) (basion.) = PoCygonum madagascariense (Meisn.) Meisn. in DC., Prodr. 14: 113 (1856). = Persicaria attenuata (R.Br.) Sojak subsp. aficana K.L. Wilson in Kew Bull. 45: 629 (1 990). -PoCygonum pulchrum sensu auct. afr., non Blume Oxygonum annuum S. Ortiz & Paiva sp. nov. Herba annua. Caules glabri aut glabrescentes. Folia ocreis (4-)5-6(-9) mm longis, glabris aut glabrescentibus, limbo quidem lineari, (8-)20-30(-60) x 0.3-0.7(- 1) mm, in apice vel prope apicem ocreae inserto. Flores hermaphroditi, (4-)5-6 mm longi, tepalis 5, 1-2 x 0.5-0.7 mm, inaequalibus, albis, nonnumquam extus roseis. Fructus ellipsoideus, 4-5 x 2.3-2.5 mm, striis longitudinalibus circiter 12 atque rugis transversalibus numerosis, glaber aut pilosus. ANNUAL HERB, erect, up to 40 cm tall. Stems branched, angular-striated, greenish, reddish at the base, glabrous to glabrescent, with simple, white, 10-mm-long hairs at the base. Ocreae (4-)5-6(-9) mm long, often 3-4 dentate at apex, surface glabrous or somewhat pubescent, particularly those of the lower part of the stem, apex glabrous or with fringe of simple, white, c. 0.2mm long hairs. LEAVES arranged in a basal rosette and alternate along the stem, inserted at or up to 1 mm from the apex of the ocrea, (8-)20-30(-60) x 0.3-0.7(-1) mm, narrowly linear, glabrous or with hairs like those of the stem. INFLORESCENCE 10-2 1 cm long, elongate, slender, bracts 3-4(-5)mm long, sometimes with an acuminate apex up to 1 mm long, surface glabrous to pubescent, with short apical cilia c. 0.03 mm long. 3(-4) flowers per bract, l (-2) flowers per bract open at the same time; pedicels erect, 3-5 mm long, exceeding the bracts by 1.5-2.5 mm, glabrous to pilose. FLOWERS hermaphrodite, homostylous (or not conspicuously heterostylous), (4-)5-6 mm long. PERIANTH with zyxw zy zyxwv zyxw zyx zyxwvu zyx zyxwvu NOTES O N AFRICAN POLYGONACEAE I73 5 unequal white tepals, 1-2(-2.5) x 0.5-0.7 mm, with acute apex, tinged with pink at the abaxial surface, particularly the outer ones. STAMENS 8, unequal in length, 0.5- 1.5 mm long, included, anther 0.5-0.7 x 0.3-0.5 mm. STYLES 3, c. 1.5 mm long, with stigmas capitate. FRUIT 4-5 x 2.3-2.5 mm, ellipsoid, with c. 12 longitudinal ridges and numerous transversal wrinkles, glabrous to pubescent with simple hairs up to 0.2 mm long (Fig. 3). q p e . Zambia, W Province (B Division of F.Z.), Barotseland, Mongu District, Mongu, sandy woodland, 12.i. 1966, E.A. Robinson 6792 (K, holotypus). Other material examined. Zambia, W Province (B Division of F.Z.), Barotseland, Mongu District, Mongu, sandy roadside, 22.xii. 1965, E.A. Robinson 6747 (K). Ibid., 77 km from Mongu on road to Kaoma, Guibourtia, Baikiaea woodland and Kalahari sand, 30.i.1975, Brummitt, Chisumpa &3 Polhill 14171 (K). NW Province (W Division of F.Z.), Kabompo District, near Lusangwa, 172 km S of Mwinilunga on Kabompo road, 1 1 10 m alt., 26.i.1975, Brummitt, Chisumpa €3’Polhill 14132 (K). The most morphologically similar species is probably 0. lineare De Wild, from the Congo and Angola, which likewise presents linear leaves and ellipsoidal fruits. However, this species can be differentiated from 0. annuum by the absence of transverse wrinkles on the fruit: according to Graham (1957), this character is of great diagnostic value within the genus. Furthermore, 0. lineare is conspicuously heterostylous, has ocreae with generally longer apical fringed bristles, leaves linear to elliptical, (0.5-)I-2.3(-9) mm wide, (4-)6-14 flowers per bract -1-2(-4) flowers per bract open at the same time, tepals subequal, 2.5-3(-3.5)mm long, and fruit 2.5-3(-3.5) mm wide. Of the species with transversely wrinkled fruits, the most similar appears to be 0. dregeanum Meisn. However, it should be stressed that although 0. dregeanum is highly polymorphic, the differences with respect to 0. annuum are consistent and absolutely clear. Specifically, 0. dregeanum is always perennial, with lanceolate-ovoid, trigonous fruits that are broadest below their middle. Nevertheless, herbarium specimens of 0. annuum are often wrongly assigned to 0. dregeanum. Of the several recognized varieties of 0. dregeanum, the most similar to 0. annuum is perhaps var. strictum (C.H. Wright) R.A. Graham, distributed throughout much of south tropical Africa, which has non-lobate leaves and generally erect pedicels, and which lacks wings or basal prickles on the fruit. However, our observations and those of Graham (1957, 1958) indicate marked differences from 0. annuum. Notably, and in addition to the differences already mentioned, 0. dregeanum var. strictum has a conspicuous, thick, woody stock, ocreae with apical fringed bristles longer than 5 mm, leaves 1-6 mm wide, and polygamous flowers. The tepal epidermis of 0. annuum has polygonal to suborbicular cells, each bearing a mammilliform-like papilla (Fig. 4). This papilla presents a randomly ridged cuticular striation, especially towards the apex. This pattern is similar to that observed in the species of Ovgonum photographed by Hong et al. (1998). Of these species, those with tepal epidermis patterns most similar to that of 0. annuum are probably 0.atripliczzolium (Meisn.) Martel and 0. stuhlmannii Dammer. ACKNOWLEDGEMENTS Our thanks go to G.V. Pope for his advice during our stay at the Royal Botanic Gardens, Kew, to Manuel Lainz for the Latin diagnoses, to Alfred0 Lopez ‘Tokio’ 17-1. zyx S. zyxwvutsrq zyxwvu zyxwv OKI'IZ /\NI).J. A. K. I"\'/\ zyxwvutsrq 6mmI D B I 3 0 0 / A I 3 cm 0 C Izyxwvutsr E lmmT lcm 0 0 I zyxwvutsrqponml Figurc 3 . Oxygonum annuum sp. nov. A, habit. B, flowcr and bract. C, ocrca and I E, fruit (all of E.A. Rotiinson 6792, K). d 13, Iwact. zyxwvutsrqp zyxwvutsrqp zyxwvu zyxwvuts zyxwvutsrqpo ligurc 4. SLAI micrograph (if tlir inner tciial rpiclrrinis crlls o f Oxygonum annuum sp. nov. (Brunimitt, <:histiinpa &k I’olliill 141 7 I , K).Scnlr bar = 10 nini. for the illustrations, to G. Norman for the English translation, and to thc kcrpcrs of the herllaria mcntioncd for the loan of study material. I76 zyxwvuts zyxwvu zyxwvuts zyx zyxw zyxwvu S.OKIIZ ANIIJ. A. K. I’AIVA Nakai T. 1926. Tadcnvi no shimburuiho. A new classification of the I h i a c a n Po!ygonnn/. Rigakukai 24(4): 289 30 I . Robyns W. 1948. Polygonaceae. In: Robyns W, cd. Flow du Congo Bdqe et du Ruanda-1 ‘rundi Vol. 1 . hlcisc: Jardin Botaniqur dc Brlgiquc, 396-427. Ronse Decraene LP, Akeroyd JR. 1988. Generic limits in Pobgonum and related genera (Polygonaceac) on the basis of floral characters. BohnicalJoumal ofthe Linnean SocL& 98: 32 I 37 I . Sojhk J. 1974. Bcmerkungen zur Gattung Tnitllurn Houtt. (Polygonaceac). Predia 4 6 I39 146. Webb DA, Chater AO. 1964. PoLygonum. In: Tutin T G el al., cds. Flora Eumpata. Cambridge: Cambridge University Press, 76 89. Wilson KL. 1988. Polygonum scnsu lato (Polygonaccae) in Australia. ?dopea 3: 177-182. Wilson KL. 1990. Some widespread species of Perszraria (Polygonacrac) and thrir allirs. hew Bullttzn 45(4):62 1-636. zyxwvu Studied mn/eria/: stkcled herbarium sptrimtns Penicaria stn‘goso (R.Br.) Nakai BOTSWANA on the Mojeye Dindinga, Smith 1321 (K; SRGH); CONGO: Haut Katanga, dt Ll.irtt 475 (BR); KENYA: Kiamlw district, Batfi\rombt 1125(K); MALAWI: Rumphi, Nyika Plateau, Chclinda Camp, Gtuwenor B Rtni 1149 (K; PRE); Mchinji Distr., Tcmbwc, banks of Bua K., on Lilongwehlchinji road, Bruniniit/ 9553 (K; PRE; SRGH); Zomba Distr., Chagwa Dam, S p n i 33 (SRGH). TANZANIA: Kwa hlshusa, Holst 91126 (BR); Usamhara, Mkuzi, Ihnnnond B Hemsley 2153 (K). ZAhtBIA: hlongu, Robinson 6867 (K; SRGH); Kasama Distr., R. Luombe, Extll, Mendonp B Wld 1370 (BM; LISC; SRGH); hlwinilunga lhtr., Milnt-Redhead 3797 (BM; K; PRE); hlkushi, Fatrshauv 1833 (K; IJSC); Chonia, 37 km from blochipapa, Astk 153.? (PRE; SRGH); ZIMBABWE: Mwami, Rand I28 (Bh,l); Rusapc, C. Dthn 1006 (K; SRGH); Chipingc, Kahanga Dam, Gibbs Ru\.\d/ 2551 (K; SKGH). Oygonutn lintare De Wild ANGOIA: Lunda, E.YP//B Aftndonp 514 (COI); idem, Ertll B Aftndonp 1455 (COI); hloxico, Go.\.\zevi/t+r 11315 (COI). CONGO: Kandale, K~udq.\t3280 (BR). 0.ygonutn dwgtanum hlcisn BOTSWANA: nrar l’scssel)r, CIUd B Dnrnnnond 6817 (K; LISC; SRGH); near Kuruman R., Burrhtll 24.59 (K). MOZAMBIQUE: h,lanica, between Ouro R. and hlacequcce, Garria 642 (LISC); idem, between RcvuC R. and Macrquecr, Barbosa 1162 (LISC); Gaza, kni 8.5 Praia S. hlartinho to hlacia, Lorrtiu B Afarque.s 1400 (LMU). SOUTH AFRICA: Natal, Port Natal, Aiau.s 283 (K); idem, Uvongo h i Hoeptn 1680 (I’RE), idm, Nrlspruit Rcscarch Station, Litbtnbq 2752 (PRE). TANZANIA: Srott-Elliot 8365 (Bhl, K). ZAMBIA: hlansa, Fansharclt 8563 (K); Scren,jr Distr., Kundalila Falls, Abmh 1646 (K); Ngoma, Xafuc Gamr Rcsenq Angus 2380 (K); 1n)magundi Distr., Alashamine, CWd B Simon 6771 (K; 1.ISC:; SRGH); Bulawayo, Kalahari sand, C;nrlpy 192 (SRGH); Harare, Ey1e.s 6940 (K; SRCH); Chirinda, Suynnerton s.n. (Bhl);Victoria, h,lakaholi Lxperiment Station, Sender& /98(PRE; SRGH). ZIMBABWE: Bulawayo, Gadntr 61 (K); blvuma-httao, hjlts 6970 (K; SRGH); Hondc Vallry, Gilliland 1169 (Bht); hl\vcnezi, brtwrcn ?’swim and Nyala, Dnrnimond 7767 (K; LISC; SRGH); Mashonaland, Ixtwccn Hararr and Headlands, Lkil 155 (K); Gweru, htlczu Agricultural School Farm, BitgeI 737 (K; SRGH); Ynymga, Biqt1 1146 (SRGH). Afog 1316 (PRE); Transvaal, Kwandelxlc, Gcmslwkfontein Farm,