A TAXONOMICSTUDY OF THEGENUS XIMENIA IN NAMIBIA MARIANNEM. UIRAS NationalBotanical Research Institute, Private Bag 13184, Windhoek, Namibia ABSTRACT MATERIALSAND METHODS The genusXimenia, with two speciesoccurring in Namibia, A literaturesurvey was undertaken.Alllhe Ximenla specimens wasthe subject of a taxonomicstudy at theNational Herbarium in the NationalHerbarium of Namibiawere studied.Different (Radfor,1974; of Namibia.Recent taxonomic revisions elsewhere have morphologicalcharacters were lookedat delimitedtwo new varietiesfor Namibia.Existing descriptions Samuel,1937) and compared and data analysed for characters peduncle, Tables and keys for Ximeniain Namibiawere thereforereviewed and of leaves,inflorescence, bark, sepalsand fruit. with differentcharacters were drawnup. Approximately 25-30 updated. "Windowleen" soecimenswere used. Flowers were soaked in Theresults were that an updatedand comprehensive literature for 10-15minutes, dissected and compared.To accountfor dossieron the genus in Namibiawas compiled,and the intra-specificvariation 5-10 specimensof each species Namibiantaxa within the genusXimeniawere documented and (dependingon the availablespecimens with flowers)were a keywas compiled. included.These characters were studied under a microscope. Drawingsof floweringbranches and flowerswere made from the soecimensand dissectedflowers. INTRODUCTION Labeldata from each specimen were loaded on thespecialised Thegenus Ximenla L. (familyOlacaceae) is composedof eight computerprogramme called the SpecimenDatabase, and maps speciesof thornyshrubs and trees. Six of the species(X. weredrawn. The specimens, which were incorrectly identified, coriacea Engler,X. horrida Urban & Ekman, X. intermedia wereredetermined. (Chodat& Hassler)DeFiliipps, X. parvifloraBentham, X. pubescensStandley and X. roigiiLeon.) occur throughoutAfrica The key was constructedbased on the specimensstudied. lt and two species (X. americanaL. and X. caffra Sond') are was testedin the NationalHerbarium in orderto determine four foundin Namibia(Craven, 1999). The botanicalname Ximenia applicabilityand appears to workwell for distinguishing the was derivedform a Spanishmonk, Francisco Ximenez, who Namibiantaxa. wroteabout plants of Mexicoin the 17thcentury (Craven, 1989). This genuswas first describedby Linnaeusin Species Plantarumin 1753.Since then it hasbeen recorded in a number TAXONOMY of Floras such as Prodromus einer Flora van Sadwestafrika (1967),Flora de Mozambique(1979), Flora of TropicalEast Ximenia L. Africa (1968) and FloraZambesiaca (1963). a. Branchesand leaves glabrous or glaucous.Leaves folded It was confirmedthat the two speciesoccurring in Namibiaare alongthe canaliculatemidrib. Flowers borne on facultativehemiparasites (DeFilipps, 1969) which may liveon pedunculatecymes or umbels,sometimes solitary. Sepals the roots of availablehost plantsgrowing nearby, as well as andpedicels glabrous....... ...-..X. americana autoparasitesthat attachto non-livingobjects like stone and plastic. b. Branchesand leavesvillous or coriaceous.Flowers pedicellatein fasciclesor solitary,appear in clusters pedicels This plantis of economicimportance, having both nutritional on lateral shoots. Sepals and villous or and medicinalvalue. The leavescan be driedand crushedto tomentose .................X.caffra makepowder to breakfever. They are alsoused as a substitute (1753) for spinachand eatenby animalssuch as giraffe.An infusion 1. Ximeniaamericana 1., Sp. Pl. : 1193 made from the root is used as remedyfor dysenteryand (20-)30-40 diarrhoeaand abdominalpain, mentalillness, fever and a. Leaves glabrousbut not glaucous;lamina bilharzia.Powder is alsoapplied to sores.The fruits are eaten (-50) x (10-)15-20(-30)mm; apex retusewith mucro. raw and seeds are crushedfor extractionof the oil, which is Inflorescenceumbel, cyme. Pedicelebracteate, calyx mixedwith redochre for cosmeticuse on skinand hair.Roasted ci1iate............ ...var.americana and poundedseeds are used forwounds (Rodin, 1985; Leger, 1997). AGRICOLA2OOl 111 b. Leavessmall, glabrous and glaucous;lamina (15-)20-25 Diagnosticfeatures (-35) x (6-)12-15(-20)mm, usually folded along the midrib:aoex retusewith or withoutmucro. Inflorescence Smallglabrous and glaucousleaves which are usuallyfolded umbel or solitary cyme. Pedicel bracteatenear the alongthe midrib.Cyme sometimesone-flowered, bracteate midd1e........... .var.microphylla nearthe middle. Pedicel bracteate where it joins the peduncle. Sepalseciliate. Style sometimes absent to/or 0,5 mm. 1.1 Ximenia americana l. var. americana Flowering Type:Tropical America, Hort. Cliff. 483 (BM,lecto) Floweringoccurs throughoutthe year accordingto the Previousillustrations: Garcia: 33 (1963);Lucas: 4 (1968) specimensin theherbarium. Diagnosticfeatures Distributionand habitatpreference Leavesand branchesglabrous. Inflorescence cyme or umbel. This taxon has a wide range of distributionin the northern Pedicelsebracteate. Sepals ciliate. Flowers pedunculate. regionsof Namibia,where it often overlapswith the other varieties.lt isfound in various habitats and latitudes. but mostlv Flowering in softloamy sand, and deepsands. Plantsflower throughout the year, according to the specimens 2. Ximenia carTraSond. in theherbarium. The literaturedescribed the flowering season from Septemberto December(Berry, 1974). Youngbranches and leavesvillous or tomentose,leaves conspicuouslydark to shinygreen adaxially. Sepals and Distributionand habitatpreference oedicelvillous ortomentose............. ..var.caffra Thisvariety occurs in the northernregions of Namibia,mostly b. Young branchesand leavesglabrous but coriaceous, theOmusati, Ohangwena, Erongo and Okavango Regions. The leavesdull brown to green. Petiolevillous in adaxial plantshave no preferencefor a specifichabitat, but can grow groove var. natalensls in a widerange of habitats. 2 .1 Ximenia calTraSond. var. caffra 1.2 Ximenia americana L. var. microphylla Welw.ex Oliv. Type:SATransvaal, Magaliesberg, Zeyher 1847 (K, iso) Type:Angola, Welwitsch 1127 (K, holo) Previousillustrations: Garcia: 33 (1963);Lucas: 4 (1968) Previousillustration: Craven: 111 (1989) b) d) Z-N f 8;) N*--z2 Figure1 . Ximeniaamericana var. americana: a) floweringbranch, b) leafadaxial view, c) verticalsection of the flower,x10, d) floraldiagram (all four varietieshave similar floral arrangement). 112 AGRICOLA2OO1 tr) Figure2. Ximenia americana var. microphylla: a)flowering branched b) leaf,adaxial view, c) verticalsection of theflower. Diagnosticfeatures 2.2 Ximenia caffra var.nafalensis Sond. Leavesand branchesvillous to tomentose.Inflorescence with pedicellateflowers in umbels.Sepals and pedicelvillous. Type:SA, Natal, Durban (Port Natal), Gueinzius 79 (MEL,holo) Flowering Diagnosticfeatures The floweringperiod is recordedin the literatureas from Petiolewith hair in the adaxialchannel. Leaves coriaceous. '1963). Septemberto March(Garcia, Accordingto herbarium Flowerswith long pedicels. specimens,this taxon flowers throughout the yearin Namibia. Flowering Distributionand habitatpreference No specimensof thisvariety had flowers and thereforeit was Plantsare distributedall overthe northernregions where the not possibleto determinethe phenology. rainfallis higher. b) e) g -f' $' ,rry # L' -.ii-- Figure3. Ximeniacaffra var. caffra: a) floweringbranch, b) leaf,adaxial view, c) verticalsection of the flower,x10, d) hairtype hirsuteadaxial e) hair type hirsuteabaxial AGRICOLA2OOl 113 h) L. l Figure4. Ximeniacaffravar. natalensis:a) floweringbranch, b) leaf,adaxial view, c) crosssection of the leaf,x10 Distributionand habitatpreference someauthors regard them as synonymsof eachother, e.g. X. americanavar. microphvlla= X. americanavar. americana Thistaxon is widespread in the Oshikoto, Ohangwena, Kunene, (Lucas,1968). Okavangoand ErongoRegions. lt generallyprefers woodland, bushlandand grasslandsand growsin soft soilsand also in Therewas no fieldworkdone to see the plantsin theirnatural stonyareas. habitatand to collectfresh specimens. Therefore,only specimensin the herbariumwere used in this study.The problemfound during the study was thatX. caffravar. nafalensls DISCUSSION was under-collectedand, due to the lack of fertilematerial, onlythe leaveswere studied. A cleardifference could be seen The aim of the studywas to makea cleardistinction between in the leavesof all the taxa studied.Further differences were the soeciesof Ximeniain Namibia.The taxaare describedin observed,such as that X caffra var. natalensishave fewer variousarticles, but these descriptions for Namibiantaxa were spines and longer pedicelsthan X. caffra var. caffra, which not compiledin a single,user-friendly publication. The study verifiedfindings in the literature.(Milne-Redhead, 1936). was aimedto eliminateconfusion among the taxa, because =ri . L-Ll .! @ - : : ";r'-'tll r,.i l \-l i'l.l lI--,1tl. r , l l I I \ I ii i 24 il l il \ \ \l 'tl r Lrr i, i it 26-.1 tttl t:\: (:tr lh€ne cri€ sond !{ cilne 1 l-'tl t, jtr{ \ f f \ - \r r '. 12 14 16 18 18 Figure5 and 6. The geographicaldistribution of thefour varieties of Ximeniain Namibia. 114 AGRICOLA2OO1 It is clear from the maps that distributionsof the differenttaxa and has been prioritisedby the NBRI for further investigation. overlapand thereforevarieties, and not subspecies,exist. There Baseline studies of this type are essential prior to meeting is a limitationin the range of X. caffravar. natalensiswhile var. nationalobjectives of development and food-security. caffra occurs over a vast area (Figure 5 and 6). Skills in taxonomic researchhave