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dc.contributor.advisorVenter, A. M.
dc.contributor.advisorJoubert, L.
dc.contributor.authorSidney, Nwigwe Chimdi
dc.date.accessioned2015-11-10T11:56:31Z
dc.date.available2015-11-10T11:56:31Z
dc.date.copyright2012-11
dc.date.issued2012-11
dc.date.submitted2012-11
dc.identifier.urihttp://hdl.handle.net/11660/1567
dc.description.abstractEnglish: A taxonomic revision of Finlaysonia Wall. and Streptocaulon Wight and Arn. (Apocynaceae; Periplocoideaea) in Asia is presented. This revision comprises an investigation of the nomenclature of the two genera and their species, macromorphology of all plant parts; micromorphology of leaf epidermal surfaces, seed coat surfaces and translators, pollen wall architecture, geographical distribution, habitat preferences and phylogenetic relationships. The investigation resulted in the identification of characteristics for effective delimitation of the two genera and their respective species, identification keys for both genera and the species within each genus, correction of nomenclature, determination of inter-and intra-phylogenetic relationships and determination of their distribution patterns. Available type material was investigated, type literature was confirmed for all species and synonyms were declared where applicable. Lectotypes, selected from isotypes or syntypes, were declared where holotypes were not cited by authors or were not found in their collections or were destroyed or could not be located at all. Finlaysonia and Streptocaulon are closely related genera and have many characters in common. This includes the presence of colleters on the interpetiolar ridges, in leaf axils, on the leaf petiole and main vein, in the axils of inflorescences and at the inner bases of sepals. The flowers in both genera are rather similar with bowl-shaped, inverted corolla tubes and reflexed lobes, presence of only the primary corona which is divided into a foot and lobe, presence of interstaminal nectaries, translators and pollinia, two semi-inferior, apocarpous many ovuled-ovaries, a compound style, a gynostegium that is the result of fusion between stylar head and anthers, paired follicles and seeds with comas at the micropylar end except in F. obovata where the coma is replaced by a winged, fimbriate margin. Finlaysonia is characterized by trichomes on the outer or inner surfaces of the corolla, presence of anther callosities except in F. pierrei. Streptocaulon, in contrast, is characterized by a glabrous corolla, absence of anther callosities. A number of characters, unique to a specific species and thus diagnostic were used in identifying of the species. Vegetative features provide the most effective means to distinguish and identify the species and combinations of leaf shape, leaf length:width ratios, texture, leaf indumentum and petiole length proved to be taxonomically the most valuable characters. Corolla lobe apex shape, corona lobe shape, anther connective indumentum, style indumentum, follicle and seed shape and size, seed margin appearance and coma length and presence/absence of coma are diagnostically useful. Micromorphological features of the leaf epidermis, such as primary sculpture, as well as stomata characteristics and distribution can also be useful. However, a single character is often insufficient to distinguish between the genera and a combination of characters should to be applied. Finlaysonia and Streptocaulon are widely distributed in Asia with the largest concentration of species in Thailand. Species like F. khasiana, F. obovata, F. pierrei, S. juventas and S. wallichii are common, while F. decidua, F. puberulum, F. venosa, F. insularum, S. cumingii, S, curtisii, S. lanuginosa and S. sylvestre have restricted distributions, at present only known from one or two localities. Most of the species are found on limestone and form part of scrub forest and mixed deciduous forest. Finlaysonia obovata typically are found in mangrove forests along coastal lagunes and tidal rivers, while S. sylvestre and S. juventas are found in riverine forest along fresh water rivers. The phylogenetic treatment was based on morphological characters of vegetative parts, flowers and fruits. The analyses yielded polytomies as strict concensus trees unless the Bootstrap support values were ignored. However, an exciting result from the strict concensus trees was the pairing of S. lanuginosa and S. curtisii in a clade, confirming the finding of Ionta and Judd (2007) and justifying the transfer of these two species from Finlaysonia to Streptocaulon.en_ZA
dc.description.abstractAfrikaans: ‘n Taksonomiese hersiening van Finlaysonia Wall. en Streptocaulon Wight & Arn.(Apocynaceae; Periplocoideae) in Asië word aangebied. Hierdie hersiening behels ‘n ondersoek van die nomenklatuur van die twee genera en hulle spesies, makromorfologie van alle plantdele; mikromorfologie van blaarepidermis- en saadhuidoppervlakke en translators, stuifmeelwandargitektuur, geografiese verspreiding, habitatsvoorkeure en filogenetiese verwantskappe. Die ondersoek het gelei tot die aanwysing van kenmerke vir doeltreffende omgrensing van die twee genera en hulle onderskeie spesies, opstel van identifiseringsleutels vir die twee genera en hulle afsonderlike spesies, regstelling van nomenklatuur, bepaling van inter- en intrafilogenetiese verwantskappe en die vasstelling van geografiese verspreidingspatrone. Beskikbare tipemateriaal is ondersoek, tipeliteratuur is vir al die spesies bevestig en sinonieme is, waar van toepassing, aangedui. Waar holotipes nie deur outeurs aangewys is nie, of nie in hul versamelings gevind is nie, of vernietig is, of geensins opgespoor kon word nie, is lektotipes uit isotipes of sintipes aangewys. FInlaysonia en Streptocaulon is naverwant en het verskeie kenmerke in gemeen. Dit sluit in die voorkoms van kolleters op die interpetiolêre riwwe, in die blaaroksels, op die blaarsteel en hoofaar, in die oksels van bloeiwyses en by die binnebasis van kelkblare. Daar is ‘n sterk ooreenkoms tussen die blomme van die twee genera, met bakvormige, omgebuigde kroonbuise en teruggebuigde kroonlobbe, teenwoordigheid van slegs die primêre bykroon wat verdeel is in ‘n voet en lob, die teenwoordigheid van nektarkliere tussen die meeldrade, translators en polliniums, twee halfonderstandige, onvergroeide vrugbeginsels met baie sade, ‘n saamgestelde styl, ginostegium gevorm uit die vergroeiing van stylkop en meeldrade, gepaarde kokervrugte en sade met vrugpluise aan die saadpoortjie se kant. Finlaysonia obovata is die uitsondering waar die saadpluis deur ‘n vlerk en rand met kort haartjies vervang is. Finlaysonia word gekenmerk deur hare aan die buite- of binnekant van die kroon, teenwoordigheid van bolvormige uitwasse of “kallosiete” aan helmknopbasisse, behalwe in F. pierrei. Streptocaulon, daarenteen, word deur ‘n haarlose kroon, afwesigheid van helmknopkallosiete. ‘n Aantal kenmerke wat uniek aan ‘n bepaalde spesies is en dus van diagnostiese waarde is, is vir uitkenning van die soorte benut. Vegetatiewe kenmerke werk die beste, en kombinasies van blaarvorm, verhouding van blaarlengte:breedte, tekstuur, blaarbeharing en blaarsteellengte is as die taksonomies waardevolste kenmerke vasgestel. Vorm van kroonlobpunte, bykroonlobvorm, helmbindselbeharing, stylbeharing, kokervrug- en saadvorm en –grootte, saadrandvoorkoms en lengte van die saadpluis of teenwoordigheid of afwesigheid daarvan besit diagnostiese waarde. Mikromorfologiese kenmerke van blaarepidermisse, soos primêre struktuur, asook huidmondjiestruktuur en -verspreiding kan diagnosties ook nuttig gebruik word. ‘n Enkele kenmerk is nie genoegsaam om tussen die genera te onderskei nie, maar verskeie kenmerke moet saam gebruik word. Finlaysonia en Streptocaulon is wyd oor Asië versprei met die grootste konsentrasie van spesies in Thailand. Spesies soos F. khasiana, F obovata, F. pierrei, S. juventas en S. wallichii kom wyd versprei voor, terwyl F. decidua, F. puberulum, F. venosa, F. insularum, S. cumingii, S. curtisii, S. lanuginosa en S. sylvestre beperkte verspreidings het en tans van slegs enkele lokaliteite bekend is. Die meerderheid spesies groei op kalksteen en maak deel uit van struikwoud of gemengde bladwisselende woud. Finlaysonia obovate kom tipies in manglietwoude langs kusmere en getyriviere voor, terwyl S. sylvestre en S. juventas in oewerwoude langs varswaterriviere aangetref word. Slegs morfologiese kenmerke van vegetatiewe dele, blomme en vrugte is in die filogenetiese studie gebruik. Daar is geen resolusie in die streng konsensus bome gevind nie, tensy die skommelskuif-ondersteuningswaardes of “bootstrap support values” weggelaat is. ‘n Belangrike resultaat is met die filogenetiese ondersoek verkry, naamlik dat S. lanuginosa en S. curtisii telkens in dieselfde klade gegroepeer het, wat die bevinding van Ionta en Judd (2007) bevestig en die oordrag vanaf Finlaysonia na Streptocaulon regverdig. Al die kladogramme dui aan dat die oorblywende Finlaysonia spesies nie saam hoort nie, maar waarskynlik in die oorspronklike drie genera, Finlaysonia, Meladerma en Atherolepis terug geplaas moet word.af
dc.description.sponsorshipThe Department of Plant Sciences, University of the Free Stateen_ZA
dc.language.isoenen_ZA
dc.publisherUniversity of the Free Stateen_ZA
dc.subjectTaxonomyen_ZA
dc.subjectPlants -- Classificationen_ZA
dc.subjectFinlaysoniaen_ZA
dc.subjectPeriplocoideaeen_ZA
dc.subjectAsian floraen_ZA
dc.subjectApocynaceaeen_ZA
dc.subjectStreptocaulonen_ZA
dc.subjectDissertation (M.Sc. (Plant Sciences, Botany))--University of the Free State, 2012en_ZA
dc.titleA of finlaysonia and streptocaulon (periplocoideae; apocynaceae)taxonomic revisionen_ZA
dc.typeDissertationen_ZA
dc.rights.holderUniversity of the Free Stateen_ZA


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