bluuebunny/crossref_metadata_2025_split huggingface dataset:
The morphology and systematic position of the Didiereaceae of Madagascar
Authors: Rauh W. 
Published: July 2015

The Didiereaceae, endemic to the arid south-west of Madagascar is one of the most remarkable plant families in the world. Four genera and 11 species are known, of which 3 have been described by the author: Decaryia (1 species), Alluaudiopsis (2 spp.), Alluaudia (6 spp.) and Didierea (2 spp.). The species show different growth forms, but their shoot-stem-systems are basically similar; they are all spiny, semi-succulent deciduous shrubs or trees, with a stem (shoot) system differentiated into long-shoots and short-shoots (brachyblasts). The long shoots bear normal leaflets, which soon fall off. In their axils, brachyblasts develop proleptically, which produce two types of leaves (1) thorns which develop proleptically in different numbers (1 in Alluaudia, 2 in Alluaudiopsis marnieriana and several Didierea)-, (2) leaves which are green, deciduous assimilation organs (2 per brachyblast in Alluaudia, several in Didierea). The stem organization is comparable to that of the Cactaceae of the New World. The brachyblasts of the Didiereaceae are homologous to the areoles of the Cactaceae, most obviously to those of the primitive members, the Pereskioideae. The affinities between the two families can be demonstrated by means of grafting. It is possible to graft Didiereas onto Pereskioideae and vice versa. The flower structure of Didiereaceae is very uniform. Flowers are unisexual and dioecious and show affinities to those of the Portulacaceae. The development of the gynoecium, the ovule and the female gametophyte as well as the presence of betalains in the flowers indicate that the Didiereaceae do not belong to the Sapindales as was sometimes assumed, but to the Centrospermae. They should be placed between Portulacaceae and Cactaceae. The ancestors of the Didiereaceae are not known.
Sporoderm morphogenesis in <i>Euphorbia obesa</i> and <i>Croton gratissimus</i>
Authors: Frean M. L. 
Published: July 2015

Pollen grains of the Euphorbiaceae show a number of pollen types which can be clearly distinguished. Generally different genera are characterized by a specific pollen type. Euphorbia obesa Hook. f. and Croton gratissimus Burch, subsp. subgratissimus (Prain) Burtt Davy, represent two genera within the Crotonoideae with different morphology, each type characteristic for the respective genus. Taxonomically, the genus Euphorbia with apetalous flowers consisting of a naked pistil surrounded by several staminate flowers within a cyathium, is considered more advanced than the genus Croton. In Croton the inflorescence is a raceme with unisexual flowers. The floral whorls of the male show numerous anthers and both calyx and a showy corolla are present. Both genera are insect pollinated. In both Euphorbia obesa and Croton gratissimus the pollen wall in section shows columellae, a structure characteristic of angiosperms. However the present ontogenetic studies show that the formation of the columellae differs entirely in the two pollen types. The final stratification of the wall as well as the morphology of the grains differ and evaluation of the exine structure indicates that phylogenetically Croton pollen shows more advanced characters than Euphorbia — contradicting the floral phylogeny. This study conducted at light and electron microscope level compares the two pollen types morphologically and ontogenetically, concentrating mainly on the formation of the exine which is tectate-perforate in the prolate tricolpate grain of Euphorbia obesa and semi-tectate in the anaperturate, spheroidal grain of Croton gratissimus. The aim of the study was to evaluate the significance of pollen characters in taxonomic and phylogenetic relationships within the Euphorbiaceae. The differing pollen morphology which is related to the taxonomic grouping of tribes within the subfamily (Crotonoideae) emphasizes diversity, which may result from physiological adaptation. The study shows that the same functional end may well be achieved in different ways and this may be a factor underlying the diversity in the heterogeneous family Euphorbiaceae.
Ten interesting species of aquatic Hyphomycetes from South Africa
Authors: Sinclair R. C. , Eicker A. 
Published: July 2015

Examination of the foam spora of South Africa has revealed the presence of ten interesting species from nine genera, seven of which are new records for the African continent and three for South Africa. These are Anguillospora crassa Ingold, Condylospora spumigena Nawawi, Flabellospora verticillata Alasoadura, Lateriramulosa uni-inflata Matsushima, Lemonniera alabamensis Sinclair Morgan-Jones, Lemonniera filiformis Petersen ex Dyko, Lunulospora cymbiformis Miura, Speiropsis irregularis Petersen, Tetrachaetum elegans Ingold and Tricellula aquatica Webster.
Alien trees, shrubs and creepers invading indigenous vegetation in the Hluhluwe-Umfolozi Game Reserve Complex in Natal
Authors: Macdonald I. A. W. 
Published: July 2015

The results of a survey and monitoring programme conducted in the Hluhluwe-Umfolozi Game Reserve Complex in Natal are presented. The area consists of 900 km2 of savanna and forest vegetation. Twenty alien tree, shrub and creeper species currently invading indigenous vegetation within the Complex are listed. Herbaceous aliens were not surveyed. An analysis of the habitats being invaded by these alien plants is presented and it is concluded that riverine and forest-edge habitats are those most seriously threatened by alien plant infestations. The distribution, nature and history of the infestations of each species are summarized. Distribution maps given for the eight species which are currently most important in the Complex. The potential threat posed by each species is estimated and the species are ranked in order of priority for control action. The South American composite, Chromolaena (Eupatorium) odorata, is identified as being the alien species currently posing the greatest threat to natural vegetation in the Complex. The Asian tree, Melia azedarach, is considered the second most important alien species invading the area. It is concluded that both these species should be declared noxious weeds throughout the Republic and that research into their biological control is urgently required.
Weed flora of South Africa 2: power shifts in the veld
Authors: Wells M. J. , Engelbregcht V. M. , Balsinhas A. A. , Stirton C. H. 
Published: July 2015

This paper, the second in a series analysing data from the National Weed List, concentrates on weedy changes that affect the indigenous flora. The incidence of weediness and of threatened species is used as an indication of success or failure of families under prevailing conditions of disturbance. The resulting power shifts between indigenous families and the impact of exotic weeds on the situation are reviewed. Many power shifts are taking place between indigenous species in the veld. Superficially it seems as though a relatively few invasive species are displacing a larger number of threatened species, but evidence from Natal points to more species increasing than decreasing under conditions of over-utilization. Amongst small families power shifts are almost as prevalent and important as at species level. Seventeen small families have over 20% indigenous weed species. Thirty small families have over 20% threatened species, and 21 small families have had their species numbers bolstered by more than 20% by exotic weeds. A very few large and medium-sized families contain over 50% of our weeds and our threatened species. It is mostly temperate (Cape) families that are under pressure relative to more tropical families. This trend is echoed at sub-family level within the Fabaceae.
The genus <i>Tetradenia</i> Benth. (Lamiaceae). 11. Malagasy Republic
Authors: Codd L. E. 
Published: July 2015

Three species of Tetradenia are recognized in the Malagasy Republic: T. fruticosa Benth.. T. goudotii Briq. (= T. hildebrandtii Briq.) and the newly described T. nervosa Codd.
Revision of the genus <i>Myrsiphyllum</i> Willd.
Authors: Obermeyer A. A. 
Published: July 2015

The genus Myrsiphyllum Willd. (Liliaceae—Asparageae) is revised. Twelve species are recognized, one of which is new. namely, M. alopecurum Oberm. Eight new combinations are made. A key is provided for distinguishing Myrsiphyllum from Protasparagus Oberm.
A vegetation survey of the Cape of Good Hope Nature Reserve. I. The use of association-analysis and Braun-Blanquet methods*
Authors: Taylor H. C. 
Published: July 2015

The survey aimed to establish broad vegetation units that could be mapped on an extensive scale in the Cape of Good Hope Nature Reserve at the southern tip of the Cape Peninsula. This paper compares the performance of two methods, association-analysis and the Braun-Blanquet method as developed by the Zurich-Montpellier School of Phytosociology. One hundred 50 m2 sample plots, covering the whole Reserve, were placed systematically at grid intersections on the 1:18 000 topographical map. at 1 000-yard (914 m) intervals. Species lists, recording merely presence of all species with permanently recognizable aerial parts, were made for each plot. The association-analysis resulted in a classification of 23 final groups of sample plots, of which only five groups showed high floristic and ecological homogeneity. Of the remainder, eight groups contained some anomalous, misplaced plots, and ten represented small, isolated fragments of natural units. The original data were then analysed using Braun-Blanquet methods to provide an independent classification for comparison with the former. The Braun-Blanquet communities were found to be more homogeneous in terms of previously defined habitat groupings and showed floristic relationships consistent with these groupings. It is concluded that, with the type of sampling used, the synthetic phytosociological Braun-Blanquet method provides a more natural classification of plant communities of the Reserve than does the monothetic divisive association-analysis method.
New species and combinations in <i>Parmelia</i> (Lichenes) from southern Africa F. BRUSSE*
Authors: Brusse F. 
Published: July 2015

Eight new species are described and six new combinations are made in the lichen genus Parmelia from southern Africa, The new species are Parmelia astricta Brusse, P. clivorum Brusse, P. marroninipuocta Brusse, P. patula Brusse, P. scitula Brusse, P. sparengs en s Brusse, P. unctula Brusse and P. veroicosa Brusse. The new combinations are P. ag g reg a ta (D. Knox) Brusse, P. c ed rus-montana (Brusse), Brusse, P. dysprosa (Brusse D. Knox) Brusse, P. exornata (Zahibr.) Brusse, P. karoo (D. Knox Brusse) Brusse and P. leucostigma (Brusse) Brusse.
The genus Scleria in southern Africa
Authors: Hennessy E. F. Franklin 
Published: July 2015

The 23 species of Scleria (Sclerieae, Caricoidcae, Cyperaceae) in southern Africa are revised. Two subgenera are recognized, Hypoporum with one section, Hypoporum, and Scleria with three sections. Scleria, Acriulus and Schizolepis. The tribes Sclerieae and Bisboeckelereae are distinguished.
Leaf anatomy of the South African Danthonieae (Poaceae). X. <i>Pseudo- pentameris</i>
Authors: Ellis R. P. 
Published: July 2015

The leaf blade anatomy of Pseudopentameris macramha (Schrad.) Conert and P. brachyphylla (Stapf) Conert was studied both in transection and in surface view and is illustrated by means of photomicrographs. The leaf anatomy is typically danthonoid. T he abaxial epidermis consists of inflated, hexagonal long cells and stomata and micro-hairs are absent. Adaxial micro-hairs were observed. The creation of a new genus to accommodate these two species appears justified but certain species in Pentameris Beauv., Merxmuellera Conert and Pentaschistis Stapf show similarities to Pseudopentameris and consideration should be given to their inclusion in Pseudopentamem.
Leaf anatomy of the South African Danthonieae (Poaceae). XII. <i>Pentameris thuarii</i>
Authors: Ellis R. P. 
Published: July 2015

The leaf blade anatomy of Pentameris thuarii Beauv. is described and illustrated. It is shown that the leaf anatomy of P. thuarii bears little resemblance to the anatomy of P. macrocatyciiw (Steud.) Schweick.. P. obiiisifolia (Hochst.) Schweick., P. longiglumis (Nccs) Stapf or P. dregeana Stapf. The leaf anatomy of P. thuarii was found to correspond closely with that of some specimens of Pentaschistis pallescens (Schrad.) Stapf, P. silvatica Adamson and P. lonuosa (Trin.) Stapf. The morphology of these Pentaschistis specimens needs to be compared with that of P. thuarii in order to establish whether the true relationships of P. thuarii lie with these taxa. Anatomically. P. thuarii does not appear to be closelv related to anv species presently classified in Pentameris.
The identity of <i>Erica vinacea</i> and notes on hybridization in Erica
Authors: Oliver E. G. H. 
Published: July 2015

The rediscovery of Erica vinacea L. Bol. among sympatric populations of two other species led to a comparison of their morphological characters. Results of this study indicate a putative hybrid origin: E. x vinacea L. Bol. = E. fastigiata L. x E. fervida L. Bol.
E. A. C. L. E. (Ted) Scheipe (1924-1985) — a biography
Authors: Oliver E. G. H. 
Published: July 2015

Prof. E.A.C.L.E. Scheipe was born in Durban on 27 July 1924 and died in Cape Town on 12 October 1985. He studied at the University of Natal and at Oxford, England. He was awarded an M.Sc. (S. Afr.) for a thesis on the ecology of the Natal Drakensberg and a D. Phil. (Oxon.) for a thesis on the ecology of bryophytes. For a brief period he was Curator of the Fielding Herbarium, Oxford. In 1953 he was appointed Lecturer in Botany at the University of Cape Town, until in 1973 he was awarded a full professorship (ad hominem) and the title of Director of the Bolus Herbarium. Here he established a school of taxonomy and promoted 22 theses. His main fields of research were the taxonomy and phytogeography of Pteridophyta (especially African groups) and of Orchidaceae.He has 112 publications to his credit and collected over 7 000 numbers in various regions of Africa, in Europe and the Himalayas. He was a keen gardener and was active in several societies promoting horticulture, orchidology and nature conservation. He was a member of several scientific committees and was repeatedly honoured for his work.Three children were born from his marriage to Sybella Gray, also a botanist.
The taxonomy, chorology and reproductive biology of southern Afri­can Meliaceae and Ptaeroxylaceae
Authors: White F. 
Published: July 2015

Information is provided on the taxonomy, chorology and reproductive biology of 14 indigenous and two introduced species of Meliaceae in southern Africa, and on Ptaeroxylon (Ptaeroxylaceae). Two new taxa are described: Nymanieae F. White, tribus nov. and Turraea strevi F. White B. T. Styles, sp. nov. Nurmonia (Harms) F. White, comb, et stat. nov.. a new section of Turraea L. is created. The account complements the treatments of these families in the Flora of southern Africa.
Studies in the genus <i>Riccia</i> (Marchantiales) from southern Africa. 4. Three endemic species, <i>R. natalensis</i>, <i>R. microciliata</i> sp. nov. and <i>R. mammifera</i> sp. nov.
Authors: Volk O. H. , Perold S. M. 
Published: July 2015

Three endemic species of the group 'Ciliatae' (subgenus Riccia sectio Riccia) are dealt with. The description of R. natalensis Sim is emended, as Sim's original description (1926) was sketchy and Arnell (1963) had no fresh material to examine, which resulted in some inaccurate observations: R. microciliata Volk Perold is a diminutive new species w'ith conspicuous, arched marginal and occasionally dorsal cilia, whereas R. mammifera Volk Per­old. another new species, has enlarged cells (or short cilia) along the thallus margins.
Leaf anatomy of the South African Danthonieae (Poaceae). XIV. <i>Pentameris dregeana</i>
Authors: Ellis R. P. 
Published: July 2015

Transverse sections and abaxial epidermal scrapes of leaf blades of Pentameris dregeana Stapf, both of herbarium specimens and of freshly fixed material, were examined by light microscopy. The anatomical structure was found to be basically uniform in a representative sample. A few somewhat atypical specimens, how'ever, showed epidermal similarities with Pentaschistis colorata (Steud.) Stapf. A comparison with other danthonoid grasses revealed some specimens identified as Pentaschistis colorata var. polytricha Stapf which resemble Pentameris dregeana very closely in leaf anatomy. A definite gradation in leaf anatomy between Pentameris dregeana and Penta­schistis colorata appears to exist and. consequently, it is proposed that the affinities of Pentameris dregeana lie with this group of Pentaschistis species rather than close to any of the other Pentameris species.
Two new brown subcrustose <i>Parmelia</i> species from southern Africa (lichenized Ascomycetes)
Authors: Brusse F. 
Published: July 2015

Two new brown subcrustose species of Parmelia (Lichenes) are described from southern Africa on rock. They are P. barda Brusse and P. princeps Brusse. The affinities of the two species are discussed.
<i>Cetraria</i> (Parmeliaceae) and some related genera on the African continent
Authors: Kärnefelt I. 
Published: July 2015

Four species are reported new for the lichen flora of southern Africa: Bryoria fuseescens (Gyeln.) Brodo D. Hawksw., B. motykae (D. Hawksw.) Brodo D. Hawksw., Cetraria chlorophylla (Humb.) Vain, and Platismatia glauca (L.) Culb. Culb. (Parmeliaceae), found at high elevations in Natal and south-west Cape. B. fuscescens, B. motykae and P. glauca were previously known from a few localities, also at high elevations, in east Africa. The genus Cetraria s. str. was previously unknown on the African continent.
Taxonomy of the genus <i>Ehrharta</i> (Poaceae) in southern Africa: the Setacea group
Authors: Gibbs Russell G. E. 
Published: July 2015

The Setacea species group in the genus Ehrharta Thunb. is differentiated morphologically by the short first sterile lemma and by inflorescences of fewer than 20 spikelets. The Setacea group is composed of two species, each with subspecies linked by intraspecific intermediates: E. rupestris Nees ex Trin. subsp. rupestris; subsp. tricostata (Stapf) Gibbs Russell; subsp. dodii (Stapf) Gibbs Russell and E. setacea Nees subsp. setacea; subsp. scabra (Stapf) Gibbs Russell; subsp. uniflora (Burch, ex Stapf) Gibbs Russell; subsp. disticha Gibbs Russell. All taxa are endemic to the Fynbos vegetation of the south-western Cape Province, with distribution centred in the Caledon degree grid (3419). Parallel trends for plant size and habit, leaf blade width and position, and spikelet size are demonstrated in both species, with similar plant types occurring in similar geographical areas.
Leaf anatomy of the genus <i>Ehrharta</i> (Poaceae) in southern Africa: the Setacea group
Authors: Ellis R. P. 
Published: July 2015

The leaf blade anatomy of the taxa of the Setacea group of species of the genus Ehrharta is described and illustrated. This group includes E. rupestris Nees ex Trin. subsp. rupestris, subsp. tricostata (Stapf) Gibbs Russell and subsp. dodii (Stapf) Gibbs Russell, as well as E. setacea Nees subsp. setacea, subsp. scabra (Stapf) Gibbs Russell, subsp. uniflora (Burch, ex Stapf) Gibbs Russell and subsp. disticha Gibbs Russell. All these taxa share a very characteristic leaf anatomy with inrolled or infolded leaves without keels and have adaxial ribs with interlocking prickles. The chlorenchyma is dense and compact with inwardly projecting invaginations visible in all taxa except E. setacea subsp. setacea. In E . setacea subsp. scabra typical arm cells are present. Abaxial costal and intercostal zones are not differentiated and stomata are absent. The long cells are hexagonal or inflated with sinuous walls. Silica bodies are single or paired and rounded in shape. Small hook-like prickles with short barbs are common. Microhairs with a short, truncated distal cell occur. This leaf anatomical structure differs considerably from that of the other species groups recognized in African Ehrharta and the Setacea group appears to be more distinct from the other groups than they are from each other.
The genus Rubus (Rosaceae) in South Africa. IV. Natural hybridiza­ tion
Authors: Spies J. J. , Stirton C. H. , Du Plessis H. 
Published: July 2015

The genus Rubus L. is represented in southern Africa by the subgenera Eubatus Focke and Idaeobatus Focke. A combination o f morphological data, data on the reproductive systems of some collections and meiotic chromosome behaviour indicates that a hybrid swarm in the eastern Transvaal was formed subsequent to the hybridization between R. cuneifolius Pursh. taxon B (subgenus Eubatus) and R. longepedicellatus (C. E. Gust.) C. H. Stirton (subgenus Idaeobatus). Other examples of intra- and intersubgeneric hybridization were found during this study of the South African material. These instances, with examples found in the literature, indicate that the subgeneric subdivisions of Rubus are artificial. Three different methods were used to analyse the meiotic chromosome configurations. The genome relationship system of Alonso Kimber (1981) and Kimber Alonso (1981) and the modification of the binomial system of Jackson Casey (1980) by Spies (1984) proved to be the most sensitive for distinguishing between alio-, segmental alio- and autoploids.
Taxonomy of the genus <i>Ehrharta</i> (Poaceae) in southern Africa: the Villosa group
Authors: Gibbs Russell G. E. 
Published: July 2015

The Villosa species group in the genus Ehrharta Thunb. is differentiated morphologically by very large, profusely hairy, bearded and aristate spikelets and by a suffrutescent habit, with culms woody at the base and with reduced leaf blades. The Villosa group is composed of two species, one with a variety: E. thunbergii Gibbs Russell, nom. nov., E. villosa Schult. f. var. villosa and E. villosa var. maxima Stapf. Members of the group occur on sandy soils in the Succulent Karoo and Fynbos Biomes, along the west coast in Strandveld and on the southern coast as far east as the Fish River. Morphologically, the group appears to be related to the Calycina and Capensis groups.
Studies in the Ericoideae (Ericaceae). VI. The generic relationship between <i>Erica</i> and <i.Philippia</i> in southern Africa,
Authors: Oliver E. G. H. 
Published: July 2015

Problems in placing certain species satisfactorily in Philippia or Erica have led to an investigation of characters delimiting the genera mainly in southern African species. The only character used in placing problem species was partial versus total recaulescence of the bract. This separation breaks down completely in a few species in which ericoid and philippioid flowers occur within the same inflorescence. Not all species of Philippia are closely related, some being more closely related to various sections within Erica. It is evident that Philippia is an unnatural polyphyletic group. It is concluded that Philippia should be placed in synonymy under Erica.
Two closely related species of <i>Caloplaca</i> (Teloschistaceae, Lichenes) from the Namib Desert
Authors: Kärnefelt I. 
Published: July 2015

The anatomical and reproductive adaptations of two closely related lichen species. Caloplaca elegantissima (Nyl.) Zahlbr. and C. namibensis Karnef., sp. nov., occurring in the outer Namib fog desert, are discussed. Both species belong to the cmstose forms, frequently found in the remarkably rich lichen communities, which largely depend on fog precipitation for their water supply. Both species are endemic to the Namib Desert. They are mainly distributed in South West Africa/Namibia but also extend into south-western Angola. The asexual isidiate species. C. namibensis Karnef., is described as new.