Showing papers in "Bothalia in 2006"

Floristic composition of gold and uranium tailings dams, and adja­cent polluted areas, on South Africa’s deep-level mines

Abstract: Gold and uranium tailings (‘slimes’) dams and the adjacent polluted soils in the deep-level mining regions of South Africa (Carletonville, Klerksdorp and Welkom) were surveyed for the frequency of occurrence of naturally colonizing, actively introduced and persisting plant species. Fifty-six tailings dams with a combined area of 5864 ha. and a similar area o f tail- ings-polluted soils, were surveyed between July 1996 and March 1997. During the survey, 376 plant species and subspecies were recorded from the dams and adjacent polluted soils, with an additional 8 6 records obtained between 1998 and 2003 (i.e. a total of 462 taxa: species and infraspecific species). Overall, the most commonly represented families were the Poaceae (107 species and subspecies), Asteraceae (81). Fabaceae (55) and Anacardiaceae (16). with other families represented by just one to 14 species. Only 60 species were common to all three regions, and of these 24 had been introduced during rehabilitation attempts. Most of the species found on tailings were persisters or natural colonizers (53-88%, depending on substrate), with the vast majority being indigenous and perennial taxa (76% and 85% respectively), with semi-woody to woody growth forms (6 6% being resprouters, forbs, shrubs and trees). Less than 4% of the naturally-colonizing taxa found during the survey had also been introduced by vegetation practitioners. The majority of introduced plants were alien herbaceous taxa. The number and frequency of annuals was only high on recently vegetated sites, whereas annuals were rarely present on old-vegetated and never-vegetated dams. This list includes a wide range of indigenous plant species that may be suitable for phytoremediation of tailings dams and polluted soils due to their apparent tolerance of acid mine drainage and salinity.

Comparisons of invasive plants in southern Africa originating from southern temperate, northern temperate and tropical regions.

Abstract: A subset of invasive alien plant species in southern Africa was analysed in terms of their history of introduction, rate of spread, countries/region of origin, taxonomy, growth forms, cultivated uses, weed status and current distribution in southern Africa, and comparisons made of those originating from south of the tropic of Capricorn, north of the tropic of Cancer and from the tropics. The subset of 233 species, belonging to 58 families, includes all important declared species and some potentially important species. Almost as many species originate from temperate regions (112) as from the tropics (121). Most southern temperate species came from Australia (28/36), most tropical species from tropical America (92/121) and most northern temperate species from Europe (including the Mediterranean) and Asia (58/76). Transformers account for 33% of all species. More transformers are of tropical origin (36) than of northern temperate (24) and southern temperate origin (18). However. 50% of southern temperate species are transformers, compared to 32% of northern temperate and 29% of tropical species. Southern temperate transformer species are mainly woody trees and shrubs that were established on a grand scale as silvicultural crops, barriers (hedges, windbreaks and screens) and cover/binders. Most aquatics, herbs, climbers and succulent shrubs an. trom the tropics. Ornamentals are the single largest category of plants from all three regions, the tropics having contributed twice as many species as temperate regions.

Patterns of plant diversity and endemism in Namibia

Abstract: Species richness, endemism and areas that are rich in both species and endemic species were assessed and mapped for Namibia. High species diversity corresponds with zones where species overlap. These are particularly obvious where there are altitudinal variations and in high-lying areas. The endemic flora of Namibia is rich and diverse. An estimated 16% of the total plant species in Namibia are endemic to the country. Endemics are in a wide variety of families and sixteen genera are endemic. Factors that increase the likelihood of endemism are mountains, hot deserts, diversity of substrates and microclimates. The distribution of plants endemic to Namibia was arranged in three different ways. Firstly, based on a grid count with the phytogeographic value o f the species being equal, overall endemism was mapped. Secondly, range restricted plant species were mapped individually and those with congruent distribution patterns were combined. Thirdly, localities that are important for very range-restricted species were identified. The resulting maps o f endemism and diversity were compared and found to correspond in many localities. When overall endemism is compared with overall diversity, rich localities may consist of endemic species with wide ranges. The other methods identify important localities with their own distinctive complement of species.

Sesotho names for exotic and indigenous edible plants in southern Africa

Abstract: A comprehensive checklist of Sesotho names of both indigenous and exotic food plants is presented, based on a literature survey and the first author's experience. The list includes the scientific names. English common names and parts of the plant that are used. Where possible, the origin or meaning of the Sesotho names is given. Exotic edible plants for which the English common names are in general use have been excluded. The list includes 164 indigenous and 39 names of exotic species.

New species of Iridaceae from the Hantam-Roggeveld Centre of Endemism, and the Bokkeveld, Northern Cape, South Africa

Abstract: Three new species of Iridaceae are described from the Bokkeveld and Roggeveld Escarpments. Ixia amethystina . a member of section Dichone , is endemic to the edge of the Roggeveld Escarpment. It shares an unusual, inclined spike that is nodding in bud with I. trifolia but is distinguished by its blackish purple (not yellow) anthers, narrower leaves 1.5-2.0 mm wide, medium-textured corm tunics that form a distinct neck at the base of the stem, and short style branches 2.0-2.5 mm long. Moraea marginata . another Roggeveld endemic, is a member of section Polvanthes and florally similar to M. fistulosa and M. monticola but differs in its linear, channelled leaves 5-7 mm wide, with unusual, thickened margins. Romulea singularis . from the edge of the Kobee River Valley in the Bokkeveld Mountains, is a member of section Ciliatae. It is unique in the genus in its narrowly funnel-shaped, mauve to purple flowers with slender perianth tube 10-11 mm long, and unusually long filaments, 8-9 mm long, inserted in the lower half of the tube.

Two new species of Spiloxene (Hypoxidaceae) from the northwestern Cape, South Africa

Abstract: Newly described are two new species of Spiloxene Salisb.: S. nana Snijman from the Bokkeveld Escarpment, Northern Cape Province, is a shade-loving plant with narrow, pale green leaves and small, white or rarely cream-coloured flowers; S. pusilla Snijman from the Matsikamma, Gifberg and Pakhuis Mountains. Western Cape Province, resembles S. nana in habit but the yellow- or white-tepalled flowers which are tetramerous or hexamerous have darkly coloured stamens and style and an ovary with a short, solid, narrow prolongation at the apex. Inhabiting rock overhangs formed by quartzitic sandstone sheets, both species are close allies of S. scullyi (Baker) Garside from Namaqualand.

Hypoxis (Hypoxidaceae) in Africa: list of species and infraspecific names

Abstract: A list of species and synonyms is presented for the African Hypoxis L. An abbreviated reference to the original publication of a species is included in the list. Distribution of taxa is indicated by the country in which they occur. A list of synonyms with accepted or suggested names and the reference to change in status of a taxon is provided. Subsequent publications on the treatment of a taxon are given to denote congruous and differing resolution of taxa by authorities.

Reappraisal and identification of Olinia rochetiana (Oliniaceae) in South Africa

Abstract: A numerical phenetic analysis of data obtained from populations of the Olinia rochetiana A.Juss. complex occurring in South Africa (Mpumalanga and Limpopo Provinces) revealed the existence of two forms: 1, a shrubby form (up to 2.5 m tall), with thick terminal branches, coriaceous leaves with a tinge of red on margins (towards the apices),short inflorescence axes, peduncles and deeply red pedicels and floral tubes/hypanthia: and 2, a slender tree form, measuring more than 4 m tall with slender terminal branches, glossy and slightly thin, papery leaves, margin colour the same as the entire lamina, and the inflor­escence axes, peduncles, pedicels and hypanthia pale green to creamy white. Differences in floral features between the twoforms correlate with differences observed in vegetative features. The two forms occupy distinct ecological niches and show tolerances and preferences for different environmental conditions such as soil type,elevation and humidity. An identificationkey for the two forms is presented.

New species and taxonomic changes within Pentaschistis (Danthonioideae, Poaceae) from Western Cape, South Africa

Abstract: Three new species of Pentaschistis (Nees) Stapf are described from the Cape Floristic Region. P. trifida . P clavata and P. horrida . The former has been collected from inland ranges of the Cape Fold Belt, from the Cederberg to the Groot Swartberg. the last two each from single sites in the Koue Bokkeveld: P. clavata on the wetter western border, and P. horrida on the Baviaansberg. Pentaschistis juncifolia Stapf is re-instated, a species from the coastal plains (Hardeveld) between Bredasdorp and Riversdale, which had been included in P. eriostoma (Nees) Stapf.

Two new species of Nemesia (Scrophulariaceae) from southern Africa

Abstract: Two new annual species of Nemesia Vent, are described from southern Africa. N. williamsonii is characterized by bright orange flowers with an inflated yellow palate. It differs from the related N. maxii Hiern by having a spur that projects backwards, not downwards, and bracts that are lanceolate with a truncate base, not triangular or cordate. It is unusual for the genus in having dimorphic seeds. N. williamsonii occurs almost exclusively in the Richtersveld. but has been collected in a few localities across the Orange River in southern Namibia. N. hemiptera is a delicate, wiry-stemmed annual with small white flowers. The flowers are characterized by a tiny nipple-like spur and a seed that is winged on onlv one side. N. hemiptera isendemic to the Kamiesberg from near Garies to Kamieskroon.

Phytogeography of Passerina (Thymelaeaceae)

Abstract: Passerina L comprises 20 species and four subspecies of microphyllous wind-pollinated shrubs Once considered cos­mopolitan, the genus as currently defined, is endemic to southern Africa Endemism within the genus is highest in the Cape Floristic Region (CFR), where all members show morphological and anatomical adaptations to the winter rainfall and dry warm summers of the Mediterranean or semi-Mediterranean climate of the region The Western Cape is the centre of diversity for Passerina, from where certain species extend to the west, north and east The outlier populations of Passerina montana Thoday on the interior plateau of South Africa and Zimbabwe, as well as the Auas Moutains in Namibia, most probably origi­nated in the CFR and formed part of a previously wider northern temperate Afromontane grassland-dominated vegetation during the Quartemary, of which relicts remained in the high mountain areas P burchellii Thoday and P paludosa Thoday have the most restricted distribution and are regarded as Vulnerable All other species are either widespread or under no im­mediate threat

Three new species of Lachenalia (Hyacinthaceae: Massonieae) from Western and Northern Cape, South Africa

Abstract: This is the sixth in a series of papers on Lachenalia , towards a revision of the genus. Three new species are described. L. lutea from the southwestern part of the Western Cape, L. cernua from the southern Cape Peninsula and the Worcester Valley of the Western Cape, and L. nardousbergensis from the Bokkeveld Plateau of the Northern Cape, and the Nardousberge and Middelburg Plateaus of the Western Cape.

Two new species of Commiphora (Burseraceae) from southern Africa

Abstract: Commiphora steynii Swanepoel and C. gariepensis Swanepoel, here described as new species, are known only from the Kaokoveld and Gariep Centres of Endemism respectively. Illustrations of the plants and distribution maps are provided. Diagnostic characters of C . steynii include the pale ashy grey, non-peeling bark and the lack of wart-like projections around the large lenticels. Diagnostic characters of C. gariepensis include the stamen number which varies between four and eight, and the milky-watery latex which does not squirt when branches are damaged. When without leaves or fruit , C. gariepensis can easily be confused with several other species. Comprehensive tables with diagnostic morphological features to distinguish between the new species and closely related taxa are presented.

Two new species of Erica (Ericaceae) from the Langeberg, Western Cape, South Africa

Abstract: Two new species of the genus Erica L. from the north-facing slopes of the Langeberg are described— E turneri , known only from the type locality on Zuurbraak Mountain and E. euryphylla , occurring on the same mountain slope, as well as on the middle north-facing slopes of Hermitage Peak near Misty Point in the Marloth Nature Reserve above Swellendam.

A taxonomic revision of the genus Merciera (Campanulaceae)

Abstract: A taxonomic account of Western Cape endemic genus Merciera A.DC. is presented. Six species, supported by recent phenetic studies, are recognized. M. brevifolia A.DC., M. eckloniana H.Buek. M. leptoloba A.DC. and M. tenuifolia (L.f.) A.DC are retained as species. M. azurea Schltr. is returned to species status and M. tetraloba C.N.Cupido was recently described. Each species is described and illustrated. A key to the species, and distribution maps are provided.

Forsyth (fl. 1835)’: a phantom botanical collector at the cape of good hope explained

Abstract: BOLUS. H.M.L. 1929. Notes on Mesembryanthemum and allied gen­ era, part 2: 121 DESMET, P. 2000. Captions to slides for MSG. Mesemb StudV Group Bulletin 4: 64. GLEN, H.F. 1986. Numerical taxonomic studies in the subtribe Ruschiinae (Mesembryanthemaceae)— Astridia, Acrodon and Ebracteola. Bothalia 16: 203-226. HARTMANN, H.E.K. 1996. Miscellaneous taxonomic notes on Aizoaceae. Bradleya 14: 20-56. HARTMANN, H.E.K. 1998a. New combinations in Antimima (Ruschioideae, Aizoaceae) from southern Africa. Bothalia 28: 67-82. HARTMANN, H.E.K. 1998b. New combinations in Ruschioideae, based on studies in Ruschia (Aizoaceae). Bradleya 16: 44-91. HARTMANN, H.E.K. 2001. Illustrated handbook o f succulent plants: Aizoaceae A-E. Springer-Verlag, Berlin. HAWORTH, A.H. 1812. Synopsis plantarum succulentarum. 283. Taylor, London. HILTON TAYLOR. C. 1996. Red Data List o f southern African plants. Strelitzia 4. National Botanical Institute, Pretoria. IUCN 2001. IUCN Red List Categories and Criteria: version 3.1. IUCN Species Survival Commission. IUCN, Gland. Switzerland and Cambridge, UK. KLAK. C. & VICTOR. J.E. 2001. Red List data. South African National Biodiversity Institute. Pretoria. Unpublished. SALM-REIFFERSCHEIDT-DYCK. J. Duke of. 1836-1863. Monographia generum Aloe et Mesembryanthemi. I-V: Amz. Dusseldorf; V. VI: Henry & Cohen. Bonn; VII: M. Cohen & fil.. Bonn. SMUTS, L.M. 1994. ISEP (Information System fo r Endangered Plants) file. Cape Nature Conservation. Unpublished. SOUTH AFRICAN COMMITTEE FOR STRATIGRAPHY (SACS) 1980. Stratigraphy o f South Africa. Part 1 (compiled by L.E. Kent). Lithostratigraphy o f the Republic o f South Africa. South West Africa/Namibia, and the Republics o f Bophuthatswana. Transkei and Venda. Handbook o f the Geological Sur\\'ey o f South Africa No. 8: 201-235. Government Printer. Pretoria.

Notes on the systematics and nomenclature of Tritonia (Iridaceae: Crocoideae)

Abstract: Study of some early types of species now known to belong to the genus Tritonia Ker Gaw l.. a member of Iridaceae. sub­ family Crocoideae, comprising some 28 species of southern and south tropical Africa, has shown the need for some nomen- clatural adjustments. Ixia undulata Burm.f. (1768) is an earlier name for T. crispa (L.f.) Ker Gawl. based on Gladiolus crispus L.f. (1782) and the combination T. undulata (Burm.f.) Baker must be used for the species, which is native to the western half of Western Cape, South Africa. The variety T. crispa var. parx iflora is also reduced to synonymy. The type specimen of Ixia gladiolaris Lam. (1789), currently considered a synonym of Tritonia securigera (Aiton) Ker Gawl.. has flowers that lack the characteristic tooth-like ridges on the lower tepals of the latter, and corresponds closely to the eastern southern African T. lineata (Salisb.) Ker Gawl., based on Gladiolus lineatus Salisb. (1796). The new combination T. gladiolaris (Lam.) Goldblatt & J.C. Manning is made and T. lineata is reduced to synonymy. Montbretia lacerata and Tritonia lacerata. erroneously regarded as synonyms of T. crispa , are combinations based on Gladiolus laceratus Burm.f., a species that remains unidenti­ fied because no type is known and the description is too vague to permit its identification. Lastly, field studies have shown that the cnsped-leaved T. watermeveri is connected by a series of morphological intermediates to typical T. securigera . which has straight leaves and identical flowers. The new combination T. securigera subsp. watermeveri (L.Bolus) J.C.Manning & Goldblatt is proposed for this taxon.