Abstract: Environmental conditions encountered in arid ecosystems differ vastly from those in more mesic ecosystems. Dispersal strategies in arid environments reflect these differences and many mechanisms have evolved that restrict or hinder dispersal. Myxospermy is a trait developed by plant species from arid regions to restrict diaspore dispersal by means of an anchorage mechanism. Several of the abundant plant species in Namaqualand, within the arid Succulent Karoo Biome, display myxospermy. Diaspores of these species produce copious amounts of mucilage when they are moistened and are anchored to the soil once the mucilage dries out again. This study investigated the origin of the mucilaginous layer of 12 species anatomically, using both light and scanning electron microscopy. The mucilage production of the species investigated could best be grouped into three types: 1, epidermal and sub-epidermal cells of seeds and achenes; 2, specialized tissue in wings or the pappus of achenes; and 3, mucilage excreting hairs. Previous systems for classifying the different types of mucilage production did not recognize the mucilaginous nature of wings or a pappus. A short note on the composition of the mucilage is included.

Abstract: The native and naturalized species of Silene L. in southern Africa are reviewed, with full synonomy and the description of two new species from the West Coast of Western Cape. Eight native species and three naturalized species are recognized, including the first identification in southern Africa of the Mediterranean S. nocturna L. The identity of S. aethiopica Burm., which has remained unknown since its description, is established and is found to be the oldest name for S. clandestina Jacq. Patterns of morphological variation within each species are discussed and subspecies are recognized for geographically segregated groups of populations that are ± morphologically diagnosable. The following new names or combinations are made among the southern African taxa: S. aethiopica subsp. longiflora ; S. burchellii subsp. modesta , subsp. multiflora , and subsp. pilosellifolia ; S. crassifolia subsp. primuliflora ; S. saldanhensis ; S. rigens ; and S. undulata subsp. polyantha . Each taxon is described, with information on ecology and distribution, and most species are illustrated, including SEM micrographs of the seeds.

Abstract: The southern African genus Ixia L. comprises ± 90 species from the winter-rainfall zone of the subcontinent. Ixia sect. Dichone (Salisb. ex Baker) Goldblatt & J.C.Manning, one of four sections in the genus and currently including 10 species and three varieties, is distinguished by the following floral characters: lower part of the perianth tube filiform and tightly clasping the style; filaments not decurrent; upper part of the perianth tube short to vestigial; style branches involute-tubular and stigmatic only at the tips; and so-called subdidymous anthers. We review the taxonomy of the section, providing complete descriptions and distribution maps, and a key to the species. I. amethystina Manning & Goldblatt is recognized to be a later synonym of I. brevituba G.J.Lewis. Most collections currently included under that name represent another species, here described as I. rigida . We recognize five additional species in the section: early summer-blooming I. altissima from the Cedarberg; I. bifolia from the Caledon District; I. flagellaris , a stoloniferous species from the Cedarberg; I. simulans from the western Langeberg; and I. tenuis from the Piketberg. We also raise to species rank I. micrandra var. confusa and var. minor , as I. confusa and I. minor respectively. Foliar and associated floral variation in the widespread I. scillaris has led us to recognize two new subspecies among its northern populations, broad leaved subsp. latifolia and the dwarfed, smaller flowered subsp. toximontana ; subsp. scillaris is restricted to the immediate southwestern Cape, from Darling to Somerset West. Sect. Dichone now has 17 species and two subspecies.

Abstract: A taxonomic revision of the genus Sphenostylis E.Mey. (tribe Phaseoleae) in southern Africa is presented. The genus is distinguishable by its characteristic wedge-shaped, dorsiventrally flattened style tip. Of the seven known species in the genus, only two, S. angustifolia and S. marginata , occur in South Africa and Swaziland; and the former is endemic to these countries. The two species differ in the size, shape, and venation of the leaflets; as well as the length of the petiole, peduncle, and pod. A key to the two species is provided and the correct nomenclature, typification, and known geographical distributions are given.

Abstract: Field and laboratory research has shown that the Moraea tripetala complex of western South Africa, traditionally treated as a single species, sometimes with two additional varieties, has a pattern of morphological and cytological variation too complex to be accommodated in a single species. Variation in floral structure, especially the shape of the inner tepals, degree of union of the filaments, anther length and pollen colour form coherent patterns closely correlated with morphology of the corm tunics, mode of vegetative reproduction, and in some instances capsule and seed shape and size. The morphological patterns also correlate with geography, flowering time and sometimes habitat. It is especially significant that different variants of the complex may co-occur, each with overlapping or separate flowering times, a situation that conflicts with a single species taxonomy. We propose recognizing nine species and three additional subspecies for plants currently assigned to M. tripetala . M. grandis , from the western Karoo, has virtually free filaments and leaves often ± plane distally; closely allied M. amabilis , also with ± free filaments and often hairy leaves, is centred in the western Karoo and Olifants River Valley. Its range overlaps that of M. cuspidata , which has narrowly channelled, smooth leaves, linear inner tepals spreading distally and filaments united for up to 1.5 mm. M. decipiens from the Piketberg, M. hainebachiana , a local endemic of coastal limestone fynbos in the Saldanha District, M. ogamana from seasonally wet lowlands, and early flowering M. mutila constitute the remaining species of the complex in the southwestern Western Cape. M. helmei , a local endemic of middle elevations in the Kamiesberg, Namaqualand, has small flowers with short, tricuspidate inner tepals. All but M. amabilis and M. mutila are new species. We divide M. tripetala sensu stricto into three subspecies: widespread subsp. tripetala , subsp. violacea from the interior Cape flora region, and late-flowering subsp. jacquiniana from the Cape Peninsula and surrounding mountains.

Abstract: Babiana rivulicola from stream banks in the Kamiesberg in Namaqualand and terete-leaved Ixia teretifolia from the Roggeveld, both in Northern Cape, are new species of these two largely winter-rainfall region genera. Late-flowering populations of Hesperantha radiata with crowded spikes of smaller flowers are segregated from the typical form as subsp. caricina . We also document the first record of B. gariepensis from Namibia, correct the authority for B. purpurea Ker Gawl., discuss morphologically aberrant populations of B. tubiflora from Saldanha, provide an expanded description for B. lapeirousiodes based on the second and only precisely localized collection of this rare Namaqualand species, and expand the circumscription of Geissorhiza demissa to accommodate a new record from the Kamiesberg, including revised couplets to the existing key to the species.

Abstract: Ceterachoid aspleniums in southern Africa have long been treated as a single widespread and variable taxon, Asplenium cordatum (Thunb.) Sw. (= Ceterach cordatum Thunb.). In addition to A. cordatum , a further two ceterachoid taxa are now recognized as occurring in the Flora of southern Africa (FSA) region, namely A. capense (Kunze) Bir, Fraser-Jenk. & Lovis and A. phillipsianum (Kummerle) Bir, Fraser-Jenk. & Lovis. We provide full descriptions and distributions of these three taxa.

Abstract: Family Tecophilaeaceae subfam. Tecophilaeoideae is revised for the Flora of southern Africa region, with the inclusion of the tropical Walleria mackenzii J.Kirk for completeness. The genera Cyanella Royen ex L. (9 spp.), Eremiolirion J.C.Manning & F.Forest (1 sp.) and Walleria J.Kirk (3 spp.) are treated, with keys to the genera, species and subspecies; and full descriptions and distribution maps. A formal infrageneric classification is proposed for Cyanella , in which sect. Trigella (Salisb.) Pax & K.Hoffm. is revived for the species with a 3 + 3 arrangement of stamens. The new species, C. marlothii J.C.Manning & Goldblatt, is described from the Richtersveld; and C. pentheri Zahlbr. is resuscitated from the synonomy of C. hyacinthioides Royen ex L. Pink-flowered plants of normally yellow-flowered C. lutea have a separate geographical distribution and are recognized as subsp. rosea (Eckl. ex Baker) J.C.Manning & Goldblatt.

Abstract: An ‘early detection’-based desktop study has identified 23 taxa as ‘current’ emerging invasive alien plants in the Drakensberg Alpine Centre (DAC) and suggests a further 27 taxa as probable emerging invaders in the future. These 50 species are predicted to become problematic invasive plants in the DAC because they possess the necessary invasive attributes and have access to potentially suitable habitat that could result in them becoming major invaders. Most of the ‘current’ emerging invasive alien plant species of the DAC are of a northern-temperate affinity and belong to the families Fabaceae and Rosaceae (four taxa each), followed by Boraginaceae and Onagraceae (two taxa each). In terms of functional type (growth form), most taxa are shrubs (9), followed by herbs (8), tall trees (5), and a single climber. The need to undertake a fieldwork component is highlighted and a list of potential study sites to sample disturbed habitats is provided. A global change driver such as increased temperature is predicted to not only result in extirpation of native alpine species, but to also possibly render the environment more susceptible to alien plant invasions due to enhanced competitive ability and pre-adapted traits. A list of emerging invasive alien plants is essential to bring about swift management interventions to reduce the threat of such biological invasions.