A.E. van Wyk

Vegetation of the Tembe Elephant Park, Maputaland, South Africa

A hierarchical classification, vegetation map, description and ecological interpretation of the plant communities of the Tembe Elephant Park and surrounding areas are presented. The study area falls within the Maputaland Centre of Endemism, which is part of the Maputaland-Pondoland Region, a centre of plant diversity rich in endemic plants and animals. Sixty-four sample plots were distributed in a stratified manner throughout the study area. A TWINSPAN classification, refined by Braun-Blanquet procedures, revealed eight distinct, mainly woodland plant communities. Much of the vegetation distribution can be ascribed to vegetation dynamics and the geomorphological evolution of the region. Dynamics of water in the landscape either directly or indirectly, through its role in moisture levels and soil formation, plays a role in the determination of plant communities at the higher levels. The proposed classification and general descriptions can be used for nature reserve management, land-use planning and further research. Ordinations based on floristic data give an indication of floristic and associated habitat and environmental relationships. Soil character and moisture differences are usually slight, hence the sand-based communities do not have distinct boundaries, except for Sand Forest. Indications are that in the case of Sand Forest the distinct boundary zone of nearly bare soil may well be the result of allelopathy Eighty-four Maputaland Centre plant endemics/near-endemics were recorded for the study area, with Sand Forest being the most prolific habitat for such taxa, many which appear to be neoendemics. Because of its hypothesised origin (especially lack of specific historic events) and vegetation dynamics, the inclusion of Sand Forest in conservation areas is no guarantee of the future persistence of this rare vegetation type.

Patterns in the seed germination response to smoke in plants from the Cape Floristic Region, South Africa

De Lange and Boucher (1990) discovered the germination enhancing effect of plant-derived smoke on seed of fynbos species. This finding has been applied to horti- culturally important fynbos species and to date 301 species have been tested for a response to smoke. Germination in 150 (49.8%) of these was significantly improved by smoke treatment; the remaining 151 species showed no significant response. Families in which species showed a significant response included the horticulturally important Asteraceae (everlastings), Bruniaceae (brunias), Crassulaceae (crassulas), Ericaceae (ericas), Geraniaceae (pelargoniums), Mesembryanthemaceae (mesembs), Proteaceae (pro- teas) and Restionaceae (restios). No species responded in the families of geophytes such as Amaryllidaceae and Hyacinthaceae and in the Iridaceae the majority of species studied (also geophytes) did not respond. Further analysis of the germination results using ordinal logistic regression confirmed that the geophytic growth form was a robust predictor of response to smoke; geophytes exhibited a very low germination response to smoke. In addition, the analysis indicated that serotinous species had seeds that were less likely to respond to smoke than non-serotinous species, presumably as a consequence of their seeds not being in the soil when fire occurs. It also indicated that plants with some capacity to re-sprout were less likely to respond to smoke than obligate seeders.

Therapeutic uses of Aloe L. (Asphodelaceae) in southern Africa

ETHNOPHARMACOLOGICAL RELEVANCE The African-Arabian succulent genus Aloe L. (Aloaceae/Asphodelaceae) is represented by approximately 120 infrageneric taxa in southern Africa, including A. ferox Mill., a species long used in commercial natural products. AIMS OF THE STUDY To assess the documented ethnobotanical knowledge and biocultural value of utility in the genus in southern Africa. MATERIALS AND METHODS A survey of over 350 multidisciplinary publications was undertaken. RESULTS Local uses for medicine and wellbeing were identified for over half the species of Aloe occurring in the Flora of Southern Africa region. The most frequently cited medicinal uses were the treatment of infections and internal parasites, digestive ailments and injuries. Numerous species were recorded for their social uses, notably as ingredients in tobacco snuff. CONCLUSION The exceptional infrageneric diversity of Aloe, and extensive therapeutic uses in southern Africa, indicate its cultural importance in the subcontinent. These factors highlight the need for the conservation of the species as well as their potential as a source of natural products.

Endemic flora of the north-eastern Transvaal Escarpment, South Africa

Abstract The endemic seed plant flora of the north-eastern Transvaal Escarpment (part of the Afromontane Region) is assessed in terms of the regions lithology (mainly rocks of the Transvaal Sequence). A total of 81 species and infraspecific taxa are endemic or near-endemic to the quartzitic and related rock types of the Black Reef Quartzite Formation, Wolkberg Group and Timeball Hill Formation (c. 3880 km2) and a total of 32 species were recorded as endemic or near-endemic to the dolomitic Chuniespoort Formation (c. 2100 km2). As a major centre of biodiversity, we propose to name this escarpment region of Transvaal Sequence, the Wolkberg Centre. Two subunits of endemism are recognized: the Blyde Subcentre in the south, and the Serala Subcentre in the north. Although the number of endemics on dolomite is less than half the number on quartzite-derived substrates, the degree of endemism is higher on the former. The majority of dolomite epidemics are confined to the drier areas and are not of such strong Afromontane affinity as the quartzite ones. Nearly all the endemics are herbaceous, confirming to the observation that regional endemism levels in the Afromontane Region are high in grassland, but low among the tree flora of the patches of undifferentiated evergreen forest. The vegetation of the Wolkberg Centre, especially the grassland, is under considerable pressure, particularly from the timber industry and invasive alien plants. Existing and proposed conservation areas in the centre are listed.

Biodiversity of the Maputaland Centre

The Maputaland Centre [MC] of endemism comprises the northernmost part of the Tongaland-Pondoland Regional Mosaic. With the exception of the narrow Lebombo Range which rises to an elevation of some 600 m, the area is a nearly flat, low-level, sandy coastal plain with a maximum elevation of about 150 m. The vegetation of the MC is exceptionally diverse, consisting of a mosaic of forest, savanna, grassland and swamps, largely determined by local edaphic conditions. About 2,500 species (but probably more) of vascular plants occur in the MC. Of these at least 203 species/infraspecific taxa and 3 genera (Brachychloa, Galpinia, Helichrysopsis) are endemic/nearendemic to the region, and are listed for the first time. The area is also outstanding for its faunistic diversity, which includes many endemics spread over the whole taxonomic spectrum. Biogeographic links of the MC are clearly with the more tropical parts of Africa, with many Afrotropical species reaching the southernmost limit of their range here.

Molecular phylogenetic analysis of Eugenia L. (Myrtaceae), with emphasis on southern African taxa.

Abstract.With approximately 1000 species, Eugenia s.str. (excluding Syzygium) is one of the largest genera in the Myrtaceae. Morphological and anatomical studies concluded that two supraspecific groups (X and Y) exist in African members of Eugenia. A multigene approach was used to investigate phylogenetic/molecular relationships within southern African Eugenia, as well as representatives from elsewhere in the world. The cpDNA rpl16 intron data supported the distinctness of species groups X and Y. Little sequence divergence was found within the rpl16 intron of Eugenia. Nuclear sequence data were more variable than cpDNA and also supported the two groups. Combined data enhanced the resolution of closely related species. Species group X is related to Eugenia of the New World whereas the affinity of species group Y lies with Eugenia of the Old World. It is hypothesised that the origin of Eugenia in southern Africa is twofold. The presence of cryptic dioecy (structural androdioecy) in both groups of Eugenia in Africa is probably due to convergence. The suggestion that E. incerta is not native to Africa is supported by molecular evidence. The genus Monimiastrum is embedded within a clade with Mauritian Eugenia.

Acacia: The case against moving the type to Australia

Recent studies have shown that Acacia is polyphyletic and must be split into five genera. Proposal 1584 would retypify Acacia : the type of the Australian taxon A. penninervis would be conserved over the current lectotype ( A. scorpioides ) of an African taxon. We disagree with the recommendation of the Spermatophyte Committee to endorse this proposal. Contrary to Article 14.12 of the ICBN, no detailed case against conservation was presented in Proposal 1584. We maintain that there are strong arguments against conservation, such as the large number of countries that would be affected, the economic importance of the extra-Australian species, and the economic burden placed on developing countries. Acceptance of this proposal would also violate the guidelines for conservation which clearly state that the principle of priority should prevail when conservation for one part of the world would create disadvantageous change in another part of the world.

Pollen types in the lauraceae

Abstract Pollen morphology of southern African Lauraceae (Cassytha, Cryptocarya, Dahlgrenodendron, Ocotea) and members of the genera Beilschmiedia, Eusideroxylon, Hypodaphnis, Lindera and Potoxylon was studied by means of light and scanning electron microscopy. Pollen morphologically the various genera could readily be distinguished from each other, but few interspecific differences were found. To assess the taxonomic significance of pollen characters in Lauraceae, evidence from the literature was also considered and compared with the infrafamilial classification proposed by Kostermans. On the basis of mainly shape and exine sculpture, four pollen types are distinguished in Lauraceae. Pollen type A (grains spheroidal, apolar, spinulose) has been only recorded in the tribes Perseeae, Cinnamomeae, Litseeae and Hypodaphneae; pollen type B (oblate/peroblate, isopolar, slightly to strongly verrucate) occurs only in the Cryptocaryeae; pollen type C (spheroidal, apolar, strongly verrucate/spinuloid) is character...

The genus Eugenia (Myrtaceae) in southern Africa: Ontogeny and taxonomic value of the seed

Eugenia L. in southern Africa constitutes two coordinate groups of species (groups X and Y). Each group is characterized by a particular type of seed (types X and Y respectively). This study concerns the ontogeny of both seed types. Results are compared with the literature to evaluate its taxonomic significance. In both groups the ovules are hemi-campylotropous, occasionally tending to be ana-campylotropous, sessile or sub-sessile, bitegmic and crassinucellate. Usually only one ovule per ovary matures into an overgrown seed. Abortive ovules are transformed into ovulodes. Ovules in seed type X become amphitropous resulting in sub-reniform or oblong-globose seed. A short funicle is discernible; the hilum is not extended. The testa develops from the outer integument and is relatively thin (0,1 – 0,5 mm), not multiplicative and tends to be exotestal. Two areolae pervaded by vascular strands are present. Secretory cavities develop in the cotyledons. Starch, occasionally with unidentified spherical bodies, is the main storage product. Abundant endosperm is formed. Seed type Y is globose, pachychalazal and sessile with an extended hilum. The testa is relatively thick (0,5 – 1,0 mm), multiplicative, mesotestal and pervaded by vascular strands. Secretory cavities are absent from the cotyledons. Starch is the only storage product. Relatively little endosperm is formed. Generic rank is proposed for both groups. Group X is treated as congeneric with Eugenia s. str. whereas group Y probably represents a new generic segregate.

Bark medicines used in traditional healthcare in KwaZulu-Natal, South Africa: An inventory

Bark is an important source of medicine in South African traditional healthcare but is poorly documented. From thorough surveys of the popular ethnobotanical literature, and other less widely available sources, 174 species (spanning 108 genera and 50 families) used for their bark in KwaZulu-Natal, were inventoried. Vernacular names, morphological and phytochemical properties, usage and conservation data were captured in a database that aimed to synthesise published information of such species. Data specificity was found to be the major limiting factor in the study and resulted in uneven distribution of information in the database. Overlapping vernacular names recorded in the literature indicated that it may be unreliable in local plant identifications. Most (43%) bark medicines were documented for the treatment of internal ailments. Sixteen percent of species were classed in threatened conservation categories, but conservation and management data were limited or absent from a further 62%. There is a need for research and specialist publications to address the gaps in existing knowledge of medicinal bark species and their management to conserve the South African flora.