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This study investigates genetic diversity in three species of Ephemeroptera, one eurytopic and therefore widespread (Afroptilum sudafricanum) and two stenotopic and thus endemic (Demoreptus natalensis and Demoreptus capensis) species, all of which co-occur in the southern Great Escarpment, South Africa. Mitochondrial DNA was analysed to compare the genetic diversity between the habitat generalist and the two habitat specialists. Afroptilum sudafricanum showed no indication of population genetic structure due to geographic location, while both Demoreptus species revealed clear genetic differentiation between geographic localities and catchments, evident from phylogenetic analyses and high FST values from AMOVA. In addition, the phylogenetic analyses indicate some deeper haplotype divergences within A. sudafricanum and Demoreptus that merit taxonomic attention. These results give important insight into evolutionary processes occurring through habitat specialisation and population isolation. Further research and sampling across a wider geographic setting that includes both major mountain blocks of the Escarpment and lowland non-Escarpment sites will allow for refined understanding of biodiversity and associated habitat preferences, and illuminate comparative inferences into gene flow and cryptic speciation. [ABSTRACT FROM AUTHOR]

Global climate change is a major challenge for the future with serious potential impacts on biodiversity. Biodiversity in mountains is particularly vulnerable as many montane species are adapted to narrow microhabitats, making them less able to adjust to a climatic change. It is considered important to investigate range changes in the South African Great Escarpment because of the high levels of biodiversity in these mountains, as well as their importance for water provision in South Africa. The current and future ranges of 46 montane plant species in South Africa and Lesotho were therefore modelled using biomod in R, using presence points and predictor variables which included rainfall and temperature worldclim layers. The performance of distribution models produced was evaluated using the Area Under the receiver operating Curve (AUC), True Skill Statistic (TSS), Sensitivity and Specificity. We calculated beta diversity and species richness changes between current and future climates for the group of 46 species, as well as shifts of the predicted presence region boundaries and centroids. We also analysed shifts in minimum, median and maximum elevations. Results show a contraction in species' ranges towards higher elevation as has been documented from other mountain regions around the world. These results are a cause for concern as a warming climate is decreasing the potential regions of occurrence of montane species in South Africa and Lesotho's mountainous regions of high biodiversity. This region is under a diverse range of conservation and land use management practises, and our results suggest a coordinated response to climate change is needed. [ABSTRACT FROM AUTHOR]

South Africa's 800 km-long southern Great Escarpment hosts numerous endemic plant species only known from their type specimens or from very few records. This is a legacy of a 100-150 year lag between the pioneer work of 19th century botanists and repeat fieldwork in the 21st century. As a result, population and ecological data are lacking for many local endemic species. Here we report on the rediscovery of Lotononis harveyi B.-E.van Wyk 147 years after its original description, and provide the first detailed ecological notes on the poorly known shrub Macowania revoluta Oliv. Both species are locally endemic to the Great Winterberg-Amatholes (Eastern Cape Province). With only six known individuals, L. harveyi is recommended the conservation status of Critically Endangered, with fire (and potentially grazing) being the main population constraints. Macowania revoluta is locally abundant, and it is surprising that it has been so poorly collected in recent decades. It occupies an important local niche as a keystone montane wetland species, and its narrow distribution range -- combined with pressure from woody alien invasive species -- suggests that its conservation status should be Rare. The research further highlights the need for continued biodiversity field research along South Africa's poorly explored Great Escarpment. [ABSTRACT FROM AUTHOR]

Two new species of Indigofera L. (Leguminosae) are described from the Sneeuberg Centre of Floristic Endemism on the southern Great Escarpment, Eastern and Western Cape Provinces, South Africa. Both species are localised high-altitude endemics. Indigofera magnifica Schrire & V.R. Clark is confined to the summit plateau of the Toorberg--Koudeveldberg--Meelberg west of Graaff-Reinet, and complements other western Sneeuberg endemics such as Erica passerinoides (Bolus) E.G.H. Oliv. and Faurea recondita Rourke & V.R. Clark. Indigofera asantasanensis Schrire & V.R. Clark is confined to a small area east of Graaff-Reinet, and complements several other eastern Sneeuberg endemics such as Euryops exsudans B. Nord & V.R. Clark and E. proteoides B. Nord. & V.R. Clark. Based on morphology, both new species belong to the Cape Clade of Indigofera, supporting a biogeographical link between the Cape Floristic Region and the Sneeuberg, as well as with the rest of the eastern Great Escarpment. [ABSTRACT FROM AUTHOR]

Baits or lures are commonly used for surveying small mammal communities, not only because they attract large numbers of these animals, but also because they provide sustenance for trapped individuals. In this study we used Sherman live traps with five bait treatments to sample small mammal populations at three high-altitude sites (>1700 m) in the Sneeuberg Mountain Complex of the Eastern Cape Province, South Africa.We investigated the influence of bait treatment on three parameters commonly recorded in small mammal surveys. In addition, we investigated how different bait treatments vary in measuring species richness using the Chao 2 species richness estimator together with rarefaction curves. Overall, 12 small mammal species were sampled. A combination of birdseed and banana captured the highest number of species (11) but the most successful bait overall was peanut butter and oats (greatest number of captures, recaptures, number of individuals and highest Shannon diversity). The Chao 2 richness estimator indicated that four of the five bait treatments reached their sampling capacity. Rarefaction curves indicated that all bait treatments are similar with regard to species accumulation. This could possibly be explained by odours left behind in traps as even un-baited traps (i.e. controls) captured seven different small mammal species. We conclude that the most suitable bait for surveying small mammals at high altitude in South Africa is peanut butter and oats. However, using peanut butter and oats in combination with other bait treatments will improve estimates of diversity when surveying small mammal communities. [ABSTRACT FROM AUTHOR]

Background: Baetis harrisoni Barnard is a mayfly frequently encountered in river studies across Africa, but the external morphological features used for identifying nymphs have been observed to vary subtly between different geographic locations. It has been associated with a wide range of ecological conditions, including pH extremes of pH 2.9-10.0 in polluted waters. We present a molecular study of the genetic variation within B. harrisoni across 21 rivers in its distribution range in southern Africa. Results: Four gene regions were examined, two mitochondrial (cytochrome c oxidase subunit I [COI] and small subunit ribosomal 16S rDNA [16S]) and two nuclear (elongation factor 1 alpha [EF1α] and phosphoenolpyruvate carboxykinase [PEPCK]). Bayesian and parsimony approaches to phylogeny reconstruction resulted in five well-supported major lineages, which were confirmed using a general mixed Yule-coalescent (GMYC) model. Results from the EF1α gene were significantly incongruent with both mitochondrial and nuclear (PEPCK) results, possibly due to incomplete lineage sorting of the EF1α gene. Mean between-clade distance estimated using the COI and PEPCK data was found to be an order of magnitude greater than the within-clade distance and comparable to that previously reported for other recognised Baetis species. Analysis of the Isolation by Distance (IBD) between all samples showed a small but significant effect of IBD. Within each lineage the contribution of IBD was minimal. Tentative dating analyses using an uncorrelated log-normal relaxed clock and two published estimates of COI mutation rates suggest that diversification within the group occurred throughout the Pliocene and mid-Miocene (~2.4-11.5 mya). Conclusions: The distinct lineages of B. harrisoni correspond to categorical environmental variation, with two lineages comprising samples from streams that flow through acidic Table Mountain Sandstone and three lineages with samples from neutral-to-alkaline streams found within eastern South Africa, Malawi and Zambia. The results of this study suggest that B. harrisoni as it is currently recognised is not a single species with a wide geographic range and pH-tolerance, but may comprise up to five species under the phylogenetic species concept, each with limited pH-tolerances, and that the B. harrisoni species group is thus in need of taxonomic review. [ABSTRACT FROM AUTHOR]

Albuca tenuifolia Baker was described and illustrated in 1872 from South African material sent by Peter MacOwan to William Wilson Saunders in England, without a precise locality. Since then this species has been cited in later works although with many uncertainties. In addition, no type has been designated for this taxon. After field work in the Great Escarpment in South Africa, some populations of A. tenuifolia have been rediscovered growing in rocky places at high altitude. Data on morphology, ecology, and distribution are reported, and a lectotype and epitype are designated to fix the use of the name. Affinities with other species are also discussed. [ABSTRACT FROM AUTHOR]

A new species of Psoralea is described. Psoralea margaretiflora C.H. Stirton & V.R. Clark is endemic to the Sneeuberg Centre of Floristic Endemism, Eastern Cape, South Africa. This resprouter is characterised by its small greenish-white flowers with a small trifid purple nectar patch and translucent veins; 5(-7)-pinnate leaflets; multi-branching erect short seasonal flowering shoots; and tall habit of many stiff bare stems with the seasonal shoots massed at the apex. It is most similar to P. oligophylla Eckl. & Zeyh., a widespread species found in the Eastern Cape. The reseeder P. oligophylla differs in its lax virgate spreading habit with numerous long glaucous seasonal shoots; single stem, 1(-3)- glaucous leaflets; more numerous white flowers; and standard petals with a purple ring surrounding a bright yellow nectar patch. [ABSTRACT FROM AUTHOR]

The name Albuca caudata Jacq. has been widely misunderstood or even ignored since its description in 1791. After studying herbarium specimens and living populations in South Africa, plants fitting Jacquin's concept of that species are found to be widely distributed in the Eastern Cape, mainly in the Albany centre of Endemism. Furthermore, some divergent specimens matching Baker's concept of A. caudata are described as a new related species: A. bakeri. Data on typification, morphology, ecology, and distribution are reported for both taxa. Affinities and divergences with other close allies are also discussed. [ABSTRACT FROM AUTHOR]

The taxonomic treatment for the grasses of southern Africa was one of the first to be based on computerised data and the DELTA system. These data, based on over 70,000 herbarium records, are amenable for analysis of species parameters including abundance, frequency and distribution. This information is suitable for the allocation of species into the seven categories of rarity proposed by Rabinowitz using a combination of habitat specificity ("Narrow" or "Broad"), population structure ("Sparse" or "Abundant") and distribution ("Restricted" or "Widespread"). We compare the species lists obtained for each combination of these three aspects to published Red Data Lists (RDLs) for southern and South Africa. Ninety-three species are placed in the most sensitive or potentially threatened category (Narrow habitat, Sparse populations and Restricted distributions; RSN). This is substantially more than the number of species listed in current RDLs for the region. Chi-square tests indicate a statistically significant bias in taxa from the Fynbos Biome for three of the categories (RSN, RAN and WSN), from the Savanna Biome for the WAN category and from the arid Succulent Karoo and Desert Biomes for the RAB category. Analyses of habitat requirements indicate that many grasses listed (especially those associated with a "Narrow" habitat) are found in some form of wetlands (ephemeral or permanent), especially those at higher altitudes (montane). Despite concerns about the subjective nature in determining the boundaries between the categories, this method is shown to provide a meaningful and valuable list of taxa that require prioritisation for more detailed assessment according to the IUCN criteria. [ABSTRACT FROM AUTHOR]

Arctotis debensis R.J.McKenzie, a new species from the Albany Centre of Floristic Endemism, South Africa, is described and illustrated. It grows almost exclusively in grassland on kommetjies, a distinctive landform of depressions and mounds associated with giant earthworms, in a restricted area west of King William’s Town, Eastern Cape Province. It is the first plant taxon reported to be endemic or near-endemic to this unusual habitat. The new species appears to have been collected rarely and previous collections examined have remained undetermined to species level. The new species is distinguished from closely allied species by the combination of its usually larger dimensions in all parts, prostrate habit, coriaceous leaves that are green, scabrous, and eglandular on the adaxial surface and densely lanate on the abaxial surface, and involucral-bract morphology. © 2006 The Linnean Society of London, Botanical Journal of the Linnean Society, 2006, 151, 581–588. [ABSTRACT FROM AUTHOR]

Of the 90-95 species included in the Rytidosperma clade of grasses (Danthonioideae: Poaceae) about 20 are native to southern Africa, most of these belonging to the genera Karroochloa, Schismus and Tribolium. Whereas morphological data identify all three genera as being monophyletic, the robustness of this pattern is compromised by high levels of homoplasy. Here we use molecular data (plastid trnL-trnF and nuclear ITS sequences) to re-evaluate phylogenetic relationships within the Rytidosperma clade, with the specific aim of testing the monophyly of the African genera. Separate parsimony analyses of the two partitions reveal low levels of incongruence, which may be attributable to incomplete lineage sorting or past hybridization. Analyses of the combined data produce well resolved, strongly supported topologies that are virtually identical, regardless of the inference method used (parsimony or Bayesian inference) or whether or not "conflict" taxa are included. Our data support the monophyly of the Rytidosperma clade (synapomorphies include a punctate-ovate hilum, a large embryo, and lodicule microhairs) as well as the monophyly of the Australasian-South American Rytidosperma s.l. However, the monophyly of Karroochloa, Schismus and Tribolium is strongly contradicted, all three genera being polyphyletic as currently defined. Although not implemented here, a minimum of five new combinations would be required to rectify this situation. Character reconstructions reveal extensive convergence in a number of morphological features, especially those previously used to define genera. We suggest that the convergent pattern of evolution displayed by these traits, most of which describe spikelet/diaspore morphology, is linked to their functionality in seed dispersal and burial, and that this has compromised their utility as phylogenetic markers. [ABSTRACT FROM AUTHOR]

Some plant species possess structures known as leaf domatia, which house mites. The association between domatia-bearing plants and mites has been proposed to be mutualistic, and has been found to be important in species of economic value, such as grapes, cotton, avocado and coffee. This is because leaf domatia affect the distribution, diversity and abundance of predatory and mycophagous mites found on the leaf surface. As a result, plants are thought to benefit from increased defence against pathogens and small arthropod herbivores. This study assesses the relative diversity and composition of mites on an economically important plant host (Coffea aribica) in comparison to mites found in a neighbouring indigenous forest in South Africa. Our results showed that the coffee plantations were associated with only predatory mites, some of which are indigenous to South Africa. This indicates that coffee plantations are able to be successfully colonised by indigenous beneficial mites. We also found an "edge effect", in that coffee trees at the edge of the plantation hosted fewer mite species. These results are a snap-shot from a single sampling period. Nonetheless, they highlight the potential importance of this mutualism in commercial crop species and the possible role of faunal exchanges between indigenous and exotic crop species. This study expands our understanding of the mite–plant mutualism in Southern Africa, a region where acarological studies are sparse. [ABSTRACT FROM AUTHOR]

Abstract: The angiosperm family Proteaceae is a distinct component of the Cape Floristic Region biodiversity hotspot with 330 endemic species. Phylogenetic analyses of subfamily Proteoideae using sequence data from one nuclear and six plastid loci show that most of this diversity is contained in two distinct Cape floral clades. Molecular dating analyses, using Bayesian and penalized likelihood methods and four phylogenetically supported fossil age constraints, reveal contrasting histories for these two clades. The genus Protea belongs to a lineage that may have been in Africa since the Late Cretaceous but began to diversify in the Cape only 5–18Myr ago. In contrast, the Leucadendrinae clade presumably arrived in the region no earlier than 46Myr ago by long-distance dispersal from an Australian ancestor and the extant members of this clade began to diversify in the Cape 22–39Myr ago. These results join a growing number of case studies that challenge the commonly accepted view that most of the Cape flora radiated synchronously in the Late Miocene and Early Pliocene when a Mediterranean climate settled in the region. [Copyright &y& Elsevier]

The article presents a study on the morphology of Albuca (A.) bifolia or Baker. The study involves an extensive field work on the revision of the genus Albuca L. in Grahamstown, South Africa. The result shows that Albuca anisocrispa and A. pseudobifolia are closely related to A. bifolia in terms of floral, vegetative, chronological, and ecological data.

Background: When genetic structure is identified using mitochondrial DNA (mtDNA), but no structure is identified using biparentally-inherited nuclear DNA, the discordance is often attributed to differences in dispersal potential between the sexes., Results: We sampled the intertidal rocky shore mussel Perna perna in a South African bay and along the nearby open coast, and sequenced maternally-inherited mtDNA (there is no evidence for paternally-inherited mtDNA in this species) and a biparentally-inherited marker. By treating males and females as different populations, we identified significant genetic structure on the basis of mtDNA data in the females only., Conclusions: This is the first study to report sex-specific differences in genetic structure based on matrilineally-inherited mtDNA in a passively dispersing species that lacks social structure or sexual dimorphism. The observed pattern most likely stems from females being more vulnerable to selection in habitats from which they did not originate, which also manifests itself in a male-biased sex ratio. Our results have three important implications for the interpretation of population genetic data. First, even when mtDNA is inherited exclusively in the female line, it also contains information about males. For that reason, using it to identify sex-specific differences in genetic structure by contrasting it with biparentally-inherited markers is problematic. Second, the fact that sex-specific differences were found in a passively dispersing species in which sex-biased dispersal is unlikely highlights the fact that significant genetic structure is not necessarily a function of low dispersal potential or physical barriers. Third, even though mtDNA is typically used to study historical demographic processes, it also contains information about contemporary processes. Higher survival rates of males in non-native habitats can erase the genetic structure present in their mothers within a single generation.

Background: The southern African tick shell, Nassarius kraussianus (Dunker, 1846), has been identified as being the earliest known ornamental object used by human beings. Shell beads dated from approximately 75,000 years ago (Pleistocene era) were found in a cave located on South Africa's south coast. Beads made from N. kraussianus shells have also been found in deposits in this region dating from the beginning of the Holocene era (<10,000 years ago). These younger shells were significantly smaller, a phenomenon that has been attributed to a change in human preference., Methodology/principal Findings: We investigated two alternative hypotheses explaining the difference in shell size: a) N. kraussianus comprises at least two genetic lineages that differ in size; b) the difference in shell size is due to phenotypic plasticity and is a function of environmental conditions. To test these hypotheses, we first reconstructed the species' phylogeographic history, and second, we measured the shell sizes of extant individuals throughout South Africa. Although two genetic lineages were identified, the sharing of haplotypes between these suggests that there is no genetic basis for the size differences. Extant individuals from the cool temperate west coast had significantly larger shells than populations in the remainder of the country, suggesting that N. kraussianus grows to a larger size in colder water., Conclusion/significance: The decrease in fossil shell size from Pleistocene to Holocene was likely due to increased temperatures as a result of climate change at the beginning of the present interglacial period. We hypothesise that the sizes of N. kraussianus fossil shells can therefore serve as indicators of the climatic conditions that were prevalent in a particular region at the time when they were deposited. Moreover, N. kraussianus could serve as a biomonitor to study the impacts of future climate change on coastal biota in southern Africa.