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Cotula is a large genus of ca. 50 species, centred in the Cape Floristic Region of South Africa, but also extending into tropical Africa, Eurasia, Australia as well as the Americas. The urgent need for a taxonomic treatment of Cotula has long been acknowledged, with no formal revision available. To this end, a taxonomic revision of the Cotula turbinata group is presented here. Several of the species in this group have previously been treated under the segregate genus Cenia , which included both radiate and disciform species with apically swollen peduncles. The species within the C. turbinata group are however not truly radiate, but rather pseudo-radiate due to modified outer disc florets with a greatly enlarged dorsal lobe. These modified disc florets, or pseudo-rays, are unique to the C. turbinata group and to our knowledge within the tribe. At the beginning of this study three species were recognized, all occurring in the Greater Cape Floristic Region. Extensive herbarium and field studies have revealed the presence of an additional three species, two described here as new (Cotula calcicola Jakoet, Mucina & Magee and Cotula perennans Jakoet, Mucina & Magee) and a third re-instated from the synonymy, Cotula pruinosa (E.Mey. ex. DC.) Jakoet & Magee. As such we here recognize six species, distinguished by their life history, leaf dissection, floret lobe color and size, and cypsela morphology. • Heads not truly radiate but rather pseudo-radiate. • Outer disc florets modified with a greatly enlarged dorsal lobe. • Six species recognized. • Two new species described (Cotula calcicola Jakoet, Mucina & Magee and Cotula perennans Jakoet, Mucina & Magee). • Cotula pruinosa (E. Mey ex. DC.) Jakoet & Magee re-instated from synonymy and new combination provided. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a hierarchical system of forest communities of Mpumalanga Province (South Africa) compatible with the existing South African National Forest Classification (NFC). It describes and interprets floristic and physiognomic differences between the communities and the relevant higher-rank vegetation unit. A total of 434 relevés (rectangular plots, each 0.04ha; listing all species in the plots in Braun-Blanquet cover-abundance scale), sharing 619 species, served as the basis of the classification. The data were classified using the Flexible beta clustering (β=−0.25) in combination with the Bray–Curtis similarity measure. The proposed forest subtypes are described in terms of dominant plant families and genera, growth forms, seasonality or leaf retention characteristics, and the proportion of forest dependent species. Fourteen forest subtypes are distinguished within three national forest types, with no subtypes being recognised within the Lowveld Riverine Forest Type. We propose that the Wakkerstroom Midlands Forest Subtype be embedded within the Northern Highveld Forest Type, and not the Low Escarpment Mistbelt Forest Type as is currently recognised in the NFC. A total of 125 plant families and 375 genera were identified to occur in the Mpumalanga forests, with the most abundant species per family being Rubiaceae, Fabaceae, Celastraceae, Orchidaceae, Euphorbiaceae and Aspleniaceae. 76% of all forest plant species were obligate forest species and 80% of all tree cover is evergreen. [Copyright &y& Elsevier]

Abstract: Cotula sericea L.f. was based on an unlocalised collection from the southwestern Cape of a species with conspicuously petiolate, palmately bipinnatisect leaves and long, leafless scapes with discoid capitula subtended by glabrous, uninerved involucral bracts. It has, however, been historically misapplied to plants from the southern and southeastern South African coast with the leaves extending onto the base of the apically inflated peduncle and with shortly radiate capitula and ovate, ±trinerved bracts. The nomenclatural and taxonomic history of the species is clarified and a lectoype is designated. True C. sericea is a high altitude, local endemic restricted to a few mountains in the Cold Bokkeveld of Western Cape, and we provide a full description and illustration based on wild-collected material. We conclude that it is an older name for the mysterious Cotula fallax D.J.N.Hind, recently described from cultivated material of unknown but possibly South African origin, and which we accordingly place in synonomy. The name Cenia discolor DC. is available for the heterogamous coastal taxon and we make the new combination Cotula discolor (DC.) J.C. Manning & Mucina for it in Cotula. Finally, we conclude that the poorly known Cotula mariae Bremer & Humphries from Cape Recief, Port Elizabeth, is an extreme maritime form of Cotula discolor and reduce it to synonomy. [Copyright &y& Elsevier]

The Cape Fynbos region of South Africa, a global biodiversity hotspot, hosted a diverse large mammal fauna till shortly after permanent European settlement (1652). How these animals survived in this exceptionally nutrient-poor environment is puzzling and it is generally believed that they restricted their movements to the more fertile shale areas. We tested the hypothesis that large herbivores avoid nutrient-poor limestone and sandstone fynbos shrublands in favour of shale-derived renosterveld vegetation using strontium (Sr) isotope analysis. If this technique could reconstruct the preferred feeding habitats of the contemporary fauna, it might also be useful for reconstructing the preferred feeding grounds of an extinct fauna. Using the assumption that small rodents have spatially restricted foraging activities, we determined the Sr/Sr isotope ratios of rodent teeth to establish the isotopic signal characteristic of the different geological substrates in the area. We then analysed Sr/Sr isotope ratios in the bones of a number of different large herbivores found in De Hoop Nature Reserve using laser ablation multi-collector inductively coupled plasma mass spectrometry. These values were compared to the bioavailable (rodent) values on the respective geological substrates. The technique identified differences in feeding substrate selection between different species and groups of the same species. The results also showed that shale renosterveld shrubland is not the exclusive source of nutrition for the large herbivores. Strikingly different isotope ratios among individuals in some populations pointed to significant dispersal events from distant sources. However, we were unable to pinpoint the exact feeding areas using Sr isotope analysis probably because some animals use a combination of substrates for feeding and because the geology of the study area is complex with graded isotope signals. We suggest that this technique is a valuable additional tool for exploring large mammal foraging behaviour on habitats associated with contrasting and less complex geology. [ABSTRACT FROM AUTHOR]

Question: How can vegetation gradients be described in riparian zones located in a species-rich mountain range and how do these gradients explain the variation found in the vegetation? Location: Hottentots Holland Mountains, Western Cape, South Africa. Methods: Three gradients (geographic, longitudinal, lateral) were defined to describe the complex vegetation patterns found here. The gradients are related as follows: (1) the geographic gradient: related to the climatic and topographical changes across the entire mountain range; (2) the longitudinal gradient related to the changes along the different river reaches; (3) the lateral gradient related to the processes along the profile of the riverbed. These three gradients operated on three different hierarchical levels. Partial Canonical Correspondence Analysis (pCCA) was used to determine the amount of variation that is explained on each of the hierarchical levels. Results: The geographical gradient explained the highest fraction (more than 50%) of the total variation explained. This can be ascribed to the high species turnover across landscapes in the Fynbos Biome; this is most likely an outcome that is specific for this region. The second most important gradient was the lateral gradient, which reflects stream power and inundation frequencies of the river. This gradient is represented by ca. 48% of the explained variation and this gradient explains the major disturbances occurring in a riverine ecosystem. The longitudinal gradient was the least important of the gradients and shows overlap with the geographical gradient. Conclusions: In the species-rich environment of the Fynbos Biome geographical factors do not only account for variation in zonal vegetation but also for variation within azonal vegetation, like riparian corridors. [ABSTRACT FROM AUTHOR]

This paper assesses Acocks' veld types against a reclassification of his own data for the Nama-karoo using a suite of multivariate techniques. The analysis showed that the vegetation of Nama-karoo can be partitioned into three major clusters with the most clearly defined cluster corresponding to areas in the arid northwest. Within these clusters the species groups or pools substantiated a number of Acocks' veld types and some of their subdivisions. Notable in this regard are the veld types Orange River Broken Veld and Arid Karoo as well as some of their subdivisions, The findings suggest that some of these subdivisions could well have been raised to full veld type status. Also confirmed was the nebulous nature of Central Upper Karoo and False Arid Karoo with gradual transitions to most neighbouring veld types. Not supported by the analysis are False Succulent Karoo and several veld types, or parts of veld types in the south-eastern Nama-karoo. Non-coincidence with the units of the numerical analysis in the latter area may also be a consequence of a mismatch between Acocks' large sample areas and his relatively fine mapping scale in this particular region. [ABSTRACT FROM AUTHOR]

• Seven species recognized. • One new species described (Cotula tuberculata Jakoet & Magee). • Cotula melaleuca Bolus is here reduced into synonymy with C. barbata DC. • C. leptalea DC. and C. tenella E Mey ex DC. are here reduced into synonymy with C. laxa DC. • Detailed morphological descriptions, typification, illustrations of diagnostic characters and distribution maps indicating the known geographical ranges of these species are included. A taxonomic revision of the Cotula barbata group is presented. At the onset of the study nine species were recognised within this group, which is defined by a combination of an annual life history, usually homogamous discoid capitula, mostly basal leaves that are not sheathing at the base, and naked peduncles that are not inflated apically. These species are restricted to the Greater Cape Floristic Region of South Africa. The species are variable in cypselae morphology, which is shown herein to be taxonomically informative. Through extensive investigation, we here recognize seven species, one of which is described as new. Cotula melaleuca Bolus is reduced into synonymy with C. barbata DC. , C. leptalea DC. and C. tenella E Mey ex DC. are reduced into synonymy with C. laxa DC., and C. tuberculata Jakoet & Magee is described as new. An identification key is provided for the seven species, with detailed morphological descriptions, typification, illustrations of diagnostic characters and distribution maps. [ABSTRACT FROM AUTHOR]

Abstract: The exceptionally high plant diversity in the Cape region of southern Africa continues to attract considerable attention. In a recent paper Linder et al. (2010) concluded that diversification has been promoted by the physical complexity of the Cape environment and by certain biotic interactions, such as those between bees and flowering plants. Although these authors acknowledge the potential role of seed dispersal by ants, they suggested that there were no tests which would demonstrate whether rates of diversification were higher in myrmecochorous lineages versus those with other biotic or abiotic dispersal mechanisms. Here we argue that a set of recent papers by Dunn et al. (2007) and Lengyel et al. (2009, 2010) provide compelling evidence that myrmecochory may have resulted in a doubling of plant diversification, largely due to the greater likelihood of genetic isolation and also of the increased survival rate of plants possessing this dispersal mode. Here, we suggest that myrmecochory, which may be favoured in low nutrient soils, could be a key contributor to the high floristic biodiversity in the Cape region, as well as in other old, climatically stable landscapes such as those of southwest Australia. [Copyright &y& Elsevier]

Describes the establishment and implementation of a national vegetation database in South Africa. Nature of vegetation data; Information on the National Vegetation Database; Tasks of the database.

Abstract: Two new species of Gazania Gaert. (Asteraceae, tribe Arctotideae) from the Greater Cape Floristic Region of South Africa are described. Gazania lanata Magee & Boatwr., a local endemic of dolomite lenses near Robertson, is distinguished by the spatulate to sublyrate, simple or weakly pinnatilobed leaves, the bristle-like hairs along the inflorescence and the densely lanate vestiture of the young growth and involucre. Gazania splendidissima Mucina, Magee & Boatwr. from the arid Namaqualand coast between Port Nolloth and Hondeklipbaai, is distinguished by the suffrutescent habit, semi-succulent leaves with a densely mealy uppermost surface, and prominently maculate involucre. An updated key to the now 18 recognised Gazania species is provided to facilitate identification of these and existing taxa in the genus. [ABSTRACT FROM AUTHOR]

Abstract: Despite the Roggeveldberge comprising the montane heart of the celebrated Hantam–Roggeveld Centre of Plant Endemism (HRC), this section of the southern Great Escarpment in South Africa is botanically poorly known. A detailed physical, historical and phytogeographical overview of the Roggeveldberge is thus presented, and a checklist of 513 plant taxa is provided as a contribution towards a more complete flora for the Roggeveld–Komsberg Escarpment. The HRC is considered in detail, including various delimitations, and all species purported to be endemic to the HRC are reviewed and separated into actual endemics, near-endemics and species incorrectly considered as endemic. [ABSTRACT FROM AUTHOR]

Abstract: The Nuweveldberge forms the central and most arid component to the southern Great Escarpment in South Africa. Situated between the Sneeuberg in the east and the Hantam–Roggeveld in the west, the Nuweveldberge has elements of both the Succulent Karoo and Grassland Biomes. The Nuweveldberge has low endemism (0.5%) compared to the adjacent Sneeuberg (2.3%) and Roggeveldberge (ca. 8%). Following an extensive floristic survey of the Nuweveldberge, a contribution of 473 taxa is provided. Together with the flora by for the Karoo National Park this provides a total flora of 1139 taxa for the Nuweveldberge. Numerous range extensions of (previous) Sneeuberg endemics and Drakensberg near-endemics onto the Nuweveldberge are recorded. Although the Nuweveldberge may have been a corridor facilitating the movement of species from the Cape Floristic Region via the Komsberg through the Nuweveldberge onto the Sneeuberg (and of Drakensberg elements westwards from the Sneeuberg) there is currently little evidence of such connectivity. This is postulated to be due to aridification of the Nuweveldberge since the Last Glacial Maximum, and also likely explains the low endemism on the Nuweveldberge. [ABSTRACT FROM AUTHOR]

Abstract: The Sneeuberg mountain complex (Eastern Cape) comprises one of the most prominent sections of the Great Escarpment in southern Africa but until now has remained one of the botanically least known regions. The Sneeuberg is a discrete orographical entity, being delimited in the east by the Great Fish River valley, in the west by the Nelspoort Interval, to the south by the Plains of Camdeboo, and to the north by the Great Karoo pediplain. The highest peaks range from 2278 to 2504 m above sea level, and the summit plateaux range from 1800 to 2100 m. Following extensive literature review and a detailed collecting programme, the Sneeuberg is reported here as having a total flora of 1195 species of which 107 (9%) are alien species, 33 (2.8%) are endemic, and 13 (1.1%) near-endemic. Five species previously reported as Drakensberg Alpine Centre (DAC) endemics are now known to occur in the Sneeuberg (representing range extensions of some 300–500 km). One-hundred-and-five species (8.8%) are DAC near-endemics, with the Sneeuberg being the western limit for most of these. Ten species (0.8%) represent disjunctions across the Karoo Interval from the Cape Floristic Region (CFR) to the Sneeuberg. In all, some 23 significant range extensions, eight new species, and several rediscoveries are recorded. We conclude by recognising the Sneeuberg as a new centre of endemism along the Great Escarpment, with floristic affinities with the Albany Centre and the DAC, and links to the CFR. [Copyright &y& Elsevier]

Plant community composition and distribution on and off isolated mesas were investigated across Nama Karoo communities in the Eastern Cape, South Africa. Species composition and cover were measured in plots along a transect extending from the SE plains and slopes, across the plateaux, onto the NW slopes and plains of three mesas (Tafelberg, Foiminkskop and Buffelskop). Data were then classified using the floristic-sociological approach, assisted by the computer package TWINSPAN. Canonical Correlation Analysis was used to analyse the relationship between vegetation and environmental patterns. Mesa communities were found to be distinctly different from plains communities, with no shared communities between the two habitats. The distribution of communities across the landscape is attributed to a soil-moisture gradient. Differences in habitat probably existed before the impact of domestic livestock, but overgrazing has likely exacerbated the differences. The potential to use mesas as sources of seeds and propagules for the surrounding degraded plains is low, since few species are shared between the two habitats. However, generalist, palatable species such as Felicia muricata, Eragrostis obtusa, Pentzia incana etc. could have some potential for future restoration. Dolerite-capped mesas such as Tafelberg and Folminkskop had a general slope community shared between the two mesas. Aspect and the expected cooler, more moist conditions on SE slopes as factors determining community composition for the dolerite mesas were overridden by soil type and associated nutrient status. In xeric sandstone mesas such as Buffelskop, soil type and associated nutrient status were overridden by aspect and slope as determinants of community composition. Mesa habitats are generally not grazed heavily by livestock due to their inaccessible nature, and are not threatened by current land use practices. Plains habitats are often degraded, a consequence of 200 years of selective grazing. [ABSTRACT FROM AUTHOR]

Received 2 July 1999; revised 5 October 1999The aim of this paper is to identify, classify and describe plant communities on abandoned, formerly cultivated, old fields in the former Transkei (Eastern Cape Province) and to derive hypothetical succession pathways. Forty two releves, made in representative areas with abundant old-field lots, were classified and ordinated using standard methods of numerical vegetation data analysis. Three new associations were recognised, namely the Richardio brasiliensis-Eragrostietum planae, the Trichoneuro grandiglumis-Aristidetum congestae and the Tageto minutae-Cynodontetum dactyli. Within the Tageto minutae-Cynodontetum dactyli, two new sub-associations were recognised, namely cyperetosum esculenti and typicum. The most important coenocline spanning the young Tageto minutae-Cynodontetum dactyli and the old Richardio brasiliensis-Eragrostietum planae, correlated with the age of old-fields. We postulate that this coenocline might represent the main succession trend within the mesic old fields in Transkei. The Trichoneuro grandiglumis-Aristidetum congestae characteristic of dry sandy soils does not participate in this cline.Keywords: abandoned land, associations, ordination, plant communities, succession syntaxa. [ABSTRACT FROM AUTHOR]

The role of intraspecific trait variability is increasingly recognized as a key factor shaping plant fitness and community assembly worldwide. Studying the direct effects of habitat heterogeneity on trait expression of individual plants of the same species is a useful tool to quantify intraspecific trait variability locally. We investigated how habitat heterogeneity on granite inselbergs affected intraspecific trait variability of 19 functional traits in three shrub species of the family Proteaceae in south western Australia, a global biodiversity hotspot. We used pairwise comparison (single trait) and multivariate analysis (multiple traits, functional space) to detect shifts in trait patterns. Consistent with our predictions, we found that individuals developing in putatively more stressful habitats (highly sun-irradiated, shallow-soil patches on the outcrops) were characterized by trait expressions indicative of more conservative resource-related strategies when compared with plants occurring in the surrounding woodlands that were experiencing more benign ecological conditions. These results were significant for two out of three species. Granite inselbergs promoted plant longevity, a signal that these granite inselbergs might offer refugial conditions defined as protection against fire. [ABSTRACT FROM AUTHOR]

Aim Granite outcrops are prominent throughout the world and harbour many endemic species. Their topographic complexity and range of environments have led to the hypothesis that they act as refugia facilitating the persistence of species through climate change. We evaluate this hypothesis by investigating the phylogeographic patterns in a common granite endemic shrub. Location Granite outcrops of the Southwest Australian Floristic Region. Methods Chloroplast haplotypes of 89 Kunzea pulchella individuals from 16 granite outcrops were determined from sequences of three chloroplast intergenic spacer regions. Phylogenetic reconstruction and divergence dating was inferred using Bayesian and Parsimony analyses and phylogenetic relationships between haplotypes were examined in relation to geographic distributions. Nuclear diversity and differentiation of populations were assessed through analysis of 11 nuclear microsatellite loci across 384 individuals from the 16 granite outcrops. Results Kunzea pulchella exhibited low haplotype and allelic diversity within outcrops and high levels of divergence among outcrops, indicating an ancient restriction to specific outcrops with genetic drift as the main driver of evolution. Two divergent lineages were revealed in the chloroplast phylogeny dating to the Pliocene and potentially reflecting the initial impact of increased aridity prior to isolation on individual outcrops. Main conclusions Rather than uncovering the typical pattern for Pleistocene refugia with contraction to, and expansion from particular granite outcrops, we observed persistence, prolonged isolation and divergence of populations. We suggest the persistence of K. pulchella on multiple outcrops through a period of considerable climatic change may be a result of broad climatic tolerances or contraction and expansion dynamics operating at microrefugial scales within outcrops. Our observations of low haplotype and allelic diversity within populations of K. pulchella provide some support for the latter. The enduring nature of K. pulchella and evolutionary potential of populations on individual outcrops accentuates the value of these environments for biodiversity conservation planning in a changing climate. [ABSTRACT FROM AUTHOR]

Abstract: The Boschberg and Groot-Bruintjieshoogde form the wettest and floristically most distinct section of the Sneeuberg mountain complex. As such they warrant a separate detailed investigation, particularly in terms of their connectivity between the main Sneeuberg in the west, the Great Winterberg–Amatolas in the east, and with the Cape Floristic Region (CFR) to the south and south-west. Following a detailed botanical investigation and overview we conclude that the Boschberg and Groot-Bruintjieshoogde are a floristic hub between the CFR and southern Great Escarpment, as well as between the moister eastern and drier western components of the Great Escarpment. Our data confirm that the Boschberg forms part of the south-eastern connection between the CFR and the Afromontane region in southern Africa, a connection first suggested by . [ABSTRACT FROM AUTHOR]

Abstract: Accessions of Pennisetum purpureum in agricultural research centres in sub-Saharan Africa were genotyped using Amplified Fragment Length Polymorphisms (AFLPs) using primer combinations MluI/MseI. Cluster analyses of resulting bands suggested that the samples could be grouped into five large and five small-sized clusters. Principal coordinate analysis revealed two major clusters being well separated, with bulk of the samples forming one, poorly structured cluster. Our analyses failed to reveal the regional groupings found in previous studies using a subset of our sample universe and based on RAPDs as well as morphological and agronomical data. The inability of the AFLP data to clearly demarcate accessions is ascribed to either the presence of high levels of genetic uniformity, or non-optimal primers and/or bad germplasm management practices. The re-registration of all accessions, based on DNA barcoding, is suggested as a means to resolve the lingering problems regarding the identity of accessions. [Copyright &y& Elsevier]