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This paper assesses progress towards the control of biological invasions in 18 protected areas (PAs) covering 677 584 ha in the Cape Floristic Region (CFR), and whether progress has been sufficient to achieve Target 6 of the Kunming-Montreal Global Biodiversity Framework. We used eight indicators for assessing the inputs (quality of the regulatory framework, money spent and planning coverage for species and protected areas), outputs (species and protected areas treated), and outcomes (effectiveness of species and protected area treatments) of management. The estimated money spent over 13 years (2010–2022) was ZAR 976 million, or ZAR 75 million per year. Management plans for PAs were assessed as adequate over 78.5% of the area, but only six out of 226 regulated invasive species had species-specific control plans in place. A total of 567 alien species occurred in the CFR’s PAs, 226 of which were regulated species (i.e. species that had to be controlled), 126 (55.8%) of which received some management. Spending was highly skewed, with over 60% of all funding spent on trees and shrubs in the genus Acacia. Management efforts reached 24% of the land within the CFR’s protected areas, with higher coverage in national parks (60%) than in provincial nature reserves (9%). Management effectiveness was assessed as either permanent, effective or partially effective for 29 species (20 due to biological control), and ineffective for 25; for the remainder, there was either no management or effectiveness could not be evaluated. We conclude that some progress has been made with respect to controlling invasive alien species in the CFR, but that insufficient and declining funding remains a significant barrier to effective management. To increase efficiency, it will be necessary to secure additional funding from more diversified sources, make more use of biological control and prescribed fire, and regularly monitor the outcomes of management. [ABSTRACT FROM AUTHOR]

Simple Summary: Pollen from angiosperms can have extremely resistant walls that are often preserved as fossils and reflect ancient plants that lived on Earth millions of years ago. We discovered fossil pollen of Hyaenanche (Picrodendraceae) in a ca. 37-million-year-old palynoflora from Kenya. Today, Hyaenanche is endemic to a small part of the Cape Province, South Africa, where the plants grow on rocky substrate under a dry climate as part of bush vegetation. The Kenyan fossils show that Hyaenanche had a much wider distribution in Africa before the present, and compared to other fossil counterparts, we believe that the genus dispersed from Europe into Africa already prior to this earliest record now discovered. The associated fossil pollen and other Hyaenanche and alike records suggest that the plants occurred in complex forest environments, enduring fully humid climates in the past. Therefore, our study shows that relying on the closest living or potential modern analogue of a fossil taxon is not always the most representative. This applies especially to relict taxa. For the paleoecological estimations of such fossil plants, their complete fossil records, associated plant taxa from the same fossil assemblages, as well as present day closely related genera need to be considered. On the African continent, Picrodendraceae are represented by four genera. Their intracontinental paleophytogeographic histories and paleoecological aspects are obscured by the lack of pre-Miocene fossils. For this study, late Eocene sediments from Kenya were investigated. The sample was prepared in the laboratory, and its organic residue was screened for pollen. We extracted fossil Picrodendraceae pollen and investigated the grains using light and scanning electron microscopy. Based on the pollen morphology, the grains were assigned to Hyaenanche. This genus is currently confined to a small area within the Cape Province, South Africa. There, the plants grow as shrubs and small trees at an elevation between 60 and 800 m, on rocky substrate, as part of open fynbos vegetation, and under a dry climate with hot summers and limited precipitation. The sedimentary context and the associated palynoflora suggest that during the Eocene of Kenya, Hyaenanche was part of lowland coastal vegetation in Eastern Africa. There, the plants grew under fully humid to winter-dry tropical climates as part of landwards margins of mangroves, seasonally inundated floodplain forests, or coastal forests. Our study shows that when evaluating paleoecological aspects of relict monotypic plants, their extant closely related genera and their fossil records need to be considered. [ABSTRACT FROM AUTHOR]

Premise: Southern Africa is a biodiversity hotspot rich in endemic plants and lichen‐forming fungi. However, species‐level data about lichen photobionts in this region are minimal. We focused on Trebouxia (Chlorophyta), the most common lichen photobiont, to understand how southern African species fit into the global biodiversity of this genus and are distributed across biomes and mycobiont partners. Methods: We sequenced Trebouxia nuclear ribosomal ITS and rbcL of 139 lichen thalli from diverse biomes in South Africa and Namibia. Global Trebouxia phylogenies incorporating these new data were inferred with a maximum likelihood approach. Trebouxia biodiversity, biogeography, and mycobiont–photobiont associations were assessed in phylogenetic and ecological network frameworks. Results: An estimated 43 putative Trebouxia species were found across the region, including seven potentially endemic species. Only five clades represent formally described species: T. arboricola s.l. (A13), T. cf. cretacea (A01), T. incrustata (A06), T. lynniae (A39), and T. maresiae (A46). Potential endemic species were not significantly associated with the Greater Cape Floristic Region or desert. Trebouxia species occurred frequently across multiple biomes. Annual precipitation, but not precipitation seasonality, was significant in explaining variation in Trebouxia communities. Consistent with other studies of lichen photobionts, the Trebouxia–mycobiont network had an anti‐nested structure. Conclusions: Depending on the metric used, ca. 20–30% of global Trebouxia biodiversity occurs in southern Africa, including many species yet to be described. With a classification scheme for Trebouxia now well established, tree‐based approaches are preferable over "barcode gap" methods for delimiting new species. [ABSTRACT FROM AUTHOR]

Summary: Plants employ a diversity of reproductive safeguarding strategies to circumvent the challenge of pollen limitation. Focusing on southern African Lachenalia (Asparagaceae: Scilloideae), we test the hypothesis that the evolution of reproductive safeguarding traits (self‐compatibility, autonomous selfing, bird pollination and clonal propagation) is favoured in species occupying conditions of low insect abundance imposed by critically infertile fynbos heathland vegetation and by flowering outside the austral spring insect abundance peak.We trace the evolution of these traits and selective regimes on a dated, multi‐locus phylogeny of Lachenalia and assess their evolutionary associations using ordinary and phylogenetic regression.Ancestral state reconstructions identify an association with non‐fynbos vegetation and spring flowering as ancestral in Lachenalia, the transition to fynbos vegetation and non‐spring flowering taking place multiple times. They also show that self‐compatibility, autofertility, bird pollination and production of multiple clonal offsets have evolved repeatedly.Regression models suggest that bird pollination and self‐compatibility are selected for in fynbos and in non‐spring flowering lineages, with autofertility being positively associated with non‐spring flowering. These patterns support the interpretation of these traits as reproductive safeguarding adaptations under reduced insect pollinator abundance. We find no evidence to support the interpretation of clonal propagation as a reproductive safeguarding strategy. See also the Commentary on this article by Burd, 244: 7–9. [ABSTRACT FROM AUTHOR]

Background and aims - Following detailed phylogenetic and biogeographic studies of the tribe Psoraleeae, the genus Psoralea L. was shown to have been derived out of Otholobium C.H.Stirt. As Psoralea has nomenclatural priority, Otholobium has been subsumed into Psoralea, whereby two broad subgeneric groups are aligned with the previous descriptions of the separate genera, but some problems of placement of a few species remain unresolved. Work is ongoing to study and describe the nearly 20 undescribed species that will have to be considered before sectional groups can be established. In this paper we describe ten new species, including several putative taxa already recognized in regional floras, based on historic specimens and more recent field collections. Material and methods - Standard practices of herbarium and field taxonomy have been applied to study herbarium material available at B, BLFU, BM, BOL, BR, E, GRA, J, JRAU, K, KEI, L, LE, LINN, M, MO, NBG, NH, NU, NY, OXF, P, PRA, PRC, PRE, PRU, S, SAM, SCHG, SRGH, TCD, Z, ZT, and US. Additional material was provided from fieldwork by the authors and collaborators. Key results - Ten new species of Psoralea from southern Africa are described: Psoralea crista C.H.Stirt. & Muasya, P. fulva C.H.Stirt. & Muasya, P. luteovirens C.H.Stirt. & Muasya, P. nubicola C.H.Stirt. & Muasya, P. oreopola C.H.Stirt., P. pallescens C.H.Stirt. & Muasya, P. papillosa C.H.Stirt. & Muasya, P. prompta C.H.Stirt. & Muasya, P. schutteae C.H.Stirt. & Muasya, and P. vlokii C.H.Stirt. & Muasya. Conclusion - The newly described species, all restricted to South Africa, increases the number of Psoralea species to 129. These species arise from expanded fieldwork into previously under-collected areas, as well as from better refinement in species delimitations in the leafless 'aphylla' and pinnately-leaved species complexes. [ABSTRACT FROM AUTHOR]

Premise: Increases in genome size in plants—often associated with larger, low‐density stomata and greater water‐use efficiency (WUE)—could affect plant ecophysiological and hydraulic function. Variation in plant genome size is often due to polyploidy, having occurred repeatedly in the austral sedge genus Schoenus in the Cape Floristic Region (CFR), while species in the other major schoenoid genus in the region, Tetraria, have smaller genomes. Comparing these genera is useful as they co‐occur at the landscape level, under broadly similar bioclimatic conditions. We hypothesized that CFR Schoenus have greater WUE, with lower maximum stomatal conductance (gwmax) imposed by larger, less‐dense stomata. Methods: We investigated relationships between genome size and stomatal parameters in a phylogenetic context, reconstructing a phylogeny of CFR‐occurring Schoeneae (Cyperaceae). Species' stomatal and functional traits were measured from field‐collected and herbarium specimens. Carbon stable isotopes were used as an index of WUE. Genome size was derived from flow‐cytometric measurements of leafy shoots. Results: Evolutionary regressions demonstrated that stomatal size and density covary with genome size, positively and negatively, respectively, with genome size explaining 72–75% of the variation in stomatal size. Larger‐genomed species had lower gwmax and C:N ratios, particularly in culms. Conclusions: We interpret differences in vegetative physiology between the genera as evidence of more‐conservative strategies in CFR Schoenus compared to the more‐acquisitive Tetraria. Because Schoenus have smaller, reduced leaves, they likely rely more on culm photosynthesis than Tetraria. Across the CFR Schoeneae, ecophysiology correlates with genome size, but confounding sources of trait variation limit inferences about causal relationships between traits. [ABSTRACT FROM AUTHOR]

A new species of the genus Chumma Jocqué, 2001, C. foordi sp. nov., is described from the Western Cape, South Africa. New distribution records for C. bicolor Jocqué & Alderweireldt, 2018, C. foliata Jocqué & Alderweireldt, 2018 and C. gastroperforata Jocqué, 2001 are presented. The genus is recorded from the Northern Cape Province for the first time, extending its range extensively to the northwest by approximately 450 km. The distribution of all Chumma species is mapped. [ABSTRACT FROM AUTHOR]

Lampranthus consists of 85 species of succulent perennials which are all endemic to southern Africa. Most of its species are restricted to fynbos and regenerate in large numbers after fires. We use nine chloroplast markers to generate a phylogeny with a dense sampling of Lampranthus and some taxa which may be closely related to it. While we found that most of the species belong to one strongly supported "core" clade, we also found three minor clades of Lampranthus that fall outside this core. For Lampranthus we set up a new classification of three subgenera. The clades forming L. subg. Adunci (3 spp.) and subg. Calcarati (1 sp.) are unresolved within the Ruschieae and we treat them as subgenera until their relationships are clarified. Three sections are proposed for L. subg. Lampranthus and we also suggest new synonymy for several species in L. sect. Lampranthus (65 spp.) and sect. Blandi (15 spp.). Roosia and the type species for Esterhuysenia are nested in L. sect. Blandi and so these genera are subsumed under Lampranthus. Esterhuysenia stokoei forms part of Lampranthus and is the sole member of a new section within L. subg. Lampranthus. The two larger sections of L. subg. Lampranthus show different evolutionary trends and distributions: Lampranthus sect. Lampranthus contains more species, they are mostly in the winter rainfall region of the Western Cape and they have a greater range of floral shapes and colours. Lampranthus sect. Blandi contains a single species in the Kamiesberg, in the Northern Cape, while most of its species occur along the southern coast of southern Africa eastwards to southern Natal. These species are florally less diverse. Two species of Lampranthus are moved to a new genus, Malephoropsis gen. nov. These are unrelated to the rest of Lampranthus and they fall among species of Malephora, Disphyma and Gibbaeum with which they share softly corky branches, mesomorphic leaves and only slightly woody fruits with false septa. Several species, which were at one stage included in Lampranthus, are re‐instated in Ruschia; for four others, previously transferred out of Lampranthus to Esterhuysenia or Oscularia, but which cannot be accommodated into any of the existing genera, we propose a new genus, Sederbergia gen. nov. Lastly, we consider three monotypic genera which were sequenced here for the first time: Circandra is re‐instated in Erepsia; Malotigena is transferred to Delosperma subg. Proterogyna; the relationships of Daggodora remain unresolved. [ABSTRACT FROM AUTHOR]

This article is a Commentary on Duncan et al. (2024), 244: 307–317. [ABSTRACT FROM AUTHOR]

Background and Aims In many systems, postfire vegetation recovery is characterized by temporal changes in plant species composition and richness. We attribute this to changes in resource availability with time since fire, with the magnitude of species turnover determined by the degree of resource limitation. Here, we test the hypothesis that postfire species turnover in South African fynbos heathland is powered by fire-modulated changes in nutrient availability, with the magnitude of turnover in nutrient-constrained fynbos being greater than in fertile renosterveld shrubland. We also test the hypothesis that floristic overlaps between fynbos and renosterveld are attributable to nutritional augmentation of fynbos soils immediately after fire. Methods We use vegetation survey data from two sites on the Cape Peninsula to compare changes in species richness and composition with time since fire. Key Results Fynbos communities display a clear decline in species richness with time since fire, whereas no such decline is apparent in renosterveld. In fynbos, declining species richness is associated with declines in the richness of plant families having high foliar concentrations of nitrogen, phosphorus and potassium and possessing attributes that are nutritionally costly. In contrast, families that dominate late-succession fynbos possess adaptations for the acquisition and retention of sparse nutrients. At the family level, recently burnt fynbos is compositionally more similar to renosterveld than is mature fynbos. Conclusions Our data suggest that nutritionally driven species turnover contributes significantly to fynbos community richness. We propose that the extremely low baseline fertility of fynbos soils serves to lengthen the nutritional resource axis along which species can differentiate and coexist, thereby providing the opportunity for low-nutrient extremophiles to coexist spatially with species adapted to more fertile soil. This mechanism has the potential to operate in any resource-constrained system in which episodic disturbance affects resource availability. [ABSTRACT FROM AUTHOR]

Invasive flowering plants can disrupt plant–pollinator networks. This is well documented where invasives occur amongst native plants; however, the potential for 'spillover' effects of invasives that form stands in adjacent habitats are less well understood. Here we quantify the impact of two invasive Australian species, Acacia saligna and Acacia longifolia, on the plant–pollinator networks in fynbos habitats in South Africa. We compared networks from replicate 1 ha plots of native vegetation (n = 21) that were subjected to three treatments: (1) at least 400 m from flowering Acacia; (2) adjacent to flowering Acacia, or (3) adjacent to flowering Acacia where all Acacia flowers were manually removed. We found that native flowers adjacent to stands of flowering Acacia received significantly more insect visits, especially from beetles and Apis mellifera capensis, and that visitation was more generalized. We also recorded visitation to, and the seed set of, three native flowering species and found that two received more insect visits, but produced fewer seeds, when adjacent to flowering Acacia. Our research shows that 'spillover' effects of invasive Acacia can lead to significant changes in visitation and seed production of native co-flowering species in neighbouring habitats—a factor to be considered when managing invaded landscapes. [ABSTRACT FROM AUTHOR]

Wetlands harbour a wide range of vital ecosystems. Hence, mapping wetlands is essential to conserving the ecosystems that depend on them. However, the physical nature of wetlands makes fieldwork difficult and potentially erroneous. This study used multispectral UAV aerial photography to map ten wetland plant species in the Fynbos Biome in the Steenbras Nature Reserve. We developed a methodology that used K-Nearest Neighbour (KNN), Support Vector Machine (SVM), and Random Forest (RF) machine learning algorithms to classify ten wetland plant species using the preselected bands and spectral indices. The study identified Normalized green red difference index (NGRDI), Red Green (RG) index, Green, Log Red Edge (LogRE), Normalized Difference Red-Edge (NDRE), Chlorophyll Index Red-Edge (CIRE), Green Ratio Vegetation Index (GRVI), Normalized Difference Water Index (NDWI), Green Normalized Difference Vegetation Index (GNDVI) and Red as pertinent bands and indices for classifying wetland plant species in the Proteaceae, Iridaceae, Restionaceae, Ericaceae, Asteraceae and Cyperaceae families. The classification had an overall accuracy of 87.4% and kappa accuracy of 0.85. Thus, the findings are pertinent to understanding the spectral characteristics of these endemic species. The study demonstrates the potential for UAV-based remote sensing of these endemic species. [ABSTRACT FROM AUTHOR]

Grootbos Nature Reserve falls within the Cape Floristic Region of South Africa and comprises fynbos and forest vegetation elements, which exist as alternate stable states and are naturally maintained by feedbacks between vegetation, fire, topography and climate. The objective of this study was to investigate changes in forest extent in the Baviaansfontein valley in Grootbos Nature Reserve in order to understand whether current forest coverage was greater or lesser prior to colonial settlement. Incorporating paleoecology has the potential to define historical ranges of landscape variability that can guide forest restoration programs that are aligned to historical forest occurrence. Not all landscapes are suited for tree planting initiatives as they harbor indigenous open vegetation, which is of conservation value. Historical and palaeoecological information is especially valuable as tree planting initiatives and reforestation programs are becoming more popular. Here we present a combined palynological (pollen, spores, charcoal) and geochemical approach (X-ray fluorescence elemental ratios, Loss-on-ignition), to evaluate the historic extent and distribution of forest and fynbos vegetation for the past ~250 years at Baviaansfontein in the Grootbos Nature Reserve. The start of the record was dominated by pollen typical of asteraceous fynbos, with evidence of forest elements also present, though in low abundance. After 200 years (c.1750 CE-1950 CE) of increased input of micro- and macrocharcoal, the subsequent decline in charcoal indicates a decrease in fire occurrence. This decline coincides with increased input of forest pollen taxa, suggesting that fire suppression most likely triggered forest expansion and perhaps initiated the beginning of a biome boundary shift. The continued decline in fire promoted the development of the present-day proteoid fynbos type around ~1980 CE and was responsible for the replacement of the previously more asteraceous-dominated fynbos type. The results show that changes in fire occurrence have driven compositional changes over time within fynbos but also contributed to the expansion of forest at the expense of fynbos. Considering the palaeoecological record and the expected warmer climate with more fires, forest expansion at Baviaansfontein is not recommended. The proteoid-dominated fynbos biome might be similarly negatively affected by warmer climate and a shift to an asteraceous fynbos community could occur in the future. [ABSTRACT FROM AUTHOR]

• Eleven new species are described. • New infraspecific combination created for I. pinnata. • All species illustrated in detailed photographic plates. • Conservation assessment and IUCN red list status is recommended for every species. Indigofera sect. Brachypodae DC. is a large group of approximately 40 species within the Cape Clade, mostly restricted to the Core Cape Region (CCR), with only two species extending eastwards to Grahamstown. This section has been subdivided into four subsections based primarily on morphological characters. Subsect. Brachypodae is the most diverse of the four subsections and is characterised by having sclerophyllous leaves, with a distinctly sunken midvein and (usually) revolute leaf margins. This group occurs almost exclusively within Fynbos, with a few species growing in coastal Strandveld vegetation. Revised here, nineteen species are recognized in this subsection, eleven of which are new to science. Additionally, a new infraspecific combination is created for I. pinnata following nomenclatural and identification confusion. All species are formally described here, with photographic plates of each and illustrations of corollas and calyces provided. Many of the new species were either unrecognised at the time of the last revision in Flora Capensis 2, or have only been discovered recently. Distribution maps and information regarding habitat preference, phenology, and ecology and recommended IUCN red list status of each species are also provided. [ABSTRACT FROM AUTHOR]

• Four Aspalathus species new to science are described. • Accounts are provided for three presumed extinct species that were rediscovered. • Detailed photographic plates and distribution maps are included. • Conservation assessments are provided for all seven species. We describe four new species from the Western Cape, South Africa. Aspalathus strigosa Du Preez & C.H.Stirt. is only known by the type collection from the southern slopes of the Klein Swartberg Mountains near Ladismith. Aspalathus albomagnifica Du Preez & C.H.Stirt. is a white-flowered species from lowland renosterveld and fynbos from Hartenbos on the Garden Route. Aspalathus jardinii Du Preez & C.H.Stirt. is a habitat specialist growing in sand dunes of the Riet River running through the Swartruggens Mountains. Aspalathus albicephala Du Preez & C.H.Stirt. is an attractive, critically endangered species from the rooibos belt on Gifberg Mountain. Notes are also provided on three recently rediscovered taxa that were believed to be extinct, Aspalathus cordicarpa R.Dahlgren, A. compacta R.Dahlgren and A. complicata (Benth.) R.Dahlgren. Composite photographic plates, distribution maps, details of habitat, ecology and conservation status are provided for all species. [ABSTRACT FROM AUTHOR]

Fire is central to the Cape Floristic Region's highly biodiverse and disturbance-adapted Fynbos Biome. However, prehistoric fire regimes, their ecological consequences, and their relationships with large-scale climate drivers and human activities remain poorly understood. Here, we use a high-resolution sedimentary charcoal record from Verlorenvlei, a coastal lake situated on the west coast, to interrogate links between fire, climate, and pastoralism in the Fynbos Biome. Our record has a robust chronology supported by 24 radiocarbon dates and provides a continuous sedimentary sequence spanning the last 4200 years, documenting fire activity before and after the local arrival of pastoralists in the Verlorenvlei area ∼1500 cal years BP. Fire at Verlorenvlei over the last 4200 years is variable, with relatively low activity until ∼2000 cal years BP, after which variable but generally higher fire activity occurs until the highest period of fire activity from ∼1450 to 1800 CE (∼500–150 cal years BP). The increase in fire activity ∼2000 years ago corresponds with a shift in the diatom assemblage at Verlorenvlei from marine towards brackish and freshwater species, reflecting increased precipitation derived from a strengthening of the southern westerly winds. The peak in fire activity beginning ∼1450 CE (∼500 cal years BP), near the onset of the Little Ice Age, tracks a second diatom-inferred strengthening of the westerly winds. Other southern hemisphere and Antarctic records further corroborate this increased westerly influence after ∼2000 years. Linear regression modeling on the fire record indicates that moisture availability is the primary driver of fire at Verlorenvlei, with little evidence that human populations influenced fire. Our reconstruction suggests that fire activity at Verlorenvlei is limited by moisture availability and that wetter conditions facilitate increased vegetation (i.e., fuel) and intensified fire at this otherwise fuel-limited site. This work has implications for management and conservation decisions in response to future predictions of a warmer and drier climate along South Africa's west coast.

Grootbos Nature Reserve falls within the Cape Floristic Region of South Africa and comprises fynbos and forest vegetation elements, which exist as alternate stable states and are naturally maintained by feedbacks between vegetation, fire, topography and climate. The objective of this study was to investigate changes in forest extent in the Baviaansfontein valley in Grootbos Nature Reserve in order to understand whether current forest coverage was greater or lesser prior to colonial settlement. Incorporating paleoecology has the potential to define historical ranges of landscape variability that can guide forest restoration programs that are aligned to historical forest occurrence. Not all landscapes are suited for tree planting initiatives as they harbor indigenous open vegetation, which is of conservation value. Historical and palaeoecological information is especially valuable as tree planting initiatives and reforestation programs are becoming more popular. Here we present a combined palynological (pollen, spores, charcoal) and geochemical approach (X-ray fluorescence elemental ratios, Loss-on-ignition), to evaluate the historic extent and distribution of forest and fynbos vegetation for the past ~250 years at Baviaansfontein in the Grootbos Nature Reserve. The start of the record was dominated by pollen typical of asteraceous fynbos, with evidence of forest elements also present, though in low abundance. After 200 years (c.1750 CE–1950 CE) of increased input of micro- and macrocharcoal, the subsequent decline in charcoal indicates a decrease in fire occurrence. This decline coincides with increased input of forest pollen taxa, suggesting that fire suppression most likely triggered forest expansion and perhaps initiated the beginning of a biome boundary shift. The continued decline in fire promoted the development of the present-day proteoid fynbos type around ~1980 CE and was responsible for the replacement of the previously more asteraceous-dominated fynbos type. The results show that changes in fire occurrence have driven compositional changes over time within fynbos but also contributed to the expansion of forest at the expense of fynbos. Considering the palaeoecological record and the expected warmer climate with more fires, forest expansion at Baviaansfontein is not recommended. The proteoid-dominated fynbos biome might be similarly negatively affected by warmer climate and a shift to an asteraceous fynbos community could occur in the future.

Erica comprises ~860 species of evergreen shrubs and trees ranged from Europe to southern Africa and Madagascar. Wood structure of the around 20 European species is well studied, but despite its relevance to adaptation across the wider geographic range, it has not yet been explored across the much greater diversity, particularly of southern African lineages. In this study, we examine wood structure of 28 Erica species from southern Africa. In the African Erica clade, loss of scalariform perforation plates could be driven by increased aridity and seasonality in the mid-Miocene, and its re-gain can represent an adaptation to freezing in the high elevation species E. nubigena. As vessels in Erica are mostly solitary, imperforate tracheary elements probably form a subsidiary conduit network instead of vessel groups. Increase of ray frequency in habitats with a prominent dry and hot season probably facilitates refilling of vessels after embolism caused by water stress. Wider rays are ancestral for the lineage comprising African Erica and the Mediterranean E. australis. The negative correlation between ray width and expression of summer drought is consistent with Ojeda's model explaining the diversification of seeders and resprouters among southern African Erica. [ABSTRACT FROM AUTHOR]

• Four species new to science are described. • Detailed photographic plates and distribution maps are included. • Conservation assessments are provided for all four species. Four new Indigofera species are described from the Greater Cape Floristic Region (GCFR). Indigofera barkeri is a new annual from the Richtersveld, with small flowers, 3.5–4.0 mm long, pinnately trifoliolate leaves and laterally flattened seeds. Indigofera dodii is endemic to the area around Cape Town, growing on granite and shaly slopes. It has apically congested racemes, flowers 6.0–6.5 mm long, digitately trifoliolate leaves, fruit with a hispid indumentum and tuberculate seed testas. Indigofera gariepensis , endemic to dry riverbeds in the eastern Richtersveld, is recognized by its alternate, silky-velutinous leaflets and calyx lobes ± equal in length to its 5.5–6.5 mm long magenta flowers. Indigofera tanquana is known from only two collections and is endemic to the western Tanqua Karoo. It is easily recognized by its broad old grey stems, spinescent branches, simple grey-canescent leaves that aggregate on woody brachyblasts and reddish-magenta flowers. Detailed morphological descriptions are presented with composite photographic plates for each species. Notes on ecology, detailed diagnoses comparing with closely related species, a distribution map and an IUCN red list conservation assessment for each species is also provided. [ABSTRACT FROM AUTHOR]

The Proteaceae, a diverse family of woody flowering plants in the Southern Hemisphere, contains many species known to be susceptible to Phytophthora cinnamomi, both in the natural environment and in cut-flower orchards. Very little is known about the prevalence of P. cinnamomi and other oomycetes across these landscapes. To address this knowledge gap, we used a double ITS1 and RPS10 gene metabarcoding approach and traditional isolation protocols to investigate oomycetes in orchards and natural stands of Proteaceae across South Africa, South Africa (eastern and western), Australia, and Europe. The RPS10 primers amplified more samples, including various Pythium species, while the ITS primers detected more Phytophthora phylotypes. Both datasets showed that geographic regions influenced oomycete species richness and community composition, while they did not show any variation between orchards and natural vegetation. RPS10 metabarcoding detected the largest number of species and provided greater statistical confidence than ITS1 when considering oomycete species composition. Metabarcoding also showed that orchards had a higher abundance of P. cinnamomi compared to native stands, although this was not found when isolating through baiting of roots and rhizosphere soil. Direct isolation and metabarcoding are complementary, with metabarcoding serving as an early detection tool. However, it cannot distinguish living viable propagules from residual DNA of dead propagules, limiting its use for diagnostic purposes related to Phytophthora management and control. These results, along with those of other recent studies, show that metabarcoding offers an effective tool to describe the dynamics of soil oomycetes in different ecosystems. [ABSTRACT FROM AUTHOR]

Groundwater dependent vegetation (GDV) is increasingly threatened by the transformation of the natural environment. An understanding of the nature of GDV at the appropriate scale helps environmental managers make suitable decisions. This study assesses the potential for mapping the distribution of GDV within the Heuningnes Catchment using multispectral remotely sensed data (i.e., Landsat 8 (L8) and Sentinel 2 (S2)), the derived vegetation indices (Normalised Difference Vegetation Index (NDVI) and the Soil-Adjusted Vegetation Index (SAVI)) and in-situ data. The GDV distribution maps were produced by integrating vegetation productivity, landcover, and topographic layers as GDV indicators. The findings of the study revealed that the spectral indices had a significant influence on the sensor's GDV classification performance. Specifically, the S2-derived SAVI mapped the GDV areas with the highest overall accuracy (97%), followed by the S2-derived NDVI, with an accuracy of 95%. Comparatively, the L8(NDVI) GDV map was achieved with an overall accuracy of 92% and the L8(SAVI) map had an overall accuracy of 96%. The estimated coverage of potential GDV within the catchment ranges between 2.34 and 2.60%. This work demonstrated the capabilities of a combined remote sensing and GIS methodological framework, which can improve our knowledge on GDV. [ABSTRACT FROM AUTHOR]

Questions: Roots are responsible for essential plant functions including water uptake. However, the extent to which root traits (size and structure) determine plant presence in water‐limited environments is still poorly understood. Here we investigated how root traits vary across water availability gradients within a dry South African biome. Location: South Africa. Methods: We measured six below‐ground (root) and eight above‐ground (leaf + stem) traits of 124 individuals of nine dominant woody shrub species from wetter and drier sites (600–700 vs 250–300 mm annual precipitation) in the Fynbos biome of the Cape Floristic Region. Within sites, we sampled from recently burnt and unburnt/more mature vegetation and at three locations along topographical gradients. Results: Drier regions showed greater maximum rooting depth, length, root dry matter content and root to shoot ratio. These trait patterns were consistent at an intraspecific level, along locally drier topographical locations and in post‐fire environments. Roots accounted for significant whole‐plant trait variation. Additionally, in drier conditions, we found increased root allocation deviating from expected global allometric relationships. Our study also demonstrates that the combination of fire and drought in the driest locations results in poor above‐ground vegetation recovery in terms of plant size, cover and individual counts with only resprouters persisting. Conclusions: Our research suggests that root investment in Fynbos shrubs will likely be key for coping with a drier and warmer future and should be a focus of more research for dryland biomes. [ABSTRACT FROM AUTHOR]

Fynbos and afrotemperate forest exist as alternate stable states in the Cape Floristic Region of South Africa. In parts of Table Mountain National Park, afrotemperate forest has expanded in recent decades. The aim of this project was to explore the drivers of this change and distinguish whether this expansion represents a recovery of forest after previous clearance during the 18th century or is a novel expansion of forest range that resulted from policies of fire suppression in the 20th century. To determine the relationships between forest and fynbos and its key drivers, pollen, non-pollen palynomorphs, charcoal, stable isotope ratios (δ13C) and major and trace elements were analysed from late-Holocene sediments extracted from Orange Kloof. Pollen data show that forest cover has fluctuated over the past 3690 years. At the start of the record, under drier conditions from 1670 BCE to ~170 CE, forests contracted, and dry, asteraceous fynbos dominated the landscape. Around ~170 CE there was a shift to ericaceous fynbos as water availability increased. Weak signals of Khoekhoen pastoralists may be visible in the record around 50 CE, indicated by increased spores and charcoal. A regime shift towards increased dominance of the forest occurred ~250 CE, associated with wetter climate. Clear anthropogenic signals are associated with European settlement from 1650 CE. Reinforced by human clearance of forest, fynbos expanded during the cool conditions of the late phase of Little Ice Age (~1750–1850 CE). Forest expansion in the 20th century likely reflects fire suppression and recovery from past forest clearance. Fire needs to be managed accordingly if further expansion of forest into fynbos is to be curbed. [ABSTRACT FROM AUTHOR]

Fire is an important cause of disturbance which directly shapes many ecosystems worldwide. While the effect of fire on the distribution and regeneration of plant species has been widely documented, little is known on how phytophagous insects are reacting to these disturbances.This study explores the survival strategies of various weevil species, a highly diverse phytophagous beetle group in fire‐prone ecosystems of the biodiversity hotspot of the Cape Floristic Region in South Africa. More specifically, we investigated how the lifestyle of species (location of larval development, phenology of adults, and flight ability) correlates with heat tolerance. We hypothesized that wingless species in particular will show better tolerance to heat as they have a limited ability to escape fire rapidly and usually remain hidden in the soil.The thermal tolerance of a set of sixteen species with divergent lifestyles and geographic distribution was measured using a standard heat knockdown protocol at 48°C. Respirometry was then performed on the most resistant species using a ramping protocol in order to determine CTmax.Our results show that the species tested exhibit high variation in thermal tolerance across taxonomic groups, clustering into three modalities: weak, intermediate, and high tolerance to heat stress. In addition, life history traits (diurnal vs. nocturnal adult activity and location of juvenile stages in plant tissues) likely better explain thermal tolerance at the species level than flight ability or the fire‐proneness of ecosystems. Finally, results revealed that some non‐flying weevil species are highly heat tolerant with CTmax values reaching up to 50.2 and 51.9°C in species among the Ocladiinae and Brachycerinae subfamilies, respectively.Climate change is leading to an increase in the impact and frequency of fires. In this context, this study highlights the diversity of strategies developed by arthropods to escape extreme heat in fire prone ecosystems. Further work is necessary to examine the generality of these patterns across other fire prone ecosystems to better understand behavioural compensation and evolutionary responses, especially given the forecast increases in fire driven by drying and warming associated with climate change. [ABSTRACT FROM AUTHOR]

In this study, we studied the diversity of Penicillium occurring in soil collected along the Woodville Big Tree Forest Trail situated close to the coastal town of Wilderness in South Africa. Strains were accessioned into a collection and then identified to species based on β-tubulin DNA sequences, which is the recommended DNA barcode for the genus. The 74 strains were found to represent 18 species, including six we consider undescribed. Here, we introduce them as Penicillium claroviride, P. kalander, P. mattheeae, P. outeniquaense, P. subfuscum, and P. umkhoba. Phylogenetic comparisons were made, and genealogical concordance was demonstrated for these new species using DNA sequences from nuc rDNA internal transcribed spacer region ITS1-5.8S-ITS2 (ITS barcode), β-tubulin, calmodulin, and RNA polymerase II second largest subunit. Notes on morphological characters distinguishing the new species from their close relatives are provided. [ABSTRACT FROM AUTHOR]

Protected areas (PA) in biodiversity hotspots face the challenge of monitoring large numbers of locally rare and threatened plant species at times with limited budgets. Prioritising species according to their local extinction risk could help PA managers to decide which species to monitor. However, there is often very little information available on the species occurrence and extinction risk in the PA. Because of this, PA managers often rely on the national or global Red List for prioritising species at the PA level. Here, we evaluate the effectiveness of using the Red List for species prioritisation and examine the robustness of extinction probability equations for 74 fynbos species in Table Mountain National Park (TMNP). We conducted in-field surveys to verify the persistence of subpopulations previously recorded, following a detection protocol adapted for rare and cryptic plant species. We found that most targeted species were extant within TMNP but with a substantially reduced number of subpopulations. Twenty-six species only had one or two subpopulations remaining. Critically Endangered (CR) species lost on average 4 subpopulations more than Least Concern (LC) species. However, species persistence in TMNP was largely independent of their Red List status. Half of the species represented by just one or two subpopulations were listed as LC. This work shows that prioritising monitoring according to the Red List status is not appropriate at the scale of the individual PA. We suggest that more in-field data and monitoring is required to prevent extinctions occurring in PAs. [ABSTRACT FROM AUTHOR]

The presence of ultraviolet (UV, wavelengths between 300-400 nm) reflectance in insect-pollinated flowers has been linked to pollination efficiency and pollination shifts, but little is known about its prevalence and function in other pollination systems and African species. We chose the genus Erica for studying the prevalence of UV because of its extreme radiation (c. 680 species) in the Cape, South Africa, with a diversity of pollination syndromes. This study quantified the prevalence and brightness of UV reflectance for five Erica pollination syndromes and tested pollinator preferences for UV reflectance in the two groups with the highest prevalence: sunbirds and long-proboscid flies. Our results show that UV colouration is absent or rare in Erica species pollinated by unclassified insects, rodents or wind. About 17 % of bird-pollinated species reflected UV but choice experiments revealed that free-ranging sunbirds showed no preference for UV signals. All sampled long-proboscid fly-pollinated species reflected UV and its experimental removal decreased seed set drastically, suggesting that long-proboscid flies in the Cape strongly prefer or depend on UV and thereby contributed to selecting for the evolution of this signal.

• Erica glabella, Hippia frutescens and Salvia africana-lutea (methanol), and Eriocephalus racemosa (hexane) extracts IC 50 at < 30 µg/mL • Eriocephalus racemosa induced 21.48±2.86% apoptosis similar to cisplatin 23.72±4.36%. • Metabolite profiling of Salvia africana-lutea extract revealed the presence of phosphatidylcholines, triterpenoids, oxepane and 7-O-methylated flavonoids derivatives. Breast cancer is a leading cause of cancer-related deaths in women globally. Even though a plethora of treatments are available, most patients experience adverse effects which affect their quality of life. The aim of this study was to investigate the utility of nine Fynbos plants (Erica magnisylvae E.G.H Oliv., Erica canescens J.C. Wendl. , Erica coccinea L. , Erica glabella Thunb. , Erica corifolia L. , Eriocephalus racemosa L. , Hippia frutescens L., Salvia africana-lutea L. and an unknown Fynbos plant) in treating breast cancer. Solvent extraction of fynbos plants was performed, and crude extracts were evaluated against MDA-MB 231 cancer cell line to determine the cytotoxic activity with the mode of cell death confirmed using flow cytometry. Antioxidant activity and mass spectrometry-based metabolite profiling were performed to characterize and identify the phytochemical constituents of the extracts. The methanol extracts from E. glabella., H. frutescens and S. africana-lutea and the hexane extract from E. racemosa showed promising cytotoxic activities in the screening phase and thus were further evaluated to determine their 50% inhibitory concentrations (IC 50) which were found to be < 30 µg/mL. Flow cytometry analysis of treated MDA-MB 231 cells revealed promising results for the hexane crude extract (leaves) of E. racemosa and stem methanol crude extract of H. frutescens which induced apoptosis in MDA-MB-231 cancer cell line, similar to the reference drug cisplatin. Metabolite profiling of S. africana-lutea extract, the most potent apoptosis inducer in this study, revealed the presence of phosphatidylcholines, triterpenoids, oxepane and 7-O-methylated flavonoids derivatives. It was concluded that E. racemosa and S. africana-lutea are excellent candidates for further development of therapeutic agents in the fight against cancer, given the pressing need for novel efficacious agents. [ABSTRACT FROM AUTHOR]

Background: The subtropical dune thicket (hereafter "dune thicket") of the Cape Floristic Region experiences a wide range of fire exposure throughout the landscape, unlike other dry rainforest formations that rarely experience fire. We sought to determine how fire exposure influences species composition and the architectural composition of dune thicket. Methods: We used multivariate analysis and diversity indices based on cover abundance of species to describe the species composition, architectural guild composition and structure of dune thicket sites subject to different levels of fire exposure, namely low (fire return interval of >100 years), moderate (fire return interval of 50-100 years), and high (fire return interval of 10-50 years). Results: The diversity, cover abundance and architectural guild cover abundance of dune thicket canopy species were strongly influenced by the level of fire exposure such that each level was associated with a well-circumscribed vegetation unit. Dune thickets subject to low fire exposure comprises a floristically distinct, low forest characterized by shrubs with one-to-few upright stems (ca. 4-8 m tall) and a relatively small canopy spread (vertical growers). Of the 25 species in this unit, 40% were restricted to it. Dune thickets subject to moderate fire exposure had the highest abundance of lateral spreaders, which are multi-stemmed (ca. 3-6 m tall) species with a large canopy spread and lower stature than vertical growers. None of the 17 species found in this unit was restricted to it. Dune thickets subject to high fire exposure had the highest abundance of hedge-forming shrubs, these being low shrubs (ca. 0.6-1.4 m tall), with numerous shoots arising from an extensive system of below-ground stems. Of the 20 species in this unit, 40% were restricted to it. Multivariate analysis identified three floristic units corresponding to the three fire exposure regimes. Compositional structure, in terms of species and architectural guilds, was most distinctive for dune thickets subject to high and low fire exposure, while the dune thicket subject to moderate fire exposure showed greatest compositional overlap with the other units. Conclusion: Fire exposure profoundly influenced the composition and structure of dune thicket canopy species in the Cape Floristic Region. In the prolonged absence of fire, the thicket is invaded by vertical-growing species that overtop and outcompete the multi-stemmed, laterally-spreading shrubs that dominate this community. Regular exposure to fire selects for traits that enable thicket species to rapidly compete for canopy cover post-fire via the prolific production of resprouts from basal buds below- and above-ground. The trade-off is that plant height is constrained, as proportionately more resources are allocated to below-ground biomass. [ABSTRACT FROM AUTHOR]

Riparian zones can be characterised botanically into two main areas, a wet bank and a dry bank. These areas have been linked to the duration of inundation by river flow, the boundary between the two being the 1:2 year floodline. Therefore the wet bank is inundated regularly by small floods and the dry bank by larger, less frequent floods, and each may support one to a few distinct plant communities laterally up the bank. Understanding these plant distributions helps rehabilitation projects and Environmental Flow (EFlows) studies as it can inform re-vegetation strategies in the former and help understanding of the links between plants and the river's flow regime in the latter. Systematic sampling and data analysis methods were developed for single channel rivers with relatively undisturbed natural vegetation to identify and locate the different plant communities in the riparian zone. Generic rules using distance and height from the water's edge, rather than the presence or absence of plant species, were calculated to locate the communities. While these statistics were derived from the riparian vegetation along perennial Western Cape rivers, South Africa, the methods could be applied to other perennial single channel river anywhere. [ABSTRACT FROM AUTHOR]

Background The subtropical dune thicket (hereafter “dune thicket”) of the Cape Floristic Region experiences a wide range of fire exposure throughout the landscape, unlike other dry rainforest formations that rarely experience fire. We sought to determine how fire exposure influences species composition and the architectural composition of dune thicket. Methods We used multivariate analysis and diversity indices based on cover abundance of species to describe the species composition, architectural guild composition and structure of dune thicket sites subject to different levels of fire exposure, namely low (fire return interval of >100 years), moderate (fire return interval of 50–100 years), and high (fire return interval of 10–50 years). Results The diversity, cover abundance and architectural guild cover abundance of dune thicket canopy species were strongly influenced by the level of fire exposure such that each level was associated with a well-circumscribed vegetation unit. Dune thickets subject to low fire exposure comprises a floristically distinct, low forest characterized by shrubs with one-to-few upright stems (ca. 4–8 m tall) and a relatively small canopy spread (vertical growers). Of the 25 species in this unit, 40% were restricted to it. Dune thickets subject to moderate fire exposure had the highest abundance of lateral spreaders, which are multi-stemmed (ca. 3–6 m tall) species with a large canopy spread and lower stature than vertical growers. None of the 17 species found in this unit was restricted to it. Dune thickets subject to high fire exposure had the highest abundance of hedge-forming shrubs, these being low shrubs (ca. 0.6–1.4 m tall), with numerous shoots arising from an extensive system of below-ground stems. Of the 20 species in this unit, 40% were restricted to it. Multivariate analysis identified three floristic units corresponding to the three fire exposure regimes. Compositional structure, in terms of species and architectural guilds, was most distinctive for dune thickets subject to high and low fire exposure, while the dune thicket subject to moderate fire exposure showed greatest compositional overlap with the other units. Conclusion Fire exposure profoundly influenced the composition and structure of dune thicket canopy species in the Cape Floristic Region. In the prolonged absence of fire, the thicket is invaded by vertical-growing species that overtop and outcompete the multi-stemmed, laterally-spreading shrubs that dominate this community. Regular exposure to fire selects for traits that enable thicket species to rapidly compete for canopy cover post-fire via the prolific production of resprouts from basal buds below- and above-ground. The trade-off is that plant height is constrained, as proportionately more resources are allocated to below-ground biomass.

Wildfire affecting urban areas at the wildland urban interface (WUI) is a growing global concern, where management is important for urban residents as well as wildland vegetation. We used a socio‐ecological system perspective to investigate the interactions of urban land with a fire‐dependent wildland in South Africa's City of Cape Town (CoCT). We examined changes in population growth, land cover change and related WUI footprint, occurrence of large fires, and related policies over time. We used Landsat data to track changes over the period 1990–2019 in the formal and informal urban and wildland footprint, census data to track changes in population, and difference normalised burn ratio and MODIS burned area product to track large fires. The urban footprint has expanded greatly and through consolidation has led to the reduction of the WUI. Furthermore, evidence points to an increase in fire suppression, even though national policies ask for wildfires to run their course where possible and appropriate. As a result of pressure from urban residents, local managers prefer short term fire suppression to long term risk reduction for urban areas and ecological management of wildland. Framing the problem as a socio‐ecological system enabled us to highlight how WUI management is a product of interaction between urban development, wildland type and policies. Our findings emphasise the point that wildland management is driven by urban residents and local municipalities, with national fire and disaster management policies not fully implemented. [ABSTRACT FROM AUTHOR]

• The alien Melaleuca rugulosa (Myrtaceae) has spread over 1.2 hectares in South Africa.. • The one invasive population is in pristine fynbos in Table Mountain National Park. • Recent fires most likely triggered the invasion of this serotinous species. • Melaleuca rugulosa can still be extirpated and should be listed as 1a under NEM:BA. Several Melaleuca (Myrtaceae) species are invasive globally. Recently an increase in invasive species from this genus have been reported in South Africa. Here we document the first detailed assessment of the distribution and invasive potential of Melaleuca rugulosa in South Africa. We assess population structure, determine the current and potential future distribution in South Africa using climatic variables, conduct a risk analysis, provide recommendations for management, and consider the feasibility of eradication. We found one naturalising population of ∼665 individuals covering more than 1.2 hectares. It was first recorded in 1961 invading the native fynbos vegetation in the Table Mountain National Park (TMNP). Two recent fires – in 2009 and 2016 – likely enhanced spread, this spread happened despite undocumented clearing attempts in the last decade. The south-western Cape is the most climatically suitable for M. rugulosa, with most other wetter areas of the country being only partly suitable regions. The risk analysis indicated a medium risk, and we suggest listing M. rugulosa as category 1a (eradication target) under the South African National Environmental Management: Biodiversity Act (10/ 2004). Given the small area occupied, ease of access and the lack of a soil seed bank, the population can be extirpated from Devil's Peak within the TMNP. We highlight that serotinous alien species, particular from the Myrtaceae, should receive more attention as potential invasive species in fire-driven ecosystems and that their lack of invasiveness in areas where fire is suppressed, should not be misinterpreted as being a low-risk species. [ABSTRACT FROM AUTHOR]

• The suitability of road verges as habitats for fynbos plants is poorly understood. • We investigate pollination of ornithophilous Erica glandulosa in road verges. • Fewer flowers were visited by birds closer to the road. • Fewer flowers were visited in road verges next to transformed land. • On average, 20–30% of flowers found within 10 m of the road were visited by birds. Road verges can provide important habitats for plants, especially in transformed landscapes. However, roads and their associated traffic have several adverse impacts on ecosystems that can disrupt vital ecological processes, including pollination. In transformed landscapes, the negative effects of roads on pollination might be complemented by impacts of large-scale habitat modification. In these landscapes, road verge populations of plants that rely on pollinators could thus be at risk of pollination failure. This study investigates the pollination of a reseeding, bird-pollinated shrub, Erica glandulosa , in road verges of a fragmented and transformed rural landscape in the southeastern Cape Floristic Region. We test for road impacts on pollination by comparing number of ruptured anther rings – a proxy for pollination – in fynbos vegetation fragments at different distances from the road (0–10, 20–30 and 40–50 m). We also test whether different land-cover types (intact fynbos, alien thickets and rangelands/pastures) next to road verges influence the number of ruptured anther rings. After controlling for robbing rate and plant density, fewer flowers were pollinated near the road (0–10 m) than farther away (beyond 20 m), and fewer flowers were pollinated where road verges occurred next to alien thickets or pastures/rangelands compared to intact fynbos. However, bird pollinators were not excluded in road verges: on average, ca. 20–30% of flowers occurring within 10 m of the road were still visited by birds. While we expect the reduced pollination rate to have a negative effect on the fecundity of road-verge plants, it remains to be tested whether the pollination rate observed in verges is sufficient to sustain populations of bird-pollinated, seed-dependent plants. [ABSTRACT FROM AUTHOR]

• Secondary invader species after alien tree clearing are seldom reported. • Secondary invader richness is lower in riparian Fynbos than non-riparian areas. • Secondary invaders are a mix of annuals and perennials (shrubs, herbs and graminoids). • Secondary invader richness persisted up to a decade after clearing. After the clearing of invasive alien plants, non-target alien species often move in. This is known as secondary invasion and these alien species can suppress native plant species' recovery. This is a global problem that has only recently received attention in South Africa. But whether secondary invaders in riparian areas have similar effects than those in more terrestrial areas is largely unknown globally and in South Africa. Therefore, here we ask which species and growth forms are associated with secondary invasion in riparian areas in the Fynbos biome, and secondly whether secondary invader species richness changes over time post clearing. We found 13 secondary invader species in a riparian area after clearing of alien invasive Eucalyptus trees. In the first year after clearing, there were only annuals, but thereafter it was a mix of annuals and perennials (shrubs, herbs, and graminoids). Secondary invader richness did not significantly differ with time after clearing, persisting even up to 10 years. In this riparian area, secondary invader species richness was much lower than that for non-riparian Fynbos areas. From this preliminary study we highlight the need for more research in understanding how secondary invaders influence restoration efforts and native species recovery in riparian systems. [ABSTRACT FROM AUTHOR]

Many plant species have floral morphologies that restrict access to floral resources, such as pollen or nectar, and only a subset of floral visitors can perform the handling behaviors required to extract restricted resources. Due to the time and energy required to extract resources from morphologically complex flowers, these plant species potentially compete for pollinators with co‐flowering plants that have more easily accessible resources. A widespread floral mechanism restricting access to pollen is the presence of tubular anthers that open through small pores or slits (poricidal anthers). Some bees have evolved the capacity to remove pollen from poricidal anthers using vibrations, giving rise to the phenomenon of buzz‐pollination. These bee vibrations that are produced for pollen extraction are presumably energetically costly, and to date, few studies have investigated whether buzz‐pollinated flowers may be at a disadvantage when competing for pollinators' attention with plant species that present unrestricted pollen resources. Here, we studied Cyanella hyacinthoides (Tecophilaeaceae), a geophyte with poricidal anthers in the hyperdiverse Cape Floristic Region of South Africa, to assess how the composition and relative abundance of flowers with easily accessible pollen affect bee visitation to a buzz‐pollinated plant. We found that the number of pollinator species of C. hyacinthoides was not influenced by community composition. However, visitation rates to C. hyacinthoides were reduced when the relative abundances of flowers with more accessible resources were high. Visitation rates were strongly associated with petal color, showing that flower color is important in mediating these interactions. We conclude that buzz‐pollinated plants might be at a competitive disadvantage when many easily accessible pollen sources are available, particularly when competitor species share its floral signals. [ABSTRACT FROM AUTHOR]

Aim: To understand effects of fire history and landscape composition on butterfly diversity in a fragmented agricultural landscape. Location: We studied critically endangered renosterveld remnants within the fynbos biome in the Swartland municipality, Western Cape, South Africa, a global biodiversity hotspot. Method: We selected survey sites on renosterveld fragments in the agricultural landscape along a gradient of fire history to test the response of biodiversity patterns to fire and landscape composition. We surveyed butterfly species richness, abundance and community composition as well as vegetation structure in five survey rounds on 58 sites between August 2018 and April 2019. We analysed data through linear modelling and multidimensional scaling. Results: Fire was associated with reduced shrub and understorey plant cover and with increased plant species richness. Butterfly species richness was three to four times higher when natural habitat increased in the surrounding landscape (within a 2 km radius), while butterfly abundance was negatively associated with increasing time since fire, with approximately 50% fewer individuals after 9 years. Fire was indirectly associated with increased butterfly species richness and abundance through the alteration of vegetation structure, particularly through removal of shrubs and enhanced plant diversity. Low‐mobility butterfly species were more positively associated with less vegetation cover than were high‐mobility species, which were more associated with sites characterized by long absence of fire. Main conclusions: Our findings suggest that species respond differently to fire, so a diversity of fire frequencies is recommended. Partially burning areas approximately every 10 years may benefit particularly low‐mobility butterfly species through gap creation and fostering plant diversity. Hence, including fire into management activities can benefit butterfly and plant populations alike in critically endangered renosterveld. [ABSTRACT FROM AUTHOR]

The Agulhas Long-billed Lark Certhilauda brevirostris is a South African endemic and is restricted to the fynbos habitat of the Agulhas Plain in the southwestern corner of South Africa. The 1990, 2014, and 2018 land use land cover (LULC) databases prepared for South Africa were used to determine the LULC categories that best describe suitable habitat for this bird using beta regressions. Previously published densities of Agulhas Long-billed Lark and the surface area of the LULC categories considered suitable habitat for the birds were used to estimate their historical and current population sizes, and the rates of change in the bird's population. Beta regression models were compiled from the bird's adjusted reporting rate and the total surface area, and three other landscape metrics, of the per pentad LULC categories considered suitable habitat for them. These models revealed that although the Agulhas Long-billed Lark is adversely affected by the loss of its natural fynbos habitat these adverse effects have been offset by an increase in the availability of fallow fields in summer. This confirms previous observations that agriculture may have allowed the Agulhas Long-billed Lark to increase in numbers. The Agulhas Long-billed Lark's extent of occurrence (EOO) was estimated at 1 322 509 ha (n = 197 pentads) with an area of occupancy (AOO) estimated to be 1 076 854 ha in 2020. The decline in habitat available to the birds was estimated to be 3.5% over three generations (10.5 years). The present study provides improved estimates of the population of the Agulhas Long-billed Lark of between 146 344 and 264 691 individuals, with between 60 753 and 109 883 individuals in natural habitat, and between 85 591 and 154 808 individuals in transformed habitat. The results of the present study indicate that the Agulhas Long-billed Lark's Near Threatened status should be reviewed. [ABSTRACT FROM AUTHOR]

As Proteaceae subfamily Proteoideae are richly represented in the Cape Floristic Region of southern Africa and in south-western Australia, it is a convenient group for comparative studies of evolution and adaptation of plants in widely separated areas with a Mediterranean-type climate. Although species of Proteoideae attract considerable attention of researchers, the structural diversity of wood in this group remains under-explored. The wood structure of 51 species of 14 African and Australian genera of Proteoideae (Proteaceae) has been studied. These taxa are uniform in their wood structure; the diversity patterns are more related to plant stature, climatic factors and fire-survival strategies than to the taxonomy or phylogeny of the subfamily. Increases in length and diameter of fibres and diameter of pits in fibre walls are associated with a shift from a semi-arid winter-dry climate to a milder climate with winter rainfall. These trends may imply the transition from non-conducting imperforate tracheary elements to conducting elements in Mediterranean-type climatic regions. This presumable gain of hydraulic function of imperforate tracheary elements could be explained by adaptation to freeze–thaw stress during the late Quaternary, at least in the Cape Region. Vessel grouping shows no correlations with climatic factors. The seeders have a higher vessel frequency and narrower and lower rays than sprouters. We hypothesize that the larger rays in overground stems of sprouters serve as the sites of epicormic buds that provide for resprouting after fire or other damage. The occurrence of sclerified cells and/or irregularly arranged (occasionally circular) tracheary elements in broad rays of some species are thought to be responses to excessive sucrose transport in secondary phloem. [ABSTRACT FROM AUTHOR]

• Secondary invader germination is not influenced by available soil nitrogen. • Elevated available soil nitrogen favours secondary invader growth. • Secondary invader species respond differently to available soil nitrogen. • Secondary invasion can be managed through a reduction in soil nitrogen levels. Invasive alien nitrogen-fixing species, such as Australian acacias, often leave a legacy of elevated available soil nitrogen after their removal. This legacy effect can facilitate secondary invasion by other alien species, thereby preventing natural restoration of areas being managed. To restore viable native plant communities in ecosystems where secondary invasion is a barrier to restoration, it is important to understand the soil legacy effects of invasions. Using Acacia saligna (Labill.) H. L. Wendl. (Fabaceae) invasions in the South African fynbos as case study, we determined (1) the extent to which levels of available soil nitrogen influence the germination and growth of secondary invaders; and (2) how this differs between secondary invader species. We chose five of the most common species that have been identified as secondary invaders after clearing invasive A. saligna in the Cape Flats Sand Fynbos: (i) Avena fatua (L.) (Poaceae), (ii) Briza maxima (L.) (Poaceae), (iii) Bromus diandrus (Roth.) (Poaceae), (iv) Hypochaeris radicata (L.) (Asteraceae), and (v) Raphanus raphanistrum (L.) (Brassicaceae). Using proportional fertigation, we created soil nitrate levels similar to those found in non-invaded areas (1mg/kg), and the lowest (3 mg/kg), median (7.5 mg/kg) and highest (12 mg/kg) levels typically found in areas previously invaded by A. saligna up to ten years after clearing. For each soil nitrate level, we germinated secondary invader seeds (five seeds per petri dish) in an incubator (five species × four soil nitrate levels × five replicates = 100 petri dishes). Furthermore, for each soil nitrate level, we grew secondary invaders (one plant per pot) in a greenhouse tunnel for five months (five species × four soil nitrate levels × five replicates = 100 pots). There was no significant relationship between germination success and soil nitrate level for any species. However, root and shoot dry mass were significantly positively correlated to soil nitrate level for all species. The relationship was nonetheless only linear for Bromus diandrus, Hypochaeris radicata , and Raphanus raphanistrum. These results indicate that the legacy of elevated available soil nitrogen does not have an effect on the germination of secondary invaders, but favours their growth. Therefore, secondary invasion can be managed through a reduction in soil nitrogen levels. However, secondary invader growth does not decrease at the same rate for all species in response to a decrease in available soil nitrogen. Thus, the use of soil nitrogen reduction as a tool for the management of secondary invasions should take into account the species being managed. However, given that multiple secondary invader species often dominate a restoration site, restoration efforts should reduce soil nitrogen to non-invaded levels to account for the different response rates to available soil nitrogen, and simply management efforts. [ABSTRACT FROM AUTHOR]

Context: It has been proposed that the distribution of resprouter and seeder Erica in the Cape Floristic Region (CFR) of South Africa is determined by drought rather than by fire frequency. Seedlings of Erica seeders are predicted to withstand the mild droughts of the southwest CFR better than those of Erica resprouters, which would account for the abundance of seeders in this region. Aims: This study aimed to test this hypothesis using Erica coccinea (L.), which contains both a resprouter and a seeder form. Methods: One-year-old seedlings of both forms were subjected to a progressively severe 50-day drought in the greenhouse. Key results: Contrary to expectations, seeder seedlings had 67% higher mortality than resprouters during the initial phase of drought (30% vs 18% after 32 days). However, both forms were unable to survive as the drought progressed, resulting in 95% mortality by Day 50. There were limited differences between the forms in gas exchange and water potential, and no difference in root:shoot ratios. However, resprouters had significantly higher soluble carbohydrates than did seeders, which may have aided in delaying mortality. Conclusions: Our results showed no evidence of resprouter seedlings being more vulnerable to mild drought than seeders in E. coccinea. Implications: Our findings challenge the hypothesis that the distribution of this species can be explained by the vulnerability of resprouter seedlings to mild drought. We tested drought sensitivity in reseeder and resprouter seedlings of E. coccinea , a species that contains both reseeder and resprouter morphs. Contrary to expectations, seeder seedlings were more drought sensitive than were resprouter seedlings. Our results challenge the drought-distribution hypothesis for Erica in the Cape Floristic region. [ABSTRACT FROM AUTHOR]

Entomopathogenic nematodes (EPNs) are microscopic roundworms that are found in soil worldwide. They deliver an important ecosystem service through preventing natural flares in insect reproduction by means of utilising the soil stages of insects as a food source and by acting as natural biocontrol agents. A survey of EPNs was conducted in the JS Marais Nature Reserve, Stellenbosch, in the Western Cape province of South Africa. Soil samples were baited with the larvae of three susceptible hosts, codling moth (Cydia pomonella), wax moth (Galleria mellonella) and mealworm (Tenebrio molitor) to determine the presence of EPN. Of the 76 soil samples collected across the reserve, 39 were found to be positive for the presence of EPN (51.32%). Among the positive samples, 87% contained Steinernema isolates, 8% contained Heterorhabditis and 5% contained the Oscheius sp. Morphological and molecular studies were performed to characterise the isolates to species level. The Steinernema species were identified as Steinernema khoisanae in 34 samples, and as Steinernema nguyeni in five samples. The only species of Heterorhabditis found was H. safricana, which was identified from three samples. An unknown Oscheius sp. was found in two samples. The reserve’s population of S. khoisanae showed interesting inter-individual variation (93%) early in the internal transcribe spacer (ITS) region, leading to short single-usable sequences, which, in most cases, included only the ITS1 or ITS2 region. However, using the D2D3 confirmed their identity as S. khoisanae, with such occurring in all areas and soil types of the reserve. Conservation implications: The undisturbed alluvial fynbos and renosterveld of the JS Marais Nature Reserve showed high EPN abundance and diversity in stark contrast to the agro-ecosystems present in the Cape floristic region. This finding, on a micro level, should be conserved for future bioprospecting in the fynbos for EPNs with potential as biocontrol agents.

Habitat loss and habitat fragmentation are amongst the major drivers of biodiversity loss globally. Although habitat fragmentation poses additional threats to biodiversity beyond habitat loss alone, the IUCN's Red List of Ecosystems (RLE) does not provide guidance on how to assess these threats. This study develops an approach for incorporating habitat fragmentation into the RLE threat assessment and investigates additional insights such an analysis could provide beyond the analysis of distribution trends. This is achieved by quantifying RLE criteria A and B (distribution reduction, restricted distribution and decline) and comparing outcomes with indices of habitat fragmentation (core area, Largest Patch Index, Patch Cohesion Index and Aggregation Index) in the Cape Floristic Region of South Africa. Results revealed that much of the Cape Floristic Region is severely threatened by both landscape transformation and habitat fragmentation, but that treating the habitat fragmentation indices as additional RLE criteria did not alter the ecosystem threat assessment outcomes. Whilst this suggests that the existing RLE criteria implicitly account for habitat fragmentation, the relationship between fragmentation indices and RLE criteria were weak and highly variable in some cases, indicating that the RLE criteria alone do not sufficiently account for the threat of habitat fragmentation. Supplementing the RLE with habitat fragmentation measures highlights additional, unique information on threats to ecosystems. This simple approach has the potential to assist in setting conservation priorities and management goals, particularly in fragmented ecosystems. [ABSTRACT FROM AUTHOR]

1. Fire is commonly identified as strong driver of alternative stable states such as adjacent open-versus closed-canopy vegetation types. The absence of open-canopy species from closed-canopy understoreys, where light availability is low and dynamic, however, suggests shade tolerance is an integral determinant of such vegetation boundaries. While the importance of light dynamics between alternative stable states has been acknowledged, the physiological mechanisms behind sun versus shade tolerance are unclear. Here we investigated the differences in light interception and carbon assimilation of open- and closed-canopy species, and whether this contributes to the maintenance of alternative stable states. 2. Evergreen forest and fynbos species were grown under three light availability treatments (24%, 54% and 100%) in a glasshouse with their photosynthetic response to continuous and fluctuating light, dark respiration, root respiration, biomass and leaf traits quantified. 3. Fynbos species displayed smaller, thicker and tightly aggregated leaves compared to forest species. Under low light, fynbos species experienced some mortality, and showed lower light-use efficiency with fluctuating light and lower in situ photosynthetic rates under the 54% light treatment compared to forest species (0.8 vs. 3.4 µmol CO2 m-2 s-1). 4. Synthesis. Contrasting light availability in forest and fynbos selects for dissimilar traits, where fynbos species are unable to efficiently intercept light and maintain a positive carbon balance under low, dynamic light compared to forest species. This shade intolerance is exacerbated by divergent nutrient and fire regimes in forest and fynbos environments, requiring incompatible trait specialisations that promote the emergence and maintenance of alternative stable states. [ABSTRACT FROM AUTHOR]

• In the 30–50-year absence of fire, thicket does not replace fynbos on all sites. • Fynbos persists on dune crests where it occupies a drier sites than thicket. • Fynbos shrubs are invading a dense turf, or grazing lawn adjacent to the coast. • Woody plant cover increased everywhere in the study area over the past three to five decades. • A shift in land use from subsistence agriculture to tourism most likely underpins these vegetation changes. It is hypothesized that in the Holocene dune fynbos-thicket mosaics of the Cape, decades-long absence of fire results in closed-canopy thicket replacing more open fynbos shrublands. We tested this hypothesis by analyzing repeat photographs from 16 sites at Cape St Francis in the south-eastern Cape Floristic Region. The period of monitoring ranged from 55 to 17 year and most sites had been last burnt between 30 and 50 years ago. We divided the sites into coastal (salt wind-exposed) and inland zones and computed, for each pair of photographs, the rate of change of four plant types, namely thicket shrubs, fynbos woody, fynbos herbaceous and grass. Coastal zone sites showed a significant increase in thicket shrub cover and a significant decline in both grass and fynbos herbaceous cover. Fynbos woody cover declined in the face of thicket invasion, but increased in grassy sites, most likely due to a decline in herbivory intensity. No significant changes in plant types were observed in the inland sites, although thicket shrub cover did increase marginally at the expense of fynbos woody plants. However, thicket invasion was restricted to swales and lower dune slopes; the dune fynbos of the upper slopes and crests remains uninvaded by thicket and surprisingly vigorous after 30–50 year without fire. This is consistent with the notion that fynbos species occupy drier sites than thicket in these dune landscapes and regular fire is not a prerequisite for its persistence. Overall, we showed a large increase in woody plant cover throughout the study area. While this pattern is consistent with predictions for vegetation change in response to atmospheric [CO2] pollution, it can also be explained by land use changes experienced in the study area, starting in the early 1960s, involving a shift from subsistence agriculture to holiday resort development and tourism. [ABSTRACT FROM AUTHOR]

The diverse bacterial communities in and around plants provide important benefits, such as protection against pathogens and cycling of essential minerals through decomposition of moribund plant biomass. Biodiverse fynbos landscapes generally have limited deadwood habitats due to the absence of large trees and frequent fire. In this study, we determined the effect of a fire disturbance on the bacterial communities in a fynbos landscape dominated by the shrub Protea repens using 16S ribosomal RNA amplicon sequencing. The bacterial community composition in newly formed fruiting structures (infructescences) and soil at a recently burnt site was different from that in an unburnt site. Bacteria inhabiting P. repens infructescences were similar to well-known taxa from decomposing wood and litter. This suggests a putative role for these aboveground plant structures as reservoirs for postfire decomposer bacteria. The results imply that inordinately frequent fires, which are commonplace in the Anthropocene, are a significant disturbance to bacterial communities and could affect the diversity of potentially important microbes from these landscapes. [ABSTRACT FROM AUTHOR]