Southern African Species Research Articles

A taxonomic revision of Schoenus cuspidatus and allies (Cyperaceae, tribe Schoeneae)—Part 1

The first of a two-part taxonomic revision of the morphologically complex Schoenus cuspidatus and allies group is presented. This revision builds on two recent taxonomic works of which the first transferred 24 southern African species from Tetraria and Epischoenus into Schoenus, and the second revised the taxonomy of the Schoenus compar – Schoenus pictus and allies group, as well as described three new species from South Africa. Here, we use data from recent field collections and a review of specimens from 12 herbaria to revise the delimitations and distributions of three species (Schoenus bolusii, Schoenus exilis and Schoenus graminifolius). In addition, we describe seven new species: six of which are endemic to the Cape Floristic Region (Schoenus calceolus, Schoenus crassiculmis, Schoenus submarginalis, Schoenus prophyllus, Schoenus purpurascens and Schoenus quartziticus), while the seventh is endemic to the Eastern Cape and KwaZulu Natal Provinces of South Africa (Schoenus limosus). We also resolve nomenclatural and species delimitation issues in Schoenus auritus and Schoenus ligulatus, with Schoenus autumnalis and Schoenus variabilis being subsumed in an enlarged circumscription of Schoenus ligulatus. Species in the Schoenus cuspidatus group are caespitose, perennial graminoids, with scapose and terete culms. However, there are differences in sheath and ligule type, which can be either firm or membranaceous, as well as leaf type, which vary from channelled and terete to non-channelled and flat. Importantly, differences in spikelet and nutlet shape distinguish many of the species in this group. A taxonomic key is presented, the nomenclature is updated, and detailed descriptions and distribution maps are provided for these 12 Schoenus species.

Deverra rapaletsa (Apiaceae), a new limestone endemic species from the Ghaap Plateau, Northern Cape, South Africa

We describe a new prostrate species of Deverra (Apiaceae), D. rapaletsa Magee & Zietsman, from the Ghaap Plateau in the Griqualand West Centre of endemism, South Africa. This is the third species of Deverra in southern Africa and brings the total number of species in the genus to 10. The three southern African species are separated from the rest of the species in northern African and Arabia by an arid disjunction. The new species is distinguished by the prostrate habit, densely warty ovaries and slender branches with short internodes. Deverra rapaletsa is known from two populations and favours limestone outcrops.

An inventory and analysis of the food plants of southern Africa

The food plants of southern Africa have not yet been been systematically recorded and the main patterns of plant use have therefore never been studied. The book by Fox and Norwood Young (1982) entitled “Food from the Veld” has been the most comprehensive to date and has become the standard reference work on the subject. However, this publication has become outdated and it is evident that many species were not included. We present here, for the first time, a comprehensive inventory and checklist of the edible plants of southern Africa, i.e., the Flora of Southern Africa (FSA) region. Seventy-four literature sources, including books, journal articles, checklists, grey literature and published ethnobotanical surveys were used to compile the inventory, which includes 1740 species (more than double the number listed by Fox and Norwood Young). All edible plants were marked-off in an Excel spreadsheet of all southern African plant species, made available by the South African National Biodiversity Institute (SANBI). Using the Excel format, it was possible to easily explore the main patterns relating to the frequency of citation of the species, the number of species at different taxonomic ranks (families, genera and species), the plant parts that are used and the use categories within the region. For a selection of 13 indigenous cultural/language groups (for which adequate information was available), we quantified the local preferences (for the most species-rich families, the most commonly used plant parts and the most frequent categories of use. The food plant data for southern Africa were also compared to sub-Saharan Africa and the entire world. Surprisingly, it was found that the Apocynaceae was the most species-rich family of southern Africa food plants, with a total of 137 species, followed by the Fabaceae (135 species), Asteraceae (94 species) and Poaceae (73 species). A similar pattern was found in sub-Saharan Africa, but with Fabaceae in the first position, followed by Apocynaceae. The family-level pattern for the entire world is different, where the Apocynaceae is unimportant, being replaced by Rosaceae (the last-mentioned is of very low significance in Africa). The most species-rich food plant genus in southern Africa is Searsia, while Solanum nigrum and Sclerocarya birrea have the highest frequency of citation in the literature. The most popular plant part used as a food in southern Africa, as well as in the entire world, are fruits, followed by leaves and then underground storage organs. The most species-rich category of food plant use is those consumed raw (and mostly in situ) as snacks, followed by those which are cooked as vegetables. The Apocynaceae have mostly edible underground storage organs as the edible parts, while Fabaceae is more diverse. Fruits and leaves have been determined as the most important plant parts used as food for most of the cultural groups except for the Khoekhoe group, where underground parts are the most important. For all of the cultural groups, plants used for snacks were the most important. A chronological list of publications shows that there were seven major contributions since the first survey by Van der Stel in 1685. The comprehensive inventory provides profound new insights into foraging and human food ecology and may also have value in interpreting and reconstructing the availability of food plants during the evolution of early humans in southern Africa.

Immature Stages of Beetles Representing the ‘Opatrinoid’ Clade (Coleoptera: Tenebrionidae): An Overview of Current Knowledge of the Pupal Morphology

This paper summarizes current morphological data on pupal stages of representatives of the ‘Opatrinoid’ clade (Tenebrionidae: Tenebrioninae). Based on recovered knowledge gaps, directions for future research are provided. Additionally, pupae of three following Southern African species are described and illustrated: Gonopus tibialis (Platynotini: Platynotina), Parastizopus armaticeps (Opatrini: Stizopina) and Zadenos mulsanti (Dendarini: Melambiina).

Antlions of southern Africa: Syngenes Kolbe, 1897, with descriptions of two new species and comments on extra-limital taxa (Neuroptera: Myrmeleontidae: Acanthaclisini).

The southern African species of Syngenes Kolbe, 1897, are revised and compared with their Afrotropical congeners. Three species occur in the region: S. longicornis (Rambur, 1842) and two new species, S. medialis and S. scholtzi, described and illustrated below. A key to the Afrotropical taxa is provided. The larva of S. longicornis is illustrated. The genus is widespread in the Afrotropical Region and extends to the Middle East and Oriental Region. Syngenes species are typically broad-winged antlions, with irregular bifurcate and biaereolate cells between the costa and subcostal veins, which distinguish them from other members of the tribe Acanthaclisini.

Mechanisms of tooth damage and Paranthropus dietary reconstruction

According to the current fossil record, the extinct hominin genus Paranthropus and the genus Homo both first appeared ∼2.7 million years ago. Despite this similarity in geological age, Paranthropus evolved enormous postcanine teeth with very thick enamel while Homo evolved smaller teeth. Results from contact mechanics models derived from multiple scales of tooth damage (microwear, macrowear, and fracture) are reviewed to examine this evolutionary divergence and the role that diet may have played in it. Each scale of investigation reveals different kinds of evidence that can be combined into a more complete picture of hominin diet and feeding behaviour. Microwear reveals information about recent feeding events, while macrowear and fracture record longer-term trends. The synthesis of all three levels of evidence exposes significant dietary diversity, not only between these two hominin genera but within them as well. Within Paranthropus, the eastern and southern African species (P. boisei and P. robustus, respectively) were morphologically similar but appear to have been functionally different. Whereas P. boisei apparently used its teeth to consume large quantities of low quality vegetation, P. robustus had a more varied diet that included harder objects, possibly items such as seeds, nuts, or underground storage organs.

Taxonomic revision of a darkling beetles genus Anaxius (Tenebrionidae: Pedinini: Helopinina).

The genus Anaxius Fåhraeus, 1870 (Tenebrionidae: Helopinina) is revised to include seven Southern African species, four of which are new. A taxonomic treatment of the genus is provided including a morphological study, new species descriptions, keys, illustrations, and notes on species distributions. The following species are treated: Anaxius bloubergensis sp. nov., A. campbellae Koch, 1958, A. limpopoensis sp. nov., A. meletsensis sp. nov., A. obesus Fåhraeus, 1870, A. prozeskyi Koch, 1958, and A. pseudoloensus sp. nov. A lectotype is designated for Anaxius obesus Fåhraeus, 1870 to fix the taxonomic status of this species. Anaxius montiscaerulei Koch, 1958 is considered as a synonym of A. campbellae.

A taxonomic evaluation of the Thesium confine species complex (Santalaceae)

Background: Thesium L. is the largest genus in the family Santalaceae (sandalwood family). The last taxonomic revision of the southern African species dates back to 1925. An urgent revision of the genus is required as indicated in a recent national biosystematics research strategy for South Africa.Objectives: To revise the Thesium confine species complex (Thesium durum, T. confine and Thesium spartioides) and to update the typification, nomenclature, descriptions and distribution ranges.Method: Morphological characters were studied using own field collections as well as herbarium specimens from K, NU, PRE and PRU and images on Global Plants (JSTOR). Distribution ranges of the studied species were updated.Results: An examination of morphological characters revealed great similarity between T. spartioides and T. confine. Both species have an herbaceous habit, decumbent growth form, terminal (or less frequently axillary) inflorescences and a sympatric northern distribution in South Africa. Thesium durum differs from T. spartioides and T. confine in having a shrubby habit, erect growth form and axillary inflorescences and occurs in the southern part of South Africa.Conclusion: Thesium spartioides is synonymised under T. confine, and T. durum is retained as a separate species.

Shedding new light on the origin and spread of the brinjal eggplant (Solanum melongena L.) and its wild relatives.

While brinjal eggplant (Solanum melongena L.) is the second most important solanaceous fruit crop, we lack firm knowledge of its evolutionary relationships. This in turn limits efficient use of crop wild relatives in eggplant improvement. Here, we examine the hypothesis of linear step-wise expansion of the eggplant group from Africa to Asia. We use museum collections to generate nuclear and full-plastome data for all species of the Eggplant clade. We combine a phylogenomic approach with distribution data to infer a biogeographic scenario for the clade. The Eggplant clade has Pleistocene origins in northern Africa. Dispersals to tropical Asia gave rise to Solanum insanum, the wild progenitor of the eggplant, and to African distinct lineages of widespread and southern African species. Results suggest that spread of the species to southern Africa has been recent and likely facilitated by large mammalian herbivores, such as the African elephant and impala feeding on Solanum fruit. Rather than a linear 'Out Of Africa' sequence, our results are more consistent with an initial dispersal event into Asia, and subsequent wide dispersal and differentiation across Africa driven by large mammalian herbivores. Our evolutionary results will affect future work on eggplant domestication and affect the use of wild relatives in breeding of this increasingly important solanaceous crop.

The correct name in Knowltonia for an iconic southern African species earlier known as Anemone tenuifolia and A. capensis (Ranunculaceae)

The correct name in Knowltonia for an iconic southern African species earlier known as Anemone tenuifolia and A. capensis (Ranunculaceae)

On the taxonomic status and distribution of African species of Otomops (Chiroptera: Molossidae).

BackgroundFree-tailed bats of the genus Otomops are poorly known, and most species are documented from a handful of widely scattered localities. Recently, two allopatric species of Otomops were recognized in continental Africa: Otomops martiensseni (Matschie, 1897) in southern, central and western Africa, and the new species O. harrisoni Ralph et al., 2015 in the northeast and in Yemen.MethodsWe collected additional samples of Otomops in Kenya and Rwanda where the ranges of these taxa approach one another to clarify their geographic ranges and taxonomic status. Mitochondrial and nuclear intron sequences served to identify and delimit species; we also documented their echolocation call variation and ectoparasite complements.ResultsOtomops martiensseni, the southern African species, was documented in northern Kenya in Marsabit National Park. O. harrisoni, the northeastern African–Arabian species, was documented in southern Kenya and in a cave in Musanze District, Rwanda. Moreover, individuals of both species were found together at the Musanze cave, establishing them in precise spatial and temporal sympatry. Analyses of mitochondrial and nuclear loci identify no evidence of admixture between these forms, although available samples limit the power of this analysis. Echolocation call differences are also apparent among the three localities we analyzed. Three orders of insects and two families of mites are newly reported as ectoparasites of O. harrisoni.DiscussionOur results corroborate species rank for O. harrisoni and establish a zone of potential geographic overlap with O. martiensseni spanning at least 800 km of latitude. The new records establish the species in sympatry in northern Rwanda and add an additional species to the bat faunas of both Kenya and Rwanda. Future studies are needed to understand Otomops roosting requirements and movements, thereby explaining the paucity of known colonies and yielding better estimates of their conservation status. The discovery of mixed roosting associations in Rwanda invites further investigation.

Artificial and assisted natural regeneration of socio-economically important southern African tree species

Artificial and assisted natural regeneration of socio-economically important southern African tree species

First records of water bears (Phylum Tardigrada) from Swaziland

There are no published records of water bears (Phylum Tardigrada) from Swaziland. Two samples of foliose lichen collected in 2010 contained nine tardigrade specimens and one egg belonging to five genera and seven species: Echiniscuscf.quadrispinosus,Milnesiumsp., Milnesiumcf.bohleberi, Hypsibiuscf.convergens,Ramazzottiussp., Macrobiotuscf.pallarii andMinibiotusharrylewisi. Milnesiumsp. resemblesMilnesiumlagniappe, a species from southeastern USA, in its cuticle, and possibly in the number of peribuccal lamellae. Specimens from Lesotho and South Africa previously identified asMilnesiumtardigradumare in fact Milnesiumcf.bohleberi. The habitus ofRamazzottiussp. is consistent withR.theroni, a southern African species, but due to the condition of the specimen the presence of cuticular sculpture cannot be definitively ruled out. Macrobiotuscf.pallarii differs fromM.pallariisensu strictoin some structural details of the egg processes. This is the first record ofMinibiotusharrylewisioutside of its type location in KwaZulu-Natal, South Africa.

Intraspecific venom variation in southern African scorpion species of the genera Parabuthus, Uroplectes and Opistophthalmus (Scorpiones: Buthidae, Scorpionidae)

Scorpion venoms comprise cocktails of proteins, peptides, and other molecules used for immobilizing prey and deterring predators. The composition and efficacy of scorpion venoms appears to be taxon-specific due to a coevolutionary arms race with prey and predators that adapt at the molecular level. The taxon-specific components of scorpion venoms can be used as barcodes for species identification if the amount of intraspecific variation is low and the analytical method is fast, inexpensive and reliable. The present study assessed the extent of intraspecific variation in newly regenerated venom collected in the field from geographically separated populations of four southern African scorpion species: three buthids, Parabuthus granulatus (Ehrenberg, 1831), Uroplectes otjimbinguensis (Karsch, 1879), and Uroplectes planimanus (Karsch, 1879), and one scorpionid, Opistophthalmus carinatus (Peters, 1861). Although ion signal patterns were generally similar among venom samples of conspecific individuals from different populations, MALDI-TOF mass spectra in the mass range m/z 700–10,000 revealed only a few ion signals that were identical suggesting that species identification based on simple venom mass fingerprints (MFPs) will be more reliable if databases contain data from multiple populations. In general, hierarchical cluster analysis (HCA) of the ion signals in mass spectra was more reliable for species identification than counts of mass-identical substances in MFPs. The statistical approach revealed conclusive information about intraspecific diversity. In combination with a comprehensive database of MALDI-TOF mass spectra in reflectron mode, HCA may offer a method for rapid species identification based on venom MFPs.

Micro-plastic ingestion by waterbirds from contaminated wetlands in South Africa

Despite a large literature on the impacts of micro-plastic pollution in marine ecosystems, very little research has focused on these pollutants in freshwater ecosystems. Recently, however, a few studies have demonstrated that micro-plastic pollutants are ingested by freshwater taxa, including birds. To explore this potential environmental threat in African freshwater systems we quantified micro-plastic pollutants in the faeces and feather brushings of seven southern African duck species. We analysed 283 faecal samples and 408 feather brushings, and found that 5% of faecal samples and 10% of feather samples contained micro-plastic fibres. The presence and abundance of micro-fibres differed between sampling sites, with significantly higher amounts recorded for the site that received effluent from a sewage treatment facility. Additionally, micro-fibre presence differed across duck species, indicating that foraging behaviour affects plastic ingestion. Our study confirms that African freshwater ecosystems and the biodiversity they support are under threat from micro-plastic contamination.

A taxonomic revision of Schoenus compar - Schoenus pictus and allies (Cyperaceae, tribe Schoeneae) with three new species described from South Africa

A taxonomic revision of the Schoenus compar - Schoenus pictus and allies group is presented, following a recent taxonomic realignment that transferred 24 southern African species into Schoenus from Tetraria and Epischoenus. In light of recent field collections and a thorough review of herbarium specimens, we revise the delimitations and distributions of three species (Schoenus compar, Schoenus arenicolus and Schoenus pictus) and raise Schoenus pseudoloreus to species level from its previous status as a variety of Tetraria sylvatica. In addition, we describe three new species (Schoenus aureus, Schoenus megacarpus and Schoenus filiculmis) predominantly occurring in the Cape Floristic Region of South Africa. Species in this group have either dilated primary inflorescence bracts or membraneous marginal extensions on the bracts that either partially or entirely cover spikes. Moreover, the sheaths and ligules are most often open and membranaceous. We present an identification key for these seven species and update their nomenclature, as well as provide detailed descriptions and distribution maps.

Variable Molecular Markers for the Order Mantophasmatodea (Insecta).

The recently discovered insect order Mantophasmatodea currently comprises 19 Southern African species. These mainly occur in allopatry, have high levels of color polymorphism and communicate via species- and gender-specific vibratory signals. High levels of interspecific morphological conservatism mean that cryptic species are likely to be uncovered. These aspects of Mantophasmatodean biology make them an ideal group in which to investigate population divergence due to habitat-specific adaptation, sexual selection, and potentially sensory speciation. Lack of appropriate genetic markers has thus far rendered such studies unfeasible. To address this need, the first microsatellite loci for this order were developed. Fifty polymorphic loci were designed specifically for Karoophasma biedouwense (Austrophasmatidae), out of which 23 were labeled and tested for amplification across the order using 2-3 individuals from 10 species, representing all 4 currently known families. A Bayesian mitochondrially encoded cytochrome c oxidase I (COI) topology was reconstructed and divergence dates within the order were estimated for the first time. Amplification success and levels of polymorphism were compared with genetic divergence and time since divergence. In agreement with studies on vertebrate taxa, both amplification and variability were negatively correlated with distance (temporal and genetic). The high number of informative loci will offer sufficient resolution for both broad level population genetic analysis and individual based pedigree or parentage analyses for most species in Austrophasmatidae, with at least some loci available for the other families. This resource will facilitate research into the evolutionary biology of this understudied but fascinating group.

The taxonomy of Kalanchoe brachyloba Welw. ex Britten (Crassulaceae)

Summary: The taxonomy of Kalanchoe brachyloba Welw. ex Britten, a common species in the western, central, northern, and eastern parts of southern Africa, and further north to central Africa, is reviewed. Although having affinities with K. paniculata Harv., K. brachyloba is a distinctive species characterised by its sessile, arched, oblong-lanceolate leaves that are lengthwise-folded upwards along the midrib, and have a velvety feel to the surface. The leaf margins are coarsely and irregularly serrate-lobed to crenate, rarely entire as in K. paniculata, which has flat to variously floppily folded, subcircular to broadly ovate leaves. K. brachyloba is one of the few southern African species of which the flowers are twisted below the free portions (lobes) of the petals. An amplified description and a distribution map are provided for the species. The name K. brachyloba is lectotypified, and the typification of several of its synonyms is clarified.

Two new Oxalis (Oxalidaceae) species, including 5 varieties, from the Richtersveld of South Africa

Two new species of Oxalis (Oxalidaceae) from the Richtersveld are described, namely Oxalis canaliculata and O. magnifolia. These widespread species are morphologically distinct and easily identified, but both contain populations in which individuals consistently differ morphologically from typical varieties. The typical variety of Oxalis canaliculata is widespread throughout the Richtersveld, while O. canaliculata var. trifoliolata is known from a single population and O. canaliculata var. graniticola is known only from granite outcrops. Oxalis magnifolia includes the typical variety that is widespread and Oxalis magnifolia var. reduplicata, which is only known from two populations in close proximity to one another. Morphological characters, preliminary phylogenetic position based on data from the nuclear ITS region, habitat description and formal taxonomic descriptions are provided for all taxa. The diagnostic characters of the new species are compared to all phenotypically similar southern African species.

Life-histories explain the conservation status of two estuary-associated pipefishes

Two endemic southern African pipefish species (Teleostei: Syngnathidae) co-occur in estuaries on the southeast coast of South Africa. The larger longsnout pipefish, Syngnathus temminckii, is abundant and has a wide range that comprises coastal and estuarine habitats in all three of the region's marine biogeographic provinces. In contrast, the smaller estuarine pipefish S. watermeyeri is critically endangered, and confined to a few warm-temperate estuaries. Here, we explore reasons for these considerable differences in conservation status. Fecundity is related to fish size, with large live-bearing S. temminckii males carrying up to 486 developing eggs/embryos, compared to a maximum of only 44 recorded for S. watermeyeri. Loss of submerged seagrass habitats due to episodic river flooding appears to be correlated with the temporary absence of both species from such systems. Prolonged cessation in river flow to estuaries can cause a collapse in estuarine zooplankton stocks, a food resource that is important to pipefish species. The greater success of S. temminckii when compared to S. watermeyeri can be attributed to the former species' wider geographic distribution, fecundity, habitat selection and ability to use both estuaries and the marine environment as nursery areas. Genetic data indicate that this has resulted in a much smaller long-term effective population size of S. watermeyeri, a situation that has persisted since the beginning of the present interglacial period. Syngnathus watermeyeri is thus naturally more susceptible to anthropogenic disturbances, which have resulted in an alarming reduction in its contemporary population size. Possible measures to promote the conservation of S. watermeyeri are presented.