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The article presents the study which examined the distribution of the Sarophorus diabolus sp. n. and Sarophorus sp. n. (Coleoptera: Scarabaeidae: Scarabaeinae) beetle species from South Africa. Also cited are the physical features of the species like their pronotum, elytra and venter, as well as their etymology, as well as the submission of the specimens to such institutions as the National Collection of Insects, Pretoria, South Africa (SANC).

Invertebrates are essential for ecosystem functioning and have received much attention in biodiversity, conservation and ecological studies. Numerous collection techniques for assessing arthropod diversity exist, but there is little understanding of the consequences of choice of any particular method. This information is essential for project planning and for the interpretation of results. Here we assess sweep netting and suction sampling, two widely used methods for sampling foliage arthropods, and compare them in terms of their efficacy and effort in surveying arthropod biodiversity. Arthropods were collected in paired transects in shrubby fynbos vegetation in the Cape Floristic Region, a biodiversity hotspot. Overall, the vacuum sampling collected significantly more species and individuals than sweep netting, although this was taxon specific. Use of the vacuum sampler significantly increased the time spent in the field per transect and it also collected significantly more dead plant biomass than the sweep net, thus requires a longer period to sort samples afterwards. Sweep netting caused significantly more damage to plants, an important consideration when working in sensitive ecosystems. Assemblage composition of arthropods collected by the two methods were significantly different with only about half of all arthropod species collected shared between the two methods. Our results show that overall, the vacuum sampler outperformed the sweep net in terms of arthropod species richness and abundance and minimising damage to vegetation, but that it takes considerably longer to collect the relevant data. When more representative biodiversity surveying is needed, the use of both techniques is encouraged. [ABSTRACT FROM AUTHOR]

Effective biodiversity monitoring and rehabilitation relies on a good understanding of the factors that influence species distributions and assemblage composition. Here we investigated the influence of plant community characteristics on arthropod diversity, abundance and community composition at the radioactive waste-disposal facility of the South African Nuclear Energy Corporation (NECSA), Northern Cape Province. Plant alpha-diversity and cover was similar between all five plant communities surveyed. Similarly, total arthropod alpha-diversity did not differ between these plant communities. In contrast, arthropod abundance differed between the different plant communities and was negatively correlated with plant alpha-diversity and positively correlated to vegetation cover. Also, more beta-diverse plant communities did not necessarily support greater beta-diversity of arthropods. However, different plant communities generally had different arthropod communities. This highlights the importance of maintaining a mosaic of different plant communities for the effective conservation of arthropod biodiversity in this semi-arid region. [ABSTRACT FROM AUTHOR]

The negative effects of alien invasive plants on habitats have been well-documented. However, the exchange of organisms between these and native taxa has been far less researched. Here we assess the exchanges of arthropod associates of a native ( Virgilia divaricata) and an invasive ( Acacia mearnsii) legume tree within the ecotone between forest and fynbos vegetation within the Cape Floristic Region of South Africa. Arthropod species richness, abundance, species assemblage composition and measures of beta-diversity were assessed between these two legume species where they grow sympatrically. Except for spiders and ants, arthropod species richness did not differ significantly between the two tree taxa. The overall abundance of arthropods was, however, significantly higher on the native tree species. This pattern was strongly driven by herbivores, as is consistent with predictions of the Enemy Release Hypothesis. When excluding rare taxa, over 75 % of all arthropod species collected in this study were associated with both host trees. However, arthropod community composition differed significantly between the two host plant taxa, largely due to differences between their herbivore communities. Arthropod beta diversity was high on the native host, with arthropod communities on the invasive host being much more homogenous across the sampling range. These results indicate that there are numerous exchanges of arthropods between these native and invasive plants. The invasive plant may provide arthropods with a pathway to other habitats between previously isolated native populations. This will have significant implications for biodiversity conservation at the habitat, species and population level. [ABSTRACT FROM AUTHOR]

The floral heads (infructescences) of South African Protea L. represent a most unusual niche for fungi of the economically important genus Ophiostoma Syd. and P. Syd. emend. Z.W. de Beer et al. Current consensus holds that most members of Ophiostoma are vectored by tree-infesting bark beetles. However, it has recently been suggested that mites, phoretic on these bark beetles, may play a central role in the dispersal of Ophiostoma. No bark beetles are known from Protea. Therefore, identifying the vectors of Ophiostoma in Protea infructescences would independently evaluate the role of various arthropods in the dispersal of Ophiostoma. Infructescence-colonizing arthropods were tested for the presence of Ophiostoma DNA using polymerase chain reaction (PCR) and for reproductive propagules by isolation on agar plates. PCR tests revealed that few insects carried Ophiostoma DNA. In contrast, various mites (Proctolaelaps vandenbergi Ryke, two species of Tarsonemus Canestrini and Fonzago, and one Trichouropoda Berlese species) frequently carried Ophiostoma propagules. DNA sequence comparisons for 28S ribosomal DNA confirmed the presence of O. splendens G. J. Marais and M. J. Wingf., O. palmiculminatum Roets et al., and O. phasma Roets et al. on these mites. Two apparently undescribed species of Ophiostoma were also identified. Light and scanning electron microscopy revealed specialized structures in Trichouropoda and one Tarsonemus sp. that frequently contained Ophiostoma spores. The Trichouropoda sp. was able to complete its life cycle on a diet consisting solely of its identified phoretic Ophiostoma spp. This study provides compelling evidence that mites are the primary vectors of infructescence-associated Ophiostoma spp. in South Africa. [ABSTRACT FROM AUTHOR]

Arthropod-mediated dispersal of pathogens is known in many cropping systems but has never been demonstrated for grapevine trunk disease pathogens. Arthropods from vineyards were screened for the presence of pathogens associated with Petri disease and esca using cultural and molecular techniques. The ability of the most abundant pathogen-carrying species to inoculate healthy grapevine vascular tissues was also determined. Millipedes and ants were allowed to associate with a DsRed-Express-transformed Phaeomoniella chlamydospora, after which they were exposed to freshly pruned healthy grapevines under controlled conditions and wounds were monitored for subsequent infection. In addition, the possibility of millipede excreta, commonly found on pruning wounds in the field, to act as inoculum source was determined. A diverse arthropod fauna was associated with declining grapevines and many of these carried trunk disease pathogens. However, spiders, the ant Crematogaster peringueyi, and the millipede Ommattoiulus moreleti were the most abundant pathogen carriers. The ant and millipede species fed on pruning wound sap and effectively transmitted trunk disease pathogens. Millipede excreta contained viable spores of Phaeomoniella chlamydospora and may serve as an inoculum source. Numerous arthropods, including beneficial predators, are potential vectors of grapevine trunk disease pathogens. Our results highlight the need for an integrated approach, including targeted management of ants and millipedes at the time of pruning, to limit the spread of grapevine trunk diseases. [ABSTRACT FROM AUTHOR]