The importance of Paracoccus burnerae has risen over the years to an extent where it is now not only a serious pest of citrus, but is also a quarantine pest for citrus fruit imported from South Africa. The field biology of P. burnerae on citrus in the Western Cape Province of South Africa was studied through periodic sampling of leaves from twigs enclosed in sleeve cages. The species composition and abundance of natural enemies was investigated. Both adult and immature stages attained maximum population peaks in March and P. burnerae had four generations. The highest level of mortality was experienced in the immature stages. Climate and an unidentified fungus were the key mortality factors. The level of abundance of the two observed predators, the harlequin beetle, Harmonia axyridis, and the green lacewing, Chrysoperla sp., was relatively low. Although parasitism occurred in some cages, the level was low, ranging between 1.62 and 9.43 %. If biocontrol is the preferred method of controlling P. burnerae, suitable candidate parasitoids for inoculative biocontrol are Acerophagus sp., Leptomastix sp. and Microterys nietneri. The oleander mealybug does not share the same parasitoids with Planococcus citri, Pseudococcus calceolariae and Pseudococcus longispinus except for the parasitoid Coccophagus sp. The most popular species of parasitoids used in the biolological control of mealybugs, Anagyrus sp. and Coccidoxenoides sp., were insignificant in the case of P. burnerae.

Plant-based insecticides may serve as suitable alternative as biocontrol techniques in the future. The present study has explored the effect of ether extracts of Emblica officinalis, Ricinus communis, Acacia coucinna, Cinnamomum tejpata, Piper nigrum, Coriandrum sativum, Olea vera, Linum usitatissimum, Syzygium aromaticum and Nigella sativa against larvae of Aedes albopictus under laboratory conditions. Larvae were exposed to a range of concentrations of each extract. The larval mortality was assessed after 24 and 48 hours exposure and LC₅₀s were calculated for each time interval. All extracts showed moderate larvicidal activity. The lowest LC₅₀ was found in Coriandrum sativum, Nigella sativa and Syzygium aromaticum at a dose of 363.7 ppm, 377.5 ppm and 403.4 ppm, respectively, after 24 h exposure while the amount of extracts used reduced to 263.9 ppm, 300.8 ppm and 342.2 ppm, respectively, after 48 h. In terms of lethal time response again Coriandrum sativum, Nigella sativa and Syzygium aromaticum showed less time to produce 50 % mortality (14.28, 17.77 and 17.99 h). These plants extracts are therefore promising as alternative to synthetic insecticides in mosquito control programmes. Thus providing the basis to use the plant extracts against Aedes albopictus.

A remarkable collection of 298 Gambian Asilidae collected by William F. Snow between 1974 and 1977 and housed in the collections of the Oxford University Museum of Natural History was recently reported upon (Londt 2010). Another collection comprising 196 specimens, collected by Snow from 1969 to 1973, became available for study and the results are reported here. A new species, Sphagomyia gambia, is described and many new records for previously listed species supplied. Nine species are recorded for the first time and a complete list of Gambian Asilidae is provided. With 68 species, The Gambia has West Africa's richest recorded asilid fauna.

Tuta absoluta (Meyrick) is considered the major pest that attacks tomato in many countries. Some insecticides (indoxacarb, imidacloprid) and non-traditional methods (culture filtrate of Bacillus thuringiensis, Artemisia cina extract, clove oil and nanosilica) were evaluated against T. absoluta in tomato under greenhouse conditions. Furthermore, GC-MS analysis was carried out to identify the chemical components of B. thuringiensis culture filtrate as well as A. cina and clove oil extracts. Nanosilica was the most effective treatment against T. absoluta followed by A. cina, imidacloprid A. cina, indoxacarb, filtrate of B. thuringiensis, imidacloprid, indoxacarb A. cina and clove oil treatments, respectively. The mixing of the tested insecticides with A. cina improved the efficiency against the tested insect relative to using insecticides alone. The results suggest possible use of the tested natural products and nanosilica as alternatives for T. absoluta control. Also, this study suggests the possible mixing of the A. cina extract with the tested insecticides to minimize health risk and environmental pollution.

The maize stem borer, Busseola fusca (Fuller) (Lepidoptera: Noctuidae), is of economic importance throughout sub-Saharan Africa. The seasonal activity pattern of this pest is characterized by two to three distinct generations during spring and summer followed by a diapause period of approximately six months during autumn and winter. Genetically modified Bt maize (MON810) that expresses an insecticidal Cry1Ab protein has been deployed in South Africa since 1998 to manage stem borers. The first report of field resistance of B. fusca to Bt maize was made during the 2006 cropping season. Resistant strains of this pest are expected have reduced fitness compared to susceptible individuals. Information regarding fitness of resistant individuals that survive on Bt maize could contribute to the understanding of resistance evolution as well as to development of improved resistance management strategies. Life history parameters of different B. fusca populations were compared in a laboratory study using diapause (spring) as well as second-generation (summer) populations. Sex ratio, pupal mass, fecundity and longevity of moths of field-collected Bt-resistant and susceptible B. fusca populations were compared. Slight adverse effects of Bt maize on fitness of the resistant summer-population were observed. The sex ratio was biased towards males in some resistant populations and towards females in susceptible populations. The resistant population had a lower mean pupal mass, shorter longevity of moths and reduced fecundity.

Leucaena leucocephala (Lam.) de Wit (Fabaceae), an agroforestry tree with invasive properties, was targeted for biological control in South Africa. The seed beetle Acanthoscelides macrophthalmus (Schaeffer) (Chrysomelidae: Bruchinae) was released in 1999 to curb its excessive seed production without negating its beneficial properties. The adult beetles oviposit on the seed pods and loose seeds of L. leucocephala and the hatching larvae enter the seeds and destroy them during their development. Although the beetle has become widely established in South Africa, its contribution to the weed's management is unknown. The aims of this pilot study were to assess: (i) the levels of seed damage inflicted by A. macrophthalmus on L. leucocephala populations and; (ii) the extent to which the endophagous immature stages have recruited native parasitoids. The study was carried out over seven months at three sites in the KwaZulu-Natal coastal region, where L. leucocephala is abundant. Mean seed damage was inconsistent, with considerable variation (2–62 %) between sites and time of collection. On average, <30 % of available seeds was damaged at each site. Five species of parasitoids (Hymenoptera: Chalcidoidea) were consistently reared from beetle-damaged seeds, two of which (both Pteromalidae) were most commonly associated with the beetles. Mean mortality resulting from parasitism was similarly inconsistent and variable (1–22 %) between sites and time of collection. Although parasitism increased with increased seed damage, on average only 7–9 % of larvae/pupae were parasitized at the three sites. The modest levels of seed damage recorded in this study appear insufficient to regulate populations of L. leucocephala in South Africa.

Two-year field trials were conducted to evaluate the role of spacing in managing flea beetle, Podagrica sp., infestation in two okra cultivars. Three seeds were planted per hole and later thinned to one seedling per hole at two weeks after planting (WAP). The four planting spacings used were 60 × 70 cm, 60 × 60 cm, 60 × 50 cm and 60 × 40 cm. The experiment was replicated three times and conducted using split plot fitted into a randomized complete block design with planting spacing as main treatment and cultivars as sub-treatment. The okra cultivars planted at close spacing of 60 × 50 cm and 60 × 40 cm had a significantly (P < 0.05) lower pods length and high mean leaf area damage. The highest mean number of flea beetles (24.50 and 23.17) were from the okra cultivars Jokoso and NH-Ae 47-4 planted at the closest spacing of 60 × 40 cm. Cumulative of the two planting seasons, the highest yield per plant (138.17) was obtained from plots planted at 60 × 70 cm with the okra cultivar NH-Ae 47-4. It was however, not (P > 0.05) higher than yield/plant (129.17 g) from plots planted at 60 × 60 cm. In both seasons and cumulatively, a significantly (P < 0.05) lower pod yield per plant was obtained from plots planted at closest plant spacing of 60 × 40 cm. Irrespective of cultivar, okra planted at close spacing of 60 × 50 cm and 60 × 40 cm were significantly (P < 0.05) taller than okra in other plots. Cumulative of the two seasons, the number of pods (22.95), length of pod (6.71), number of leaves (8.96) and yield/plant (118.25 g) were significantly (P < 0.05) lower in Jokoso. Planting okra at planting spacing of 60 × 70 cm or 60 × 60 cm could manage the population of flea beetle, minimize damage to leaves and guarantee optimum yield from planted okra.

Ovulation, fertilization and both normal and arrested embryonic developments in scorpions, are reviewed and discussed. The importance of all three aspects in scorpion reproduction is discussed from both an evolutionary and an ecological outlook. The number of embryos varies within and among scorpion species and is not related to the female's mass prior to parturition. There is a certain loss in embryo numbers and not all of them will become juveniles. The significance of this loss is discussed, and future avenues of research are suggested.

The brown mite, Bryobia rubrioculus Scheuten thrives on sweet cherry, sour cherry and plum orchards of Hamedan in the western region of Iran. Development and fecundity of this mite was studied on sweet cherry at nine constant temperatures (15, 17.5, 20, 22.5, 25, 27.5, 30, 32.5 and 35 °C), 60 ± 5% relative humidity and a photoperiod of 16:8 h (light:dark). The developmental time from egg to adult ranged from 43.4 ± 0.63 days at 15 °C to 14.5 ± 0.37 days at 32.5 °C. The average longevity of adult females was 14.0 ± 0.88 days at 15 °C to 6.5 ± 0.67 days at 32.5 °C The highest and lowest mean number of eggs laid by a female during life time was 13.8 ± 1.07 and 4.4 ± 0.88 at 20 and 32.5 °C, respectively. These results may be used to predict B. rubrioculus development and population fluctuations.

Cat's claw creeper, Macfadyena unguis-cati (L.) Gentry (Bignoniaceae), introduced as an ornamental plant, has invaded several ecologically sensitive habitats in the higher rainfall regions of South Africa. Biological control was initiated with the release of the leaf-feeding tortoise beetle Charidotis auroguttata (Boheman) (Coleoptera: Chrysomelidae) in 1999. Although established at several field sites, population densities of the beetle have remained low with no assessment of impact to date. However, simulated herbivory studies in Australia revealed that severe and repeated defoliations could slow the weed's growth rate and its accumulation of biomass in the subterranean tubers. The aim of this study was to quantify the impact of medium (50 %) and high-intensity (100 %) defoliations by C. auroguttata, in relation to equivalent simulated damage, on the growth and biomass accumulation of M. unguis-cati. The trials were monitored for 16 weeks with repeated defoliations at two-week intervals. Despite considerable variation in the response variables, plants that were defoliated by C. auroguttata, but not those defoliated mechanically, displayed reduced growth rates. However, significant decreases in stem length and numbers of nodes were demonstrated only after high-intensity beetle defoliations. Despite reductions in tuber biomass in the beetle-defoliated treatments, the differences were not significant, while only high-intensity beetle defoliations caused a significantly lower accumulation of total plant biomass. Simulated herbivory was a poor predictor of insect damage in this study which suggested that C. auroguttata could prove damaging to M. unguis-cati, but only at high population densities. However, in field situations, synergism with a range of additional environmental stressors may increase the negative impact of feeding damage.

Effect of six different diets on the development and oviposition of Harmonia axyridis was studied. The developmental time of larvae fed on different diets ranged from 9.3 to 16.2 days, and the artificial diet-grown larvae showed a significantly longer developmental time than those fed on Sitotroga cerealella eggs or Chaitophorus populeti. They also showed a lower adult emergence rate, which were only 3.6% to 16.0 %, while it was 90.0 % on C. populeti and 72.1 % on S. cerealella eggs. The C. populeti was the best diet in terms of reproduction, because of the shorter pre-oviposition period and higher fecundity of its females compared to the females on artificial diets and S. cerealella eggs. In order to evaluate the potential of S. cerealella eggs for rearing H. axyridis as a supplementary prey, its effect on the fecundity of H. axyridis was tested. The results revealed that for adults fed on C. populeti, their larval food source had no significant effect on duration of pre-oviposition period (8.6 and 7.5 days) and fecundity (737.2 and 739.8). However, when the ladybeetles were fed with C. populeti as larval food and S. cerealella eggs as adult food or S. cerealella eggs alone, the fecundity of H. axyridis dramatically decreased. These results suggest that S. cerealella eggs only can be used as supplementary diet for H. axyridis larvae when natural prey is inadequate or absent, and the artificial diets in this paper show low values.

The increasing pest status of the bollworm, Helicoverpa armigera (Hübner) in South Africa, has prompted renewed interest in the use of bio-insecticides, especially as resistance is suspected to be developing against commonly used pyrethroids. Three entomopathogenic fungi, Beauveria bassiana (Balsamo-Crivelli) Vuillemin, Nomuraea rileyi (Farlow) Samson and Isaria fumosorosea Wize were compared in laboratory bioassays employing topical versus per os inoculation techniques. At a dose of 3.75 × 10⁵ conidia per larva, N. rileyi out-performed both I. fumosorosea and B. bassiana, causing a mean of 87 ± 1.4 % mortality. Following treatment of larvae the proportional mortality among larvae and pupae was generally biased towards pupae with (pooled) treatment mean mortalities of 28 ± 8 % vs 56 ± 18 %, respectively. Notably, no difference was detected between the two inoculation techniques employed with any of the three fungal species assayed. The incubation periods for topical applications ranged from 4 days (PPRI 7201 and 8072) to 7 days (PPRI 7758) while per os treatments responded on Day 4 (PPRI 8072) and Day 5 (PPRI 7758 and 7201) post-inoculation. A general trend of accelerated pupation following treatment with N. rileyi was noted with both inoculation techniques. A novel per os inoculation substrate was tested that ensured more accurate dose acquisition and performance quantification. Compared to the other fungi, superior performance by N. rileyi underscores the potential of this species for development as a myco-insecticide against H. armigera.

Females of the pollinator fig wasp Elisabethiella baijnathi Wiebes carry mites (Tarsonemella sp. nr. africanus) and nematodes (Parasitodiplogaster sp.) between figs of Ficus burtt-davyi in Grahamstown, South Africa. The mites are phoretic on the outside of the wasps and phytophagous, feeding on galled flowers. The nematodes are transported inside the wasps and eventually eat them. Both mites and nematodes were present throughout the year. The prevalence (fig occupancy rates) of mites and nematodes in different crops ranged between zero and 100 %. Crop size did not influence the prevalence of either mites or nematodes. Contrasting dispersion patterns and relationships with fig wasp foundress numbers indicate that the mites, but not the nematodes, disperse between figs after being carried there by the pollinators, and they may also utilize non-pollinating fig wasps as vectors.

Deliberately introduced for agroforestry, the invasive tree Leucaena leucocephala (Lam.) de Wit (Fabaceae) is naturalized in several countries worldwide, including parts of South Africa. The seed beetle Acanthoscelides macrophthalmus (Schaeffer) (Chrysomelidae: Bruchinae) was inadvertently introduced to several countries via contaminated seed, but was released as a biological control agent in South Africa. Although widely established in South Africa, its efficacy may be curtailed because damage is reputed to be confined to canopy-held seeds, with dehisced seeds escaping damage on the ground. To clarify the beetle's potential, we investigated: (i) its selection of oviposition sites when presented with pods bearing seeds, loose seeds and empty pods in different locations (canopy-versus ground-held); and (ii) the effect of seed location on egg mortality. The beetles oviposited on pods bearing seeds, loose seeds and empty pods in both locations but showed significant preferences for pods bearing seeds, regardless of location. Egg mortality was high (66% overall) and caused largely by predation, but did not differ between canopy- and ground-held seeds. Dehisced seeds are thus more likely to escape damage due to the beetle's greater association with pods bearing seeds, which occur mostly in the canopy. While not affected by seed location, egg predation could affect beetle population densities. Although oviposition patterns and egg predation may constrain the efficacy of A. macrophthalonus, seed damage in relation to seed availability still needs to be quantified in the field.

A new species, Anacharis madagascarensis sp. n. is described from Madagascar, which represents the first record of an Anacharitinae from the country and the second record of this subfamily in Africa. The description and diagnostic characters of the new species are illustrated and discussed.

Three new species belonging to two genera of the family Braconidae (Hymenoptera) are recorded from a dipterous aquatic leaf miner on Lagarosiphon major (Hydrocharitaceae): Ademon lagarosiphonae sp. n. (Opiinae) and Chaenusa anervata sp. n. and C. seminervata sp. n. (Alysiinae: Dacnusini). The genera Ademon Haliday, 1833, and Chaenusa Haliday, 1839, are new for the fauna of South Africa.

Preliminary results of studies on ground beetle communities inhabiting semi-arid environments in eastern Algeria are reported. In total, 49 taxa have been collected in a cultivated area and in a natural steppe area. The undisturbed area shows higher species diversity, a slightly higher Shannon index, lower species turnover in two consecutive years, a lower percentage of opportunistic mixophytophagous species, more specialized or generalistic predators and several indicators of higher water content of the soil. In the cultivated area there are more psammophilic elements, lower individual density and population phenology which reflects marked summer aridity, whereas in the natural area summer activity of the beetles may occur. The characteristics of these eastern Algerian open land communities are discussed and compared with some European and African studies.

The larvae of Trioza bullatae sp. n. from the Western Cape Province, South Africa, induce conspicuous globular galls on the leaves of black stinkwood (Ocotea bullata, Lauraceae), a highly valued timber species. The new species is described, illustrated and compared to the Trioza anomalicornis group and Trioza tangae with which it may be closely related. Information is provided on the galls and their development.

Analyses of material collected recently and considerations of biogeographic coherence support the formation of a Porphyronota carnifex species-group, comprising four separate entities. Thus, the previously known P. carnifex s. str. is now subdivided into P. carnifex (Fabricius), with an exclusive northwestern Cape distribution, and P. variegata (Boheman, 1857), with a broader eastern, circum-Drakensberg distribution. The elevation to species level of P. carnifex rougemonti Holm, 1990 from Ethiopia, as proposed earlier by Antoine in 2004, is supported. Porphyronota carnifex tottenhami Holm, 1990 from Angola is also recognized as a proper species, on the basis of several diagnostic characters including a completely black head in both sexes, a great reduction of the paler areas on the abdominal sternites and a poor lateral extension of the ventral lobes of the aedeagal parameres..

This review of parasitoid—plant associations brings new information derived from parasitoid material reared from determined aphid—plant associations. The species are reviewed together with a respective reference list. A comparison with the related western and eastern Mediterranean areas is presented. The updated interactions between Algeria and the southern areas of Western Europe are compared and exemplified by Diuraphis noxia (Kurdjumov) and Lysiphlebus testaceipes (Cresson), both of which are exotic parasitoids that are now considered naturalized species. Some new associations of economic importance are emphasized; among them, a high level of parasitization of Aphis illinoisensis Shimer, a new exotic pest of grapes by L. testaceipes, is the most important.

A comparative study was undertaken to determine progeny development of Dermestes frischii Kugelann and its damage on 12 smoke-dried fish species. The highest weight of the emerged F₁ adult D. frischii was observed in Mormyrus delicosus (0.10 g) followed by Clarias sp. and Malapterurus sp. (0.07 g); while Channa sp., Auchenoglanis sp. and Moronyrus rumi had the least weight of emerged adults (0.01 g). Clarias sp. and Mormyrus delicosus had significantly (P < 0.05) higher number of emerged F₁ adults compared with the number of emerged adults in other species except Malapterurus sp. and Lates niloticus. The significantly (P < 0.05) longest day to first adult emergence (24 days) was observed in Lates niloticus. The least percentage weight loss (20.52%) due to D. frischii infestation was observed on Channa sp., which was significantly (P < 0.05) lower than 73.68% observed in Malapterurus sp. and 71.23% observed in Alestes sp. There was a positive correlation between adult progeny and weight of emerged adult (r = 0.92, P < 0.01). Also, fish bone weight was positively correlated to percentage weight loss (r = 0.87, P < 0.01).