Guild composition and seasonal distribution of insects on Protea magnifica and P. laurifolia (Proteaceae)

Insects were collected over a period of 12 months from Protea magnifies and P. laurifolia by beating. Analysis of guild composition showed remarkable uniformity in proportion of species in different guilds on the two plants. Proportions of individuals in different guilds were not uniform, owing to a larger proportion of phytophages being collected on P. magnifies. A distinct seasonal distribution in insect numbers was observed in four out of six study sites, with peak numbers being collected in summer

THE ASTEROLECANIIDAE (HEMIPTERA: COCCOIDEA) OF SOUTH AFRICA

THE ASTEROLECANIIDAE (HOMOPTERA: COCCOIDEA) OF SOUTH AFRICA The 16 species of Asterolecaniidae known from South Africa can be tentatively placed in six genera based on the characters of the adult female. Some species do not fit into these genera as presently defined, requiring a redefinition of some genera or the creation of new ones. However, it appears that the characters on which the genera of the Asterolecaniidae are presently based are too few in number and unreliable, making a detailed study of other characters of the female and eight other stages necessary for a better understanding of the relationships within this family. Key words: pit scales, taxonomic characters, taxonomy, Abditococcus, Asterodiaspis, Asterolecanium, Bambusaspis, Planchonia, Russellaspis, Amorphococcus acaciae

FECUNDITY, SIZE AND DISPERSAL OF THE WHITE WAX SCALE, CEROPLASTES DESTRUCTOR NEWSTEAD (HEMIPTERA: COCCIDAE), IN THE WESTERN CAPE PROVINCE OF SOUTH AFRICA

FECUNDITY, SIZE AND DISPERSAL OF THE WHITE WAX SCALE, CEROPLASTES DESTRUCTOR NEWSTEAD (HEMIPTERA: COCCIDAE) IN THE WESTERN CAPE PROVINCE OF SOUTH AFRICA. Ceroplastes destructor Newstead has recently attained pest status in areas of South Africa where citrus is grown, particularly on Citrus reticulata in the Western Cape Province. The fecundity, fertility and dispersal of C. destructor were studied as part of a comprehensive overview of its morphology, biology and population dynamics, with the aim of providing a more informed basis for control programs. Fecundity varied significantly both between orchards (P0.01) and between individual females from the same orchard (P0.001). Female body-size also differed between orchards (P0.05) and was positively correlated with fecundity (r2=0.84). The oviposition period was longer for large individuals. No differences in fertility were found between orchards (P0.05). Dispersal was by 1st-instar nymphs, mainly on air-currents, and the numbers caught on a series of sticky traps up to 4m from the source were very similar, suggesting that wind dispersal was very efficient. The numbers caught appeared to be positively correlated to the initial population. The population of 2nd-instar nymphs on the seedlings after 6 weeks was smaller after an initially heavy infestation than on those initially more lightly infested. Key words: hosts, incubation period, Psidium quajava, Ponocirus trifoliata, Eugenia malaccensis, Gardenia thunbergia

Insect diversity in the Cape Floristic Region

The Cape Floristic Region (CFR) is characterized by exceptionally high plant species richness and it is yet to be determined whether this is matched by an equally high diversity of insect fauna associated with these plants. In an attempt to do this, data from the literature on the number of insects for various taxa found at different sites in the CFR were compared with equivalent data from other areas in South Africa and elsewhere. Results indicate that the herbivorous insect fauna of the CFR is not particularly rich in species, perhaps except for the small guild of endophagous insects. It is speculated that this is the result of CFR vegetation being a poor food source for herbivores, particularly in view of its sclerophyllous nature. Plant defence mechanisms, such as a pronounced cyanogenic ability of the leaves coupled with the relatively simple architecture of the plants are possible contributing factors.Articl

Native insects expanding their ranges and becoming more abundant [2]

[No abstract available]Lette