Orgilus parcus was descriptionbed by R. E. Turner in 1922 from adults collected at Mossel Bay and Ceres in the Cape Province and is presumably indigenous to South Africa. It attacks tuber moth larvae in potato lands in the Transvaal and in the Cape, and probably elsewhere in the country. A descriptionption is given of its life-history and behaviour and of the morphology of the immature stages.
Descriptions and figures are given of the final instar larvae of Dacus ciliatus, D. frontalis and D. vertebratus, three Dacinae which commonly attack Cucurbitae in the Western Cape. The general morphology of these larvae is descriptionbed and discussed. The larvae of D. ciliatus and D. frontalis are very similar in appearance but those of D. vertebratus can easily be distinguished from the other two on account of its size and the number of tubuli on the anterior respiratory organ.
Field studies in the eastern Transvaal and Swaziland citrus areas showed that extremes of weather play a predominant role in regulating population fluctuations of T. erytreae. Populations were consistently the highest in the cool, moist upland region of each study district and were always low and isolated in the hot, arid lowlands. There was a trend for higher populations to develop in mild seasons or following spells of cool, overcast weather during the summer months. The insect favoured well-shaded breeding sites in the lower section of tree canopy, was frequently found in large numbers near windbreaks, and rarely colonized small trees in the hot regions during the summer months.
The subtribe Selenaspidina has been very ably revised by Mamet (1958). Its distinguishing characters are the acute, spur-like development of the third lobes and/or a marked lateral constriction of the prosoma. At hand are a number of very interesting forms which could not be identified and are therefore descriptionbed and named below.
Over the past 15 years the author has been collecting and studying wasps of the genus Cerceris Latreille, 1802 in southern Africa. A large collection has been accumulated and, as familiarity with this large and interesting group was acquired, it became necessary, for the determination of material, to consult authentic representatives of descriptionbed species. Through the kindness of many workers acknowledged below, this phase of the work eventually led to the examination of most of the type material of Arnold, Brauns, Schletterer, Kohl, Cameron, Dahlbom, Smith, Turner and others.
Results have been given from operational research into swarm formation and aerial control of adult Red Locusts (Nomadacris septemfasciata Serville) in the Rukwa Valley outbreak area during 1958-62. Locust populations were relatively small but seasonal variations in aggregation were detected. Swarms were common mainly in March-April and from June to September but could occur in most months.
The Isometopinae represent an isolated subfamily of Miridae. Relationship with the Miridae has been generally recognized, but the presence of ocelli, the vertical head, the two-segmented tarsi, and the distinctive habitus of the isometopids have led many modern workers to treat them as worthy of familial status. Carayon (1958) in a carefully reasoned analysis has shown conclusively that not only do isometopids agree with other Miridae in most essential morphological features but also, as previously recognized, that they comprize a polyphyletic group.
The brown locust is a small species relative to most other plague locusts, but it has a very pronounced phase polymorphism and presents a serious economic problem. In its solitarious phase it occurs over an area of about 100,000 square miles of desert and semi-desert steppe country. This comprises parts of the Cape Province, the Western Orange Free State and the southern parts of South West Africa with an annual summer rainfall of between 5 and 15 inches. During uncontrolled plagues swarms are known to have emigrated and bred at one time or another over most of Southern Africa to as far north as the Zambezi river (Faure, 1932; Lea, 1968).
This bibliography represents the fruits of the collection of literature on African Trichoptera over the past fifteen years. All papers with references to Trichoptera have been included, whether systematic, ecological, zoogeographical or biological. Almost all the literature recorded is either in our hands or has been seen. The items that have not been seen are marked with an asterisk. The bibliography does not claim to be complete and we shall be grateful if readers will send us any references that have been omitted.
This paper presents records and descriptionptions of a few mealybugs and soft scales from cultivated plants, recently submitted for study from various countries from Africa south of the Sahara and from North America. As our knowledge of the soft scales (Coccidae) improves, it becomes more and more evident that the identification and classification of species will to a large extent be based on the glandular structures of the derm, of which there seem to be numerous types.
Nests of Trigona gribodoi and T. beccarii are descriptionbed. T. gribodoi inhabits small hollows in tree trunks and branches. The brood is in clusters, as are pollen pots and honey pots. T. beccarii nests in the ground, in a batumen lined cavity. The brood is in horizontal combs and the whole nest is much as in the related T. tanganyikae. The enormous storage pots are supported by rather numerous long pillars.
During an intensive study on the distribution of some Ephemeroptera in the Komati River system, Eastern Transvaal, some specimens rare to the Transvaal were found. The survey was carried out during the autumn, winter and spring of 1966 and summer of 1966/67.
Odites artigena Meyr. is a minor pest of Coffea arabica in the East Rift area of Kenya. The larvae skeletonize and also eat out irregular holes from within their webs on the under surface of the leaves. The egg, larval, pupal and adult stages are descriptionbed. The complete lifecycle takes about 90 days at 23.5ï¿½C. The most important parasites are Microlycus sp. and Elasmus flaviceps Ferr. Two species of Pediobius are important hyperparasites attacking both Chalcidoid and Ichneumonoid members of the parasite complex.
This paper presents records and descriptionptions of three encyrtids belonging to the genera Clausenia Ishii, Alamella Man Mohan and Gyranusoidea Compere. They are parasitic in economically important, citrus-infesting mealybugs (Homoptera: Pseudococcidae). A new species of Aphidencyrtus Ashmead is descriptionbed which, so far as is known, restricts its attack to primary parasites inhabiting psyllids (Homoptera: Psyllidae). A species of Syrphophagus Ashmead known from the Orient is recorded from a common aphidivorous syrphid fly in South Africa, and the genus Mayrencyrtus Hincks, represented by two species, is recorded from Africa for the first time. Two species of Comperia Gomes are descriptionbed from unreared South African material.