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A L Dyce

Publications and source records attributed to A L Dyce.

At least 19 recordsLinked to original sources
PubMed1994

Afrotropical Culicoides: description and comparison of the pupae of seven species of the Similis supergroup (Diptera: Ceratopogonidae).

The pupae of Culicoides exspectator Clastrier, C. kobae Cornet & Chateau. C. micheli Cornet & Chateau, C. olyslageri Kremer & Nevill. C. ravus De Meillon and C. (Synhelea) tropicalis Kieffer are described and illustrated for the first time, and the pupa of C. similis Carter, Ingram & Macfie is redescribed. All seven species belong to the Similis supergroup; the immature stages of six are found in ground waters while those of C. olyslageri occur in tree holes. A concise key is presented for differentiating the seven species. Short notes on their larval habitats are given. Reference is made to C. accraensis Carter, Ingram & Macfie, also found in tree holes. Available data suggest that pupal morphology can be used to differentiate closely related species; group characters also exist for those species within the Similis supergroup which can be used to separate ground-water species from those utilizing tree holes. Indications are that the pupae are of limited help in resolving the systematic subdivision of the Similis supergroup.

Animals↗
PubMed1991

Phlebotomine sandflies (Diptera: Psychodidae) from caves in Australia.

All three genera of phlebotomine sandflies recorded from the mainland of Australia are represented in collections from caves in Queensland. Phlebotomus (Australophlebotomus) mackerrasi Lewis and Dyce, Idiophlebotomus wellingsae (L. and D.) and Sergentomyia (Parrotomyia) trezkinni L. and D. achieve their biggest known populations in caves. Each has, however, been collected from outside environs. S. (P.) queenslandi (Hill) is most widespread and abundant across the continent and occurs less frequently in caves than in open situations where it is often associated with ground burrowing reptiles. Its occurrence in warmer caves may be linked with larger reptile predators of bats. S. (P.) curvata L. and D. is known as a single specimen from a cave. Hosts for the cave dominants are unknown but the regular concurrence with bats may be indicative. Immature stages of S. trezkinni and S. queenslandi have been recovered from isolated pellets of bat faeces and adults link reared. None of the species has been reared from mass accumulation of bat guano, and none of the species shows special adaptation for life in caves.

Animals↗
PubMed1989

An early record of Culicoides species (Diptera: Ceratopogonidae) developing in the dung of game animals in southern Africa.

The value of the dung of game animals as a larval habitat for Culicoides species was briefly investigated in 1973/74 in the Kruger National Park, Transvaal, Republic of South Africa. A total of 4 species in the subgenus Avaritia was reared, 3 from elephant dung, 2 from zebra dung and 1 from the dung of buffalo. These early studies have recently led to more intensive rearing and a better understanding of the systematics of this subgenus in the Afrotropical region.

Animals↗
PubMed1989

Afrotropical Culicoides: Synhelea Kieffer, 1925, resurrected as subgenus to embrace 10 species (Diptera: Ceratopogonidae).

Synhelea Kieffer, 1925, is resurrected from synonymy to embrace 10 species of Afrotropical Culicoides. C. tropicalis Kieffer, 1913, is the subgenotype. C. vagus is made a synonym of C. dutoiti while apomorphies common to the remaining species camicasi, congolensis, dispar, moucheti, pellucidus, perettii, tauffliebi and vicinus are discussed. The broad similis group of Cornet & Chateau (1971), under which these 10 species of Synhelea were originally assembled, is not only maintained but expanded by a further 11 species. Various distributional and descriptive data pertinent to Synhelea throughout the Afrotropical region are tabulated, and keys to adult males and females presented. C. perettii and C. moucheti are new records for South Africa. C. dutoiti, C. perettii and C. tropicalis are recorded for the 1st time from Malawi while C. dutoiti and C. tropicalis are newly recorded from Botswana and Namibia respectively. Where available, notes on larval habitats are given. Synhelea is considered endemic to the Afrotropical region and is briefly differentiated from the 25 subgenera currently recognized worldwide. Numerous illustrations accompany the diagnosis.

Africa, Eastern↗
PubMed1985

The current taxonomic status of the Culicoides vectors of bluetongue viruses.

In the regions where bluetongue (BT) viruses are known to occur the taxomonic literature is generally adequate for confident identification of the commoner species that are the most likely vectors. Unfortunately in each region there are difficult taxonomic problems in the accurate determination of some proven or potential vectors. These problems involve the so-called imicola and obsoletus groups of the subgenus Avaritia, the variipennis complex in the subgenus Monoculicoides and the schultzei group of the ill-defined subgenus Oecacta. In the imicola and schultzei groups sophisticated taxonomic studies now in progress have been successful in finding useful morphological as well as biological characters for recognition of the vector species. In the variipennis complex morphologically distinct eastern and western populations can be recognized, but their characteristics with respect to ease of colonization and ability to transmit BT virus (BTV) are not yet well known. The taxonomic status of the subspecies of variipennis known to breed in saline and alkaline habitats is still confused and badly in need of detailed study.

Animals↗
PubMed1985

Vectors of bluetongue virus in Australia.

Two of the 5 serotypes of bluetongue virus (BTV) known from Australia have been isolated from field collected insects. Serotype 20 was isolated in 1975 from a mixed pool of 214 insects containing several Culicoides species. Serotype 1 has been isolated from C. (Avaritia) fulvus Sen & Das Gupta collected at Beatrice Hill in the Northern Territory and from C. (Avaritia) brevitarsis Kieffer collected at Peachester in southeast Queensland. All other isolates of bluetongue (BT) group viruses have been made from sentinel cattle. An additional 2 species of the subgenus Avaritia, C. wadai Kitaoka and C. actoni Smith, 1 species of the subgenus Culicoides, C. peregrinus Kieffer and 1 species of the Schultzei group, C. oxystoma Kieffer have been infected in the laboratory. Serotype 20 was transmitted from sheep to sheep by C. fulvus and serotype 1 by C. fulvus and C. actoni. The infection rates established for Culicoides fed on sheep infected with serotype 20 were C. fulvus 62%; C. wadai 11%; C. actoni 2% and C. brevitarsis 0.3%. All species of insects successfully infected are widely distributed in the Oriental region. Attempts to infect species that are restricted in range to the Australasian region have been unsuccessful. The 3 species with highest experimental infection rates: C. fulvus, C. wadai and C. actoni, are confined in Australia to areas with an annual summer rainfall in excess of 800 mm, and do not penetrate to the drier areas where sheep are commercially husbanded. C. brevitarsis is the vector responsible for transmission in the coastal dairying areas, and although it does occur where sheep are reared, it is an inefficient vector. It breeds in discrete cow dung pats on pasture and is more closely associated with cattle than with sheep when the 2 hosts occur together. More than 1 species of Culicoides is responsible for the transmission of BT group viruses in Australia and no BT disease of sheep has been recorded because the more efficient vector species are not present in sheep rearing areas.

Animals↗
PubMed1985

WHO/FAO Working Team Report: entomology.

A summary of the more important concerns of the Working Team with particular reference to bluetongue (BT) virus (BTV), is as follows: With the exception of Australia, the US, and possibly parts of Africa, there are almost no concrete data that could be used to direct control efforts against the responsible vector(s) of BTV in a specific geographic area. In Australia, a broad plan of attack yielded data that showed that members of the subgenus Avaritia are the primary vector species. It has been clearly shown that Culicoides variipennis (Coq.) is the dominant vector species for most of the US. In the Middle East and certain areas of Africa, isolations from possible vector species indicated that C. imicola K., again probably a species complex and belonging to the subgenus Avaritia, is one of the likely vectors. Except for some subgenera, the taxonomy for much of the Culicoides remains in disarray. The subgenus Oecacta for example still remains a catchall for many species. Although a number of proposals have been made for delineating the species of the C. (Monoculicoides) variipennis species complex, none have been initiated because of the lack of funds. The Working Team strongly feels that the lack of definition of important species complexes is the result of short-term planning that does not consider the fact that efficiency can be increased and a great deal of monies saved by directing control toward the specific species or populations thereof that are responsible for a problem.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1984

Isolation of arboviruses from insects collected at Beatrice Hill, Northern Territory of Australia, 1974-1976.

Between October 1974 and May 1976, 57 596 mosquitoes, 169 957 Culicoides, 5923 Lasiohelea and 1043 phlebotomines were collected for virus isolation at Beatrice Hill (lat. 12 degrees 39'S.,long. 131 degrees 20'E.) in the Northern Territory of Australia. A total of 94 viruses belonging to 22 different serological groupings was isolated. The following species of insect yielded viruses which were identified and those viruses marked with an asterisk represent a new record of insect host: Culex annulirostris: Ross River, Kokobera, Barmah Forest, Corriparta, Eubenangee*, Wongorr; Anopheles amictus: Mapputta*; An bancroftii: bovine ephemeral fever*; An farauti: Eubenangee*; An annulipes: Mapputta; Culicoides marksi: Barmah Forest*, Belmont, Eubenangee*, Wallal, Warrego, Leanyer*, Parker's Farm*, Humpty Doo*; C. peregrinus: Beatrice Hill*; C. oxystoma: Bunyip Creek*, Marrakai*; C. pallidothorax: Wongorr*; C. histrio: Thimiri*; Lasiohelea spp.: Humpty Doo*. Pools of mixed species of Culicoides yielded bluetongue, Belmont, CSIRO Village, Warrego and Facey's Paddock viruses. Filter-passing agents not yet identified, were isolated from Cx annulirostris and An bancroftii. As well as providing new locality records for all but one of the 22 viruses isolated, the study yielded five new viruses (bluetongue serotype 20, CSIRO Village, Marrakai, Beatrice Hill and Humpty Doo viruses) and a new record for Thimiri virus which had not been recorded previously in Australia nor had it been isolated from an arthropod. Nine of the viruses isolated occur in more than one family of Diptera.

Animals↗
PubMed1978

Onchocerca sweetae (Nematoda: Filarioidea): notes on the intermediate host.

Microfilariae of Onchocerca sweetae are broadly distributed in the superficial layers of the dermis of the water buffalo (Bubalus bubalis). A total of 2855 insects representing 20 species were collected from O. sweetae-infected bait buffaloes. Only one species, Culicoides sp. "M", ingested microfilariae from buffalo skin. Larval development of O. sweetae was observed in the thorax of this species. Atotal of 829 insects, representing 7 species and including 749 parous Culicoides spp. were collected from light and Manitoba traps. Developing filarioid larvae were observed only in Culicoides sp. "M". It is concluded that Culicoides sp. "M" is a natural intermediate host of O. sweetae in the Northern Territory of Australia.

Animals↗