Os mosquitos (Diptera: Culicidae) do campus ecológico da UFMG, Belo Horizonte, Minas Gerais

In a small forest of 4ha placed inside the Ecologic Campus of Federal University of Minas Gerais, Belo Horizonte, were made captures of mosquitoes each fifteen days (during the day and the night) in a complete year: March 1988 to February, 1989. The daylight captures were made on human bait and the night captures were made with New Jersey trap. Sixty one captures were made, yielding 497 specimens of 15 species.

On the immature stages of two mosquitoes (Diptera: Culicidae) originally described from Rio de Janeiro, Brazil

The fourth-instar larva and pupa of Psorophora pseudomelanota Barata & Cotrim, 1971 and Phoniomyia deanei Lourenço-de-Oliveira, 1983 are described and compared with those of related species.

Astronotus ocellatus (Cichlidae: Pisces) and Macropodus opercularis (Anabatidae: Pisces) as predators of immature Aedes fluviatilis (Diptera: Culicidae) and Biomphalaria glabrata (Mollusca: Planorbidae)

Two fish species, Astronotus ocellatus (Cichlidae) and Macropodus opercularis (Anabatidae) were tested for predacious behavior toward immature mosquitoes (Aedes fluviatili9s, Diptera: Culicidae) and schistosomiasis snail hosts (Biomphalaria glabrata, Mollusca: Planorbidae), in the presence or absence of non-living food and laboratory conditions. A. ocellatus, a species indigenous to Brazil, was a very efficient predator of both organisms (alpha=1,05); M. operculatis, an exotic species, preyed well on immature mosquitoes, but small snails and snail egg-masses were ingested only irregulary. Both fish species seemed to prefer live to non-living food.

Brazilian dengue virus type 1 replication in mosquito cell cultures

The development of dengue viruses type 1 obtained from accute human sera and inoculated into mosquito cell cultures, was observed by standard transmission electron microscopy and cytochemical staining. It follows the trans-type mechanism already estabilished of other dengue types. Directed passage of single virus particles across the cell membrane seems to be a pathway of entry and exit in dengue-1 infected cells. The nature of numerous electron translucent vesicles and tubules, produced simmultaneously during virus replication inside the rough endoplasmic reticulum, was analyzed by cytochemical tests. The largest amount of virus particles was produced inside cell syncytia.

A new species of Cullex (Melanoconion) from the Amazonian Region (Diptera: Culicidae)

Culex (Melanoconion) eknomios, a new species from Amazonian region is described, including the adult, pupal and larval stages. Available data about distribution and binomics are presented.

Replication of dengue viruses in mosquito cell cultures: a model from ultrastructural observations

Mosquito cell cultures infected with human sera from dengue-1 and dengue-2 outbreaks, started in Rio de Janeiro by 1986 and 1990 respectively, were examined by electron microscopy at different times post the infection of cell cultures. More information was obtained about cell penetration of virus particles in the presence or not of antibodies, their pathway inside the cells, replication mode and exit. Infectiveness of the virus at those different stages can only be attributed to the particles appearing inside the trans-Golgi vesicles; most of all newly formed virus particles remain inside the RER-derived cell vesicles or inside lysosomes, even during cell lysis. Groups of larges particles, 65-75 nm in diameter at dengue-2 infections, persist during cell passage. The large amounts of smooth membrane structures, as vesicles or tabules inside the RER are attributed to a cell response to viral infection.

Scanning electron microscopy of the eggs of two species of Anopheles (Kerteszia) (Diptera: Culicidae)

The eggs of Anopheles cruzii and An. bellator are described and illustrated using scanning electron micrographs. Hatching was observed, and larval exit documented. No morphological differences were found between the eggs of the two species.