In this paper we describe a method for the rapid mass isolation of polytene nuclei from Chironomus salivary glands. The procedure for the isolation of glands involves 5 principal steps; (a) freezing Chironomus larvae in liquid propane; (b) breaking open frozen animals in a pre-cooled mortar; (c) thawing the fragments in sucrose medium, free of divalent cations; (d) pressing the suspension of br...

Early life stages of aquatic organisms tend to be more sensitive to various chemical contaminants than later life stages. This research attempted to identify the key biological factors that determined sensitivity differences among life stages of the aquatic insect Chironomous riparius. Specifically, second to fourth instar larvae were exposed in vivo to both low and high waterborne concentratio...

In contrast to bird flocks, fish schools and animal herds, midge swarms maintain cohesion but do not possess global order. High-speed imaging techniques are now revealing that these swarms have surprising properties. Here, I show that simple models found on the Langevin equation are consistent with this wealth of recent observations. The models predict correctly that large accelerations, exceed...

Four new species of predaceous midges of the genus Parabezzia Malloch are described and illustrated based on female specimens from southeastern Brazil. Two species are recorded for the first time from Brazil, Parabezzia costalis Wirth from Rio de Janeiro State and P. balseiroi Spinelli & Grogan from Rio Grande do Sul State. 

Toxicity of a phenyl pyrazole insecticide, fipronil, to 4th-instar larvae of 6 species of colonized mosquitoes (Aedes aegypti, Ae. albopictus, Ae. taeniorhynchus, Anopheles quadrimaculatus, Culex nigripalpus, and Cx. quinquefasciatus) and 2 species of field-collected chironomid midges (Chironomus crassicaudatus and Glyptotendipes paripes) was evaluated in the laboratory. All mosquito species we...

objective: the orange-red spectrum of  the skin of  electric yellow (labidochromis caeruleus) is  one  of  the  idealistic and  necessary  schemas sought  by  aquarists  and commercial producers. in this study, the effect of live foods meal on the skin coloration of juvenile electric yellow was examined. methods: 270 fish with an average living body weight was 0.42 ± 0.11 g, and average total l...

The fine structures of nuclear envelopes known to have different permeability properties were compared. Membranes of salivary gland cell nuclei of Drosophila (third instar) and Chironomus (prepupae), which are strong barriers to ion diffusion, and membranes of oocyte nuclei (germinal vesicle) of Xenopus and Triturus, which are much more ion-permeable, show no essential difference in size, frequ...

Macrobenthic fauna have recently been widely used as bio-indicators for their ability to reflect the various disturbances in aquatic ecosystems. They assess ecological health of streams East Cameroon region. This study aims reveal four by studying variations population benthic macroinvertebrates collected them. Sampling was done from December 2018 2019 a total 13 months spread over collection s...

Patterns of abundance and distribution of chironomid midges (Diptera, Chironomidae) in the middle Rio Doce basin were analysed. Human activities (mining, steel processing, and Eucalyptus spp. forestry) contribute to environmental degradation and low water quality in this watershed. Physical and chemical water traits (dissolved oxygen, pH, total alkalinity, electric conductivity, phosphorus and ...