The karyotypes of six African Chironomus species (Chironomus alluaudi Kieffer, 1913, Chironomus transvaalensis Kieffer, 1923, Chironomus sp. Nakuru, Chironomus formosipennis Kieffer, 1908, Chironomus prope pulcher Wiedemann, 1830, Chironomus sp. Kisumu) were investigated; four of these karyotypes were described for the first time (Chironomus sp. Nakuru, Chironomus formosipennis, Chironomus prop...

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 averag...

The effects of environmental contaminants (i.e., nonylphenol, bisphenol A diglycidyl ether, benzo[a]pyrene, chlorpyriphos, paraquat dichloride, and lead nitrate) on Chironomus hemoglobin were investigated in the 4th instar larvae of Chironomus riparius (Diptera: Chironomidae), with respect to the total hemoglobin contents, individual globin gene expression, individual globin protein expression ...

Cytochrome P450-dependent aldrin epoxidation was characterized in third instar larvae of the aquatic midge, Chironomus tentans. Optimal in vitro assay conditions for the epoxidase were pH 7.6 and 31 degrees C. Activity was linear up to 40 min of incubation time and 0.5 mg microsomal protein per incubation. The activity was concentrated in the microsomal fraction of whole body homogenates and wa...

Cytochrome P450-dependent microsomal monooxygenase (P450) activity was measured in control and atrazine-exposed third instar midge larvae, Chironomus tentans. Significantly elevated O-demethylase activity was observed in gut homogenates taken from midges exposed to atrazine concentrations from 1 to 10 ppm for 90 h. No significant induction was observed at atrazine concentrations below 1 ppm. A ...

Cytochrome P450-dependent microsomal monooxygenase (P450) activity was measured in control and atrazine-exposed third instar midge larvae, Chironomus tentans. Significantly elevated O­demethylase activity was observed in gut homogenates taken from midges exposed to atrazine concentrations from 1 to 10 ppm for 90 h. No significant induction was observed at atrazine concentrations below 1 ppm. A ...

It has long been assumed that the resistant eggs of many zooplankton are able to survive passage through the gut of migratory waterbirds, thus facilitating their dispersal between isolated aquatic habitats. We present the first evidence that such passive internal transport within birds may be relevant for insect populations. In three out of six faecal samples from black-tailed Godwits on autumn...

Toxicity of three mosquito oviposition repellents, N,N-diethyl-3-methylbenzamide (AI3-22542 or deet), AI3-35765, and AI3-37220 to 6 aquatic nontarget invertebrates, was evaluated in the laboratory. The 24-h LC50 values for Cypricercus sp. (Ostracoda), Moina sp. (Cladocera), Eucyclops agilis Koch (Copepoda), Strelkovimermis spiculatus Poinar & Camino (Nematoda), Þrstand fourth-instar Toxorhynchi...

Squashing salivary glands of Chironomus thummi larvae, Amblystoma tigrinum erythrocytes, or Spirostromum frequently results in stretched chromatin having highly oriented DNA as determined by polarized fluorescence microscopy of acridine orange-stained preparations. The examination of such material from C. thummi in the electron microscope indicates that the individual chromatin fibers have an a...