CULICOIDES DA REGIÃO NEOTROPICAL (DIPTERA, CERATOPOGONIDAE). II - OBSERVAÇÕES SÔBRE BIOLOGIA EM CONDIÇÕES NATURAIS

Abstract

The authors give the results of their observations on the biology of Culicoides at São Vicente, State of São Paulo, Brazil. In the first place they describe the region and methods used. In their investigation of breeding places the results were as follows: C. insignis breeds in ditches, salt marshes, in crab holes of Oediplcura cordato; C. maruim was only found in salt marshes; C. guyanensis was found in ditches with o r without saline concentration; C. rcticulatus was found in crab holes o f Cardisoma guanhumi. As to adult behaviour, they give some data on house frequenting habits, blood sucking habits and variations of density. They analyse the influence of tides, concluding that low tides rnay influence the density of some species, chiefly C. maruim. The stational variation of density leads to the conclusion that there is a tendency to decrease in cold and dry months and to increase in humid and warm ones. Nevertheless the authors call attention to the considerable variations which lead us to supose the influence of many other general and specific factors. In the end they give some data on the specific composition of the populations studied. The most common species was C. insignis and the most rare C. maruim and C. guyanensis. A total of ten species was found. The authors also report the locality of São Vicente as the most southern record of C. furens known at present.