Oviposition and Eclosion Periods of Ixodes didelphidis

Oviposition and eclosion periods for Ixodes didelphidis were observed under two temperatures (25ºC and 27ºC) and 90-95 % humidity. Although there was a significant increase in the eclosion period (p<0.05) and a tendency to increase the oviposition period at 25ºC, there was neither significant differences in the interval (days), until maximum peak of eclosion nor in the number of emerging larvae during the peak nor the total number of emerged larvae. These temperature values are not critical for embryological development of the species. Because at 27ºC and under high humidity the oviposition and eclosion periods are shorter, and the percentage of emerged larvae is higher, we consider this to be the ideal temperature for laboratory studies. Key words: Ixodes didelphidis- oviposition- eclosion- laboratory conditions The most recent studies on Brazilian species of the genus Ixodes, were carried out by Labruna et al. (1997), on the weight of eggs from six ixodid species from Brazil; Barros-Battesti (1998), on the parasitism of Ixodes didelphidis and I. loricatus on small mammals; Barros-Battesti and Knysak (1999), on the geographical distribution of Brazil-ian Ixodes species; Arzua and Barros-Battesti (1999), on the relationship between I. (Multi-dentatus) auritulus and hosts; and Faccini et al. (1999), on the biological characteristics of the non-parasitic phases of I. amarali. Nevertheless, the biology of these species is still unknown. I. didelphidis Fonseca and Aragão, 1951 is a tick species endemic to Brazil, with registered oc