Abundância, riqueza, análise faunística e efeitos da fragmentação florestal em Calliphoridae (Diptera) na Reserva Biológica do Tinguá, Nova Iguaçu, Brasil.

Abstract

Monthly collections were carried out from June 2006 to may 2007, using two traps containing sardine exposed for 48 hours and placed in three different sites: A- on the border (500 m from the entrance of the Reserve); B- 1,200 meters from the entrance and 1,000 meters towards the interior of the woods; C- 1,700 meters from the entrance and 500 meters towards the interior of the woods. A total of 8,516 Calliphoridae of 26 species were collected, most of them females. Sites A and B showed 23 species each and site C, 16. The most abundant species in the different sites were: A- Chrysomya albiceps, Hemilucilia semidiaphana and Chrysomya megacephala; B- Mesembrinella bellardiana, H. semidiaphana and Laneela nigripes and C- L. nigripes, M. bellardiana and H. semidiaphana. Site A showed synanthropic and asynanthropic species. C. megacephala was a constant finding exclusively in site A, and may be considered an environmental indicator of an anthropized setting. Site B showed predominance of asynanthropic species and presence of synanthropic ones. Site C was more preserved and synanthropic species were more constant. Site B showed greater calliphoridae diversity, followed by sites A and C. Populations were considered to be similar in all sites, with the greatest similarity observed between A and B. The ten most abundant species were grouped in patterns in relation to the habitat, with L. nigripes and M. bellardiana isolated, and species in sites A and B arranged in different groups. Most of the constant species collected in the reserve showed a positive correlation with temperature (7 in 13) and negative correlation with humidity (11 in 13). All of them showed negative correlation with precipitation. Humidity showed the greatest (negative) correlation with calliphoridae abundance and precipitation showed the greatest correlation with variety. In the three sites, calliphoridae variety and abundance were similarly correlated with climate variables, showing a negative correlation with precipitation and positive correlation with temperature. September/06 was the month when the greatest abundance and variety of calliphoridae was observed. From the thirteen species constant in Reserva Biológica do Tinguá, seven were synanthropic, evidencing the anthropic effect on this place. Rare (Singletons, Doubletons, Uniques and Duplicates), intermediate and common species were defined; variety and variety projection were calculated for each site (Chao 1, Chao 2, Jackknife 1 and 2, Ace, Ice and Bootstrap estimators); diversity was calculated by means of the Shannon-Wiener diversity index; and evenness was calculated using Pielou s index; similarity between sites was calculated by means of Sorensen s similarity quotient and percentage similarity was calculated by means of Southwood. The number of rare species in site B was similar to that of intermediate and common ones. In sites A and C this number was lower, with a greater number of intermediate species. Jackknife 2 estimator in site B produced greater variety rate, indicating the possibility of collection of other five species in Reserva Biológica do Tinguá, whereas in sites A and C, three other species could be collected. Ace and Bootstrap showed to be more precise for the estimation of the variety of Calliphoridae species. Diversity was greater in site B and evenness was similar in the three sites.