Michele da Costa Pinheiro

Streblidae (Diptera) on bats (Chiroptera) in an area of Atlantic Forest, state of Rio de Janeiro

Because of the few records of Streblidae on bats, despite extensive study on these mammals in the state of Rio de Janeiro, a survey was carried out in an area of Atlantic Forest, in the municipality of Nova Iguaçu, known as the Tinguá region. Thirteen species were added to the list of Streblidae in the state of Rio de Janeiro, of which two were new records for Brazil. Thirty-one species have now been reported this state.

Composition of bat assemblages (Mammalia: Chiroptera) in tropical riparian forests

Various studies have focused on the richness and abundance of bats in tropical forests and how the composition of these forests affects bat assemblages, but there are few studies on the relationship of bats with riparian forests. The aim of this study was to ascertain the differences among bat assemblages of three riparian forest areas of the Tingua region, state of Rio de Janeiro, Brazil. These areas were: I) an agricultural area (Takume); II) a reforested area in primary succession (Canavarro); and III) an area with late secondary vegetation (Tingua Biological Reserve). Assessments of bat species composition in these areas may shed light on how anthropogenic modifications in riparian forests can influence local bat assemblages. Bats were captured with mist nets during 72 sampling nights. Total bat abundance was 1,511 individuals in 26 species. The three areas differed in their species composition. The Tingua Biological Reserve was the richest area, Canavarro presented the lowest diversity and the highest abundance of individuals, and the evenness index was highest in Takume. The differences found in the composition and ecological indices indicate that bat assemblages have distinct characteristics in the three areas studied, with varied degrees of transformation and anthropization.

Ticks on birds caught on the campus of the Federal Rural University of Rio de Janeiro, Brazil

The prevalence of parasitic infections, particularly those caused by ectoparasites, may influence the biology and ecology of wild birds. The aim of this study was to investigate occurrences and identify the species of ticks collected from wild birds caught on the campus of the Federal Rural University of Rio de Janeiro. The birds were caught using mist nets between October 2009 and December 2010. In total, 223 birds were caught, represented by 53 species and 19 families in nine orders. Nineteen birds (n = 7 species) were parasitized by immature ticks (prevalence of 8.5%). Forty-four ticks were collected, of which 23 were nymphs and 21 were larvae. There were associations between parasitism by ticks and non-Passeriformes birds, and between parasitism and ground-dwelling birds, which was possibly due to the presence (or inclusion among the captured birds) of Vanellus chilensis (Charadriiformes: Charadriidae). All the nymphs collected were identified as Amblyomma cajennense. In general terms, we must emphasize that wild birds in the study area may play the role of dispersers for the immature stages of A. cajennense, albeit non-preferentially.

Amblyomma auricularium (Acari: Ixodidae): underwater survival of the non-parasitic phase of feeding females

To determine the effects of immersion in water on the biological parameters of engorged females of the tick species Amblyomma auricularium, 60 females were distributed in six groups, each comprising 10 individuals. The control group - G1 (not immersed) was fixed dorsally in a Petri dish and incubated at 27 ± 1°C and 80% RH. The other groups were subjected to immersion periods of 24, 48, 72 and 96 hours, and the sixth group to continuous immersion. After the immersion period, the females were placed in Petri dishes to begin laying. Eggs were collected every 72 hours and kept in biological chambers. All the groups showed significant differences (p <0.05) during the pre-oviposition period. The laying period and the average weight of overall posture did not change. The egg incubation period also did not differ significantly, but the hatching rate in the group immersed for 96h showed a significant difference. Thus, immersion for up to 96 hours does not impair the survival of A. auricularium females, although it may delay egg laying and reduce the number of offspring.

Free-living ixodid ticks in an urban Atlantic Forest fragment, state of Rio de Janeiro, Brazil

As a consequence of the importance of ticks in forests in protected areas, was conducted survey of species of free-living ticks in the Natural Park Municipal Curió, state of Rio de Janeiro, Brazil. Monthly samples were taken by dragging method, dry ice traps and visual search in two transects. Adults and nymphs of Amblyomma cajennense (n= 147), Amblyomma brasiliense (n= 4) and Amblyomma parvum (n= 1) were collected. This is the first occurrence of A. parvum in the state. No correlation was found between the abundance of stages of A. cajennense and rainfall, temperature and relative humidity. The highest abundances of adults were in the months of January and May, and nymphs in September and October. The low diversity of parasites on Curió Park can be attributed to the proximity of households with pets, which would also explain the higher abundance of A. cajennense that is commonly found in areas impacted by anthropogenic pressure.

Prognosing the sex of adults of Amblyomma auricularium through evaluating the biological parameters of engorged nymphs.

Maintaining tick colonies under laboratory condition, as well as carrying out experimental studies on these arthropods may be more successful with better knowledge of some basic biological parameters. In this study, we evaluated how the weight, engorgement period and premolt period of Amblyomma auricularium nymphs (N=600) correlated with the sex of the adults that subsequently emerged. The experiment was carried out in the W.O. Neitz Parasitological Research Station, Ixodology Laboratory of the Department of Animal Parasitology, Federal Rural University of Rio de Janeiro, located in Seropedica, state of Rio de Janeiro. The average weight of the nymphs was 5.1±1.51mg among those that originated males and 8.2±2.5mg among those that originated females. The engorgement period for the nymphs that originated males was 8.3±1.5days while it was longer for the nymphs that originated females, with an average of 8.8±1.8days to complete their diet. The premolt period was shorter for nymphs that originated males (17.2±0.93days) than for nymphs that originated females (17.7±1.00days). Despite an area of overlapping between the weights of engorged nymphs that originated adult males and females, this is the most reliable parameter for predicting the sex of adults of A. auricularium.

Amblyomma nodosum (Neumann, 1899): observations on life cycle under laboratory conditions

The natural hosts of Amblyomma nodosum in the immature stages are a variety of birds and the anteater in the adult stage. However, so far no data have been published about this ticks life cycle. To fill this gap, a record was made of its development under laboratory conditions. All the procedures were controlled in a BOD chamber set at 27±1 °C and 80±10% relative humidity and scotophase. The parasitic stages were raised on rabbits (Oryctolagus cuniculus Linnaeus, 1758), from which more than 50% of larvae and nymphs were recovered, although only a small portion performed ecdysis. The adults did not fixed on the rabbits, which suggests that the experimental conditions were unsuitable for the requirements of this species. The data obtained here indicate that A. nodosum is highly dependent on its host and environment whereas under laboratory conditions and host chosen for the study was not obtained satisfactory results and new studies with different hosts and new environmental conditions should be elaborated.

New record, host and localities of bat mite of genus Chirnyssoides (Acari, Sarcoptiformes, Sarcoptidae)

Chirnyssoides parasitizes the anterior and posterior edges of bat wing membranes. Possibly due to a lack of studies, its distribution is believed to be restricted to a few countries of Central and South America, but its actual range is probably wider. The purpose of this paper is to report the presence of Chirnyssoides amazonae on the bat Carollia perspicillata in the state of Rio de Janeiro, Brazil, and to present a checklist of hosts and localities for Chirnyssoides. Eleven females and 22 egg clusters of C. amazonae were collected from 11 individuals of C. perspicillata captured in Tinguá Biological Reserve using mist nets. Our search of the literature came up with 69 records of Chirnyssoides. There are reports of Chirnyssoides caparti, Chirnyssoides amazonae, Chirnyssoides brasiliensis and Chirnyssoides phyllostomus in Brazil. This paper reports the first record of Chirnyssoides amazonae in the state of Rio de Janeiro and the second in Brazil, indicating that their known distribution extends to the south. There are records of C. amazonae and C. surinamensis parasitizing C. perspicillata, but this is the first record of C. amazonae on C. perspicillata in Brazil.