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Objective: To investigate the seasonal variation of sand flies regarding their occurrences and densities., Methods: The study was conducted in the Aguapeí river floodplain in the state of São Paulo, southeastern Brazil. Sand flies were monthly captured with automatic light traps set up between 18:00 and 7:00 hours, over a period of one year (2004-2005), at two sites: veranda of a domicile and in a forest on the banks of Aguapeí River. The Williams' average was used for estimating the seasonal variation and the Chi-square test for comparison., Results: A total of 35,995 specimens were captured: five Brumptomyia avellari, one Psathyromyia (Xiphomyia) hermanlenti and the rest Nyssomyia neivai, which had the highest frequency during the winter. Ps. hermanlenti is first recorded in state of São Paulo., Conclusions: The high density of Nyssomyia neivai, a suspected vector of cutaneous leishmaniasis, points out to the risk of transmission of this disease in this setting, especially during drier periods of the year.

The aim of the study was to identify among the phlebotomine fauna potential leishmaniasis vectors. The study was carried out in Corumbá county, State of Mato Grosso do Sul, Mid-West Brazil (18 degrees 59' S, 56 degrees 39' W). Sand fly captures were undertaken fortnightly with automatic light traps at 11 sites in forested environments and anthropic areas from April 2001 to July 2003. A total of only 41 specimens were captured. Thirty-one percent of the specimens were captured in forests and 68.3% in anthropic areas. The predominance of non-anthropophilic groups and the low density of N. whitmani, a known cutaneous leishmaniasis vector, does not seem to indicate any actual risk of the transmission of this disease in the study area.

Objective: To identify the sandfly fauna and some aspects of their behavior in forest and anthropic environments., Methods: Sandfly captures were undertaken in farm (23 degrees 6' S; 50 degrees 22' W), in Southern Brazil. Falcão light traps were set in forest, domicile and domestic animal shelters and mosquitoes were collected monthly, between 17h and 7h, from March 1997 to February 1998., Results: A total of 3,655 specimens representing 13 species were captured. Nyssomyia whitmani and Nyssomyia neivai were the predominant species, with a total of 2,977 specimens (81.0%). Of these two species, a total of 2,552 (85.7%) specimens were captured in intradomiciliary and peridomiciliary environments, 2,332 (91.3%) of them in a pigsty. These two species predominated between 20h-21h when 90.4% of the specimens were captured., Conclusions: Five sandfly species, N. whitmani, N. neivai, Migonemyia migonei, Pintomyia pessoai and Pintomyia fischeri, potential vectors of cutaneous leishmaniasis, were captured. The importance of the two former species is emphasized, since both presented similar behavior in regard to seasonal period, hourly frequency and predominance in the anthropic environment. Besides, N. whitmani was the most predominant species.

A serological survey was made in 973 stray dogs caught near green areas in S. Paulo county by the indirect immunofluorescence test. No positive serum was found, however autochthonous human cases of ACL that occurred in the county show the circulation of the parasite in the environment. This fact, associated with the existence of the vectors and the apparent absence of infected dogs in the areas studied, suggest that stray dog plays an insignificant role in the spread of the parasite. The cycle of the parasite in São Paulo county has been maintained by wild animals, hence the dog would be an accidental host just as humans.

Introduction: Lutzomyia intermedia s. s. and L. neivai, usually considered as belonging to just one species, constitute a complex of species. The measurements of several anatomical structures of specimens of both groups, from Brazil, Paraguay, Argentina and Bolivia were analysed., Method: Thirty-nine structures were measured in specimens of both sexes, using a graduated ocular, analysing comparisons by analyses of variance (ANOVA)., Results: A significant deviation in the proportions of females and males showing each palpal formula and the influence of the region of origin of the flies were verified. Labrum and maxilary palps were longer in females and Antennomere III was longer of males. Several significant differences in the measurements of wings were noted, most of them greater in females. The proportion of spermathecae with simple heads was significantly greater in L. neivai than in L. intermedia. Significant differences in the length of genital pump and filaments between the species were also noted., Discussion: The variation in the palpal formulae in both sexes show the risk of the use of this formula for the association between specimens of the two sexes. The differences in the lengths of palps and labrum between the sexes could be related to female blood feeding. The possible biological significance of the sexual differential relation length/width of wings is commented on. The different proportions of females of the two species with each spermathecae head shape may help in identification. The differences in the lengths of genital pumps and filaments and the relation between them could help in the identification of males, which is still difficult.

Introduction: In the Americas, Lutzomyia longipalpis has been incriminated as the vector of visceral leishmaniasis in almost all the areas in which this disease has been reported. The notification of human cases of visceral leishmaniasis and the presence of dogs with an appearance suggestive of the disease in the country of Corumbá, Mato Grosso do Sul State, Brazil, led us to undertake an entomological investigation in this area, for the purpose of identifying the phlebotomine vector., Material and Method: The county of Corumbá is located in the Pantanal region and its urban area is situated at 18 degrees 59' 44" South and 57 degrees 39' 16" West. The research project was carried out in peri and intradomiciliary environments, in three urban districts, one of which was central and the other two on the outskirts, and in a cave situated outside the urban perimeter. Most of the captures were made weekly with light automatic traps, in the period from February 1984 to December 1986. Meteorological data for this period were obtained from the city's meteorological station and those for the period from 1925 to 1982 from the literature., Results: The urban phlebotomine fauna consisted of eight species and was similar to that of the cave, except that in the latter the species were more abundant. Lutzomyia cruzi was predominant in the peri and intradomiciliary environments. Its prevalence in the central district was of 90.3% and lower in the outskirts. Lu. forattinii presented considerable prevalence (39.0%) in one of the outlying districts too. In the cave, Lu. corumbaensis was the predominant species, followed by Lu. sordellii, Lu. forattinii, Lu. peresi and Lu. cruzi. The impact of the climatic condition and the action of insecticides in the urban area on the frequency of the species, as well as the use of the cave as a breeding ground by the phlebotomines, in view of the changes in the sex rate, are commented. Data on anthropophily and captures of Lu. forattinii using dog bait have been added., Conclusion: The predominance of Lu. cruzi in the urban area; the great prevalence of Lu. forattinii in most of the outlying areas studied and the anthropophily of this latter species, as well as the strong affinity of these species with Lu. longipalpis, the main vector of visceral leishmaniais in other areas of the Americas, suggest the participation of both in the transmission of the disease in Corumbá.

Studies of the phlebotomine sandflies on the Boa Sorte farm, Corguinho country, State of Mato Grosso do Sul, Central-West region of Brazil, were carried out, with the object of identifying local fauna and a cutaneous leishmaniasis vector. At the beginning of the studies, several types of primitive vegetation covering: gallery forest, forest slopes and the cerrados: s. str. and tropical xeromorphic semideciduous broadleaf forest, locally denominated "croa", existed. Four months after the beginning of the studies, a fire destroyed a significant part of the cerrados. Captures were made during the interval from July/91 to June/93, with a CDC trap, weekly, at 10 ecotopes: in the soil of forest slopes; in the soil and canopy of cerrado s. str., "croa" and gallery forest; in the peridomicile, in hen house and pigpen and in a storage shed. A Shannon's trap was used, monthly, from 18:00-24:00 hours, in the gallery forest and "croa". Human bait was used, monthly, for 24 hours, from June/91 to September/92. An investigation into natural infection in female phlebotomines was made through the dissection of specimens captured in the Shannon's trap and on human bait. The captures with CDC totalled in 2,281 specimens of 26 species: 2 of Brumptomyia and 24 of Lutzomyia. The "croa" was the environment that contributed with the greatest number of specimens and presented the largest diversity, together with the forest slope. L, withmani was the most abundant species captured with CDC, in all the ecotopes (Standardized abundance index = 0.991). However, in the storage shed its frequency was the lowest. This species presented a prevalence of 96.0% in the Shannon's trap and on human bait (3,265 and 516 specimens, respectively). It was the most frequent in the cold and dry periods. It presented almost exclusively nocturnal activity, with its peak at 18:00-19:00 hours and an infection rate by flagellates of 0.16% (613 females dissected). On the basis of its behavior, this species was incriminated as the probable vector of the cutaneous leishmaniasis in the area, which had extradomicilary transmission. L. lenti, the second most abundant species, is not anthropophilic. The phlebotomine fauna is presented by environment.

Description of Lutzomyia robusta, n. sp. (Diptera, Psychodidae, Phlebotominae) from interandean areas of Peru and Equador. Lutzomyia robusta, n. sp., probable vector of human bartonellosis and cutaneous leishmaniasis, is described and illustrated. This species presents strong affinity with L. serrana (Damasceno & Arouck, 1949) but they can be distinguished by variance analysis of four male characteristics and only one female characteristic. In the variance analysis, populations of L. serrana, of Amazonian areas of Brazil, Peru and Bolivia, the coast of Equador and other areas of Brazil were studied. The synonymy of Lutzomyia guayasi (Rodriguez) and L. serrana was corroborated.

Five species of phlebotomine sandflies were caught on the Southern part of the coast of S. Paulo, Brazil. CDC-light and Shannon traps were used, as well as human-bait, during two investigations into Culicidae mosquitoes. Lutzomyia intermedia and L. flaviscutellata were found among those sandflies. The localities investigated were swampy environments and scant human cases of cutaneous leishmaniasis have been notified there. Both situations suggest the autochthonous nature of the human cases registered there.

A total of 5,038 specimens, belonging to nineteen species, were obtained during the three consecutive years of phlebotomine catches in forest and peridomiciliary environments of the Itapoan farm. Proportionally, the CDC light trap contributed with 92.2% in the forest and 0.7% in the peridomicile sites while the human bait corresponded to 7.0% in the forest. Generally speaking the outcome of the technique utilized was rather low or presented reduced geometrical averages. The most common species in the area was P. ayrozai, almost always predominant; however, the results with human bait prevent one's ascribing a high degree of anthropophilic properties to it. The implication of the reduced presence of L. intermedia, L. migonei and L. fischeri, even with human bait, is that the conditions for the transmission of the disease to man in the forest environment are inexistent. Consequently, this could indicate that the vectorial function would be performed by a population which has survived the period of devastation. For this reason a new epidemiological pattern, connected with a focus, of L.b. braziliensis seems to exist in Brazil.