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Introduction: The effectiveness of Simuliidae (Diptera, Nematocera) as indicators of stream health was tested in the urbanizing area of Rome, Central Italy., Methods: 108 sampling sites were investigated in the spring to acquire data on environmental variables and black fly species., Results and Discussion: The comparison of sampling and literature data highlighted the disappearance of some species (Simulium reptans, S. vernum, S. liriense), possibly due to water pollution and land use changes. Correspondence analysis confirms altitude as the main factor influencing black fly species' distribution. However, water quality becomes predominant when considering exclusively plain sites: "ornatum" and "equinum" species groups show the greatest tolerance to chemical pollution. The high course of the Aniene river and its tributaries were sampled bimonthly, confirming the spatial-temporal black fly successions previously observed in central Apennines. The results also indicate that S. ornatum may supplant all other species in areas where the rural use is substituted by urban landscape., Conclusion: In conclusion, black flies can be considered good environmental indicators to assess ecological health of both watercourses and surrounding landscapes.

Mass-attack of Simuliidae-Diptera on man and domestic animals should not be considered only as a consequence of quality of running freshwater, but also as an effect of the actual state of the surrounding area. The territory, in fact, impacts the qualitative properties of a water body and can trigger adverse phenomena, especially so when modified by significant anthropic activities. In different locations the native settings have been replaced by deforestation, intensive farming and zootechnological activities. This paper sets forth the results of some investigations carried out further to a mass attack of Simuliidae-Diptera on man at different sites of the national territory. These results have been re-assessed taking into account the areas of interest and the modifications that they have undergone.

Cephenemya stimulator (Clark) (Diptera Oestridae) is first recorded in Italy parasiting roe deer (Capreolus capreolus). Diagnosis was made by examination of II-III instar larvae (fig. 1-2) from roe deers killed in Trient province. In these last years in the Trentin region, there was an increasing of roe deers number (actually about 20.000); at the same time growed roe deers infestation by C. stimulator (Tab. 1). Females of C. stimulator probably attack young roe-deers lying down on field-pastures near forest (fig. 3). From examination of killed roe-deers (Tab. 2) there is evidence of debilitation status of infested specimens. Location and dislocations of parasitising larvae in the head cavity was that shown in fig. 4 and 5.

A list is given of Sciomyzidae recorded from Italy (Tab. 1). It results from literature and from our collections (species with one asterisk in tab. 1) that there 70 species in Italy. On the other hand some of these (three asterisks in tab 1) are records of old Authors. Some dubious records (in the opinion of Verbeke and Knutson, 1967) are signed with two asterisks in tab 1. Pherbellia annulipes (fig. 1) and Limnia paludicola (fig. 2) seem new records for Italian fauna. The species listed in Tab. 1 have the next types of geographical distribution: central-south-European (30%), European (17,14%), central north-European (15,7%), oloartic (14,2%), west-mediterraneous (8,5%), Eurasiatic (5,7%), borealpine (2,8%). Observations are also reported on preferential habitat of Sciomyzidae collected in some "natural damp places" (see figg. 3-4).

In the urban periphery of Rome, two sub-zones could be distinguished, characterized by uncultivated steppeland and by small shacks with large quantities of domestic refuse, respectively. Rhipicephalus sanguineus appeared to be typical of this second sub-zone. R. sanguineus adults and nymphae were captured in different seasonal periods and were checked for the prevalence of rickettsiae of the Spotted Fever (SF) group. Moreover, larvae from hatched eggs, laid by captured R. sanguineus females, were checked for the transovarial transmission of rickettsiae. Ten lots each of three guinea-pigs, seronegative to rickettsiae of the SF group, were inoculated with R. sanguineus extracts, prepared from adults or larvae. Clinical signs of infection, fever and scrotal reaction, could be observed only in one lot of guinea-pigs inoculated with adult parasites. On the other hand, in 8 out of 10 guinea pig lots, antibodies to the soluble antigens of R. conori and R. slovaca were observed by the complement fixation (CF) test. In the remaining two lots only antibodies to R. slovaca were detected. No antibodies to Coxiella burneti could be demonstrated in the same sera.

The authors present the results of a cytological examination, carried out by the technique developed by Frizzi, of the larvae of a normally susceptible and a dieldrin-selected strain of Anopheles atroparvus, both laboratory-reared. A very high percentage (77.4) of heterozygous inversions was observed in the larvae of the 28th generation of the dieldrin-resistant strain, whereas only 20.8% occurred in the normally susceptible strain, in which the standard chromosomal arrangement predominated (74.2%). These results are similar to those obtained recently by other workers in the case of larvae of the 12th generation of a DDT-selected strain of A. atroparvus (74.8% heterozygous inversions observed).

The development of several DDT-resistant strains of Anopheles atroparvus is described. They were selected by larval treatment only (RL), selection of larval and adult females (RLAF), and selection of adult females and males (RAFM). Their rate of DDT-resistance was measured in the larval and adult states (mainly in the 32nd generation). The results were compared with those of a dieldrin-selected strain (R/dieldrin) and several normal and semi-normal reference strains. In the larval assay DDT-resistance was of the following order: RL>RLAF>RAFM>R/dieldrin. Topical application to adults gave: RLAF>(RL?)>RAFM>R/dieldrin; while adult tarsal contact gave: RAFM>RLAF>RL>R/dieldrin These different orders of resistance are discussed.The strains were subjected to cytological examination by the method of Frizzi. The percentages of heterozygous inversions found were as follows: R/dieldrin, 77.4%; RL, 55.3%; RLAF, 54.0%; RAFM, 24.4%; all normal and semi-normal strains about 12%-21%.The rate of DDT-resistance could not be correlated with the percentages of heterozygous inversions found in the various strains.