Drosophilidae and 48 other dipterous families from localities in New South Wales and Victoria, Australia

On high-temperature summer days, with strong wind and low humidity, species of <i>Drosophila</i> and related genera, and of Diptera generally, are more frequently found in places that are darker (suggesting negative phototropism), lower down (suggesting positive geotropism) and damper or where desiccation stress is minimal (suggesting positive hydrotropism). At three such shaded, humid, gully sites, two in the NSW North Coast bioregion (IBRA NNC17, NNC13) and three in the South Eastern Highlands bioregion (IBRA SEH01) drosophilid flies were surveyed for short periods by net-sweeping during hot summer months of 2018–2019. All other Diptera were retained and sorted to family. Very little is known of dipterous diversity at the family level at any one locality in Australia. This is because few studies have immediate access to expert taxonomists who can provide determinations right across the order with very high confidence. Equally unusual is for a single survey to focus on all families in one large order (Diptera) and, at the same time, on all species in one of those families (Drosophilidae), as is the result presented here. Surveys ceased at each bioregion after about 2500 specimens had been collected (Table 4).