The flower flies and the unknown diversity of Drosophilidae (Diptera): a biodiversity inventory in the Brazilian fauna

Abstract

Diptera is a megadiverse order, reaching its peak of diversity in Neotropics, although our knowledge of dipteran fauna from this region is grossly lacking. This applies even to the most studied families, such as Drosophilidae. Despite its prom-inence, most aspects of the biology of these insects are still poorly understood, especially those linked to natural communities. Field studies on drosophilids are highly biased towards fruit-breeding species. Flower-breeding drosophilids, however, are worldwide distributed, especially in tropical regions, although being mostly neglected. The present paper shows the results of a biodiversity inventory of flower-breeding drosophilids carried out in several localities in Brazil, based on samples of 125 plant species, from 47 families. Drosophilids were found in flowers of 56 plant species, from 18 families. The fauna discovered turned out to be mostly unknown, comprising 28 species, with 12 of them (> 40%) still undescribed. Not taking into account oppor-tunistic species, two-thirds of the flower-exclusive diversity was undescribed. The Drosophila bromeliae species group was the most representative taxon, with eight species (six undescribed), including four polyphagous and four Solanum-specialized species. This specialization on Solanum is reported for the first time for Drosophilidae. Other taxa of restricted flower-breeding drosophilids were the Drosophila lutzii species group and two species of the genus Zygothrica Wiedemann. Some specimens of the genera Cladochaeta Coquillett, Rhinoleucophenga Hendel and Scaptomyza Hardy were found, but their relations to flowers are unclear. Additionally, ten species of broad niche were found using flowers opportunistically. Localities and host plants were recorded for all species collected.