Geographic Expansion of an Invasive Fly: First Record of Zaprionus tuberculatus (Diptera: Drosophilidae) in the Americas

Due to the increase in global transport in recent decades, species that flourish in human-altered environments are widening their geographical distribution. Consequently, endemic species are either declining or going to extinction. Here, we report the first occurrence of the Afrotropical fly Zaprionus tuberculatus Malloch in the Americas. This species has been recognized as invasive by the Invasive Species Compendium, and we argue that it will probably impact drosophilid communities. Our study was conducted on the natural and urban environments of the Brazilian Savanna, a biodiversity hotspot where drosophilid communities have been monitored since 1999. Z. tuberculatus was first collected in January 2020, at low abundances, in urban parks located in Brasilia. In December 2020, we recorded it in a preserved area approximately 200 km away from the urban parks. From January to March 2021, we found the species in seven urban parks in Brasilia and three natural reserves (conservation units) located around the city. The species' relative abundance increased from 0.9% in 2020 (n = 11,244 drosophilids) to 17% in 2021 (n = 6,002 drosophilids). This is a rare opportunity to monitor a recent invasion event in a well-studied area. Based on the impact of Z. indianus Gupta, which invaded the Brazilian Savanna in 1999 and remained the dominant species during the rainy seasons, we fear that this new arrival will reduce the diversity of drosophilids in the Neotropics.

Automated summary

The increase in global transport has led to the expansion of species adapted to human-altered environments, causing a decline or extinction of endemic species. This study reports the first occurrence of the Afrotropical fly Zaprionus tuberculatus Malloch in the Americas, with potential impacts on drosophilid communities. The invasive species was found in urban parks and natural reserves in the Brazilian Savanna, indicating a rise in its relative abundance and raising concerns about the diversity of drosophilids in the Neotropics.