African Fig Fly, Zaprionus indianus Gupta. (Photo: Gary J. Steck)
University of Minnesota researchers confirm new invasive fruit fly in Minnesota
MINNEAPOLIS / ST. PAUL (01/30/2014) —Scientists at the University of Minnesota have confirmed a new invasive fruit fly in Minnesota. A single adult female Zaprionus indianus Gupta (Diptera: Drosophilidae), more commonly known as the African Fig Fly, recently was discovered in a fermenting bait trap from late September 2013. The trap was located near Hastings and was being used for annual monitoring of spotted wing Drosophila (SWD), itself a newly invasive Drosophilid. The new fly specimen was officially identified this week by the U.S. Department of Agriculture.
The African Fig Fly is distinguished from other Drosophila species by a pair of distinctive white stripes, outlined in black, running from the antennae to the tip of the thorax. Itis native to tropical Africa, the Middle East, and Eurasia and is a typical pest of fig fruits. The first detection of this species in the United States occurred in 2005 and it has since been found as far north as Michigan and Wisconsin, both reporting their first African Fig Fly in 2012. To date, African Fig Fly populations have remained low in these states.
The African Fig Fly is a generalist feeder and has the potential to affect late season fruits such as grapes, raspberries, blackberries, and strawberries. Unlike female SWD flies, African Fig Fly females have weak ovipositors (structures used to lay eggs) and are primarily known to lay their eggs only in overripe or previously damaged fruit. It is currently unknown whether the African fig fly is capable of overwintering in the harsh winters of Minnesota.
Although scientists currently know very little about the survival and potential impact of this fly in Minnesota, the detection of a single fly indicates that any current Minnesota populations are most likely to be small. "We do not expect the African Fig Fly to pose a significant, immediate threat to Minnesota growers. However, we will continue to monitor for this pest and communicate any future developments to the grower community as further information becomes available," said Anna Kirk, an entomologist at the university whose research uncovered the new specimen.
For information about the new fruit fly, visit the university’s VegEdge web page (http://www.vegedge.umn.edu/). Possible new detections should be sent to the Minnesota Department of Agriculture’s "Arrest the Pest Hotline" by email (firstname.lastname@example.org).