Spanolepis selloanae as a potential biological control agent for Cortaderia selloana
A newly described gall midge Spanolepis selloanae Gagné (Diptera, Cecidomyiidae) was discovered in a large population of Cortaderia selloana (Poaceae – EPPO List of Invasive Alien Plants) in the outskirts of the city of A Coruña in Galicia, North-West Iberian Peninsula (Spain). The gall midge is morphologically quite distinctive and can easily be separated from other gall midge species found on grasses. In 2016, larvae and adults of S. selloanae were found feeding on the developing ovaries and their feeding behaviour acted to limit the number of seeds at the time of dispersal. As C. selloana reproduces and spreads by wind dispersed seed it could be an interesting biocontrol agent. S. selloanae was only found on female plants, and plants that were infected with the gall midge had 25 % less seed production. Viability of the remaining seeds was not affected by the presence of S. selloanae. This report is the first known report of a natural enemy feeding on C. selloana in Spain.
Sources
Fagúndez J, Gagné RJ, Vila M (2020) A new gall midge species (Diptera, Cecidomyiidae) as a potential candidate for biological control of the invasive plant Cortaderia selloana (Poaceae). Phytoparasitica 49, 229-241.