Food thieves

A trap, but not for me: fly larva glides across tentacles of Drosera graomogolensis

Paulo Gonella/USP A trap, but not for me: fly larva glides across tentacles of Drosera graomogolensisPaulo Gonella/USP

With their tiny red tentacles covered in sticky goo, the carnivorous plants of the genus Drosera hunt small insects. Prey that land on their flowers get stuck and end up digested. Some invertebrates, however, are able to evade the lethal trap and steal the plant’s food instead of becoming dinner themselves, in a feeding strategy known as kleptoparasitism. One such example are the larvae of the flower fly Toxomerus basalis, whose behavior was described by a research group led by German botanist Andreas Fleischmann from the Botanical Collection of Munich. Using scanning electron microscopy, the team analyzed the morphology of larvae found in Drosera plants on the Pico do Padre Ângelo, a mountain in the state of Minas Gerais, and conducted genetic analyses to confirm their identity (PLOS One, May 4, 2016). The researchers described and confirmed an observation made 20 years earlier by biologist Fernando Rivadavia, from the US-based biotechnology company Illumina, who was then an undergraduate student with a passion for carnivorous plants. This is the first report of kleptoparasitic fly larvae being found in plants with adhesive tentacles. The finding suggests that this strategy may be more common than once thought.