Discovery: Jurassic insect mimicked Ginkgo leaf
Preserved in fossil sediments dating from the late Middle Jurassic, the insect, newly named Juracimbrophlebia ginkgofolia, was discovered in 165 million-year-old deposits, as was the extinct ginkgo-like tree, Yimaia capituliformis, the mimicked plant.
Hanging down by its long forelegs from the bottom of a leaf petiole, the four long wings and body of this insect would have perfectly mimicked the hanging lobes of a single ginkgo-like leaf.
The researchers suggest the hangingfly may have evolved this mimicry to hide from predators, such as other insects, pterosaurs and small, tree-living dinosaurs and mammals, since its relatively large body and weak legs and wings would have made it easy prey. The insect also may have used mimicry to help ambush prey.
It will make the newly found Juracimbrophlebia ginkgofolia the first of its kind by tens of millions of years, as well as the first to use leaves, rather than flowers, to hide. It will also mark the first recorded example of animal and plant evolving to work together in such a way, with the tree providing cover for hangingflies, who in turn offer pest control by devouring potentially dangerous insects before they can damage the tree. In this way the insect benefited from a reciprocal relationship with the tree, a relationship that the fossils indicate lasted about 1 million years.
Phys.org + PNAS
Dong Ren et al., Jurassic mimicry between a hangingfly and a Ginkgo from China, 2012 PNAS,
Pictures:- Art by Wang Chen, from Wang et al., 2012.- Juracimbrophlebia ginkgofolia from PNAS 2012.