Field Notes: Leaf Miners (Patreon)

For our next episode of Deep Look, producer Gabriela Quirós is putting the spotlight on the larvae of leaf-mining flies called Scaptomyza, which are cousins of fruit flies. You’ll see how the larvae tunnel through the spongy layer of leaves, feeding as they go. Scaptomyza leaf miners live in plants like arugula, kale and wild mustard.

These bitter-tasting greens, which produce toxic chemicals that keep other insects away, also give them a strong flavor that some people find delicious.

In this photo, the papery outside layer of the leaf, called the epidermis, has been peeled back to reveal a Scaptomyza larva.

UC Berkeley doctoral candidate Jessica Aguilar studies Scaptomyza. She keeps the plants and flies inside white mesh boxes.

Aguilar’s flies live on tiny plants related to cabbage and mustard called Arabidopsis. The fly larvae like eating through their soft leaves.

Here you can see the white blotches and lines –– the mines –– created by a Scaptomyza larva or larvae as they fed inside this wild mustard leaf.

This episode premieres next Tuesday, April 6, but Patreon supporters will get a sneak peek this Friday!

Deep Look cinematographer Josh Cassidy filmed with doctoral candidate Jessica Aguilar in a field of wild mustard at UC Berkeley.

Photo credit for all photos: Josh Cassidy/KQED