Take shelter

QMARY BAINES writes: I apologise for the quality of the photograph, which was taken with a cellphone by a friend living in Windhoek. She found this pupa case, created from bougainvillea flowers and leaves, on the frame of a seldom-opened window. Can you tell us what has created this marvel of a home?

AEntomologist DUNCAN MACFADYEN says: This is a fascinating photo. It’s the work of a moth within the group Pyralidae – their larvae create such shelters. The Pyralidae, commonly called snout moths, are one of the largest families in the Lepidoptera. The size of the shelter depends on the amount of material available, and the size of the larva. Larva size varies considerably, depending on the availability of food. Looks like this one had more than enough to eat!