Beware the grey cocoons on the wall – the larvae in them can sting

This is a cocoon of the plaster bagworm larvae, which is typically found on the walls of humid areas in a home. — Wikimedia Commons

Plaster bagworms may be sound unfamiliar to most people, compared to other insects such as mosquitoes, bees and wasps, even though these peculiar pests can be seen strewn over their house walls.

Known scientifically as Phereoeca uterella, this moth species is greyish, flat and roughly half an inch long.