Lacewing. Coloured Scanning Electron Micrograph (SEM) of a green or common lacewing, Chrysopa sp. Lacewings are distinguished by their delicate, net-veined wings. They prey on smaller insects such as aphids and are most active at twilight, when they often congregate around lit windows. Some lacewings, known as "stink flies", release a putrid odour when touched. Magnification: x16 when printed 10 centimetres wide.