An immigrant species, which sometimes occurs in large numbers. A large influx occurred in the summer of 2000, when moths were observed in parks and gardens all over Britain.
The larvae feed on bedstraw (Galium), and some of these may hatch and give rise to autumn adults in an influx year.
Resembles a hummingbird in flight. Orange-brown hindwing and underside are evident in flight as it flits rapidly between plants, hovering to feed at tubular flowers of such species as Viper’s bugloss, Red Valerian, Phlox, Jasmine, Buddleias, Petunia and Lilac.
Active by day, mainly in sunshine, but sometimes in overcast weather, rain, at dusk or after dark.