Did you know there are more species of day-flying moth in Britain than there are butterflies? Many of these moths are as brightly coloured (or more so) as their popular cousins; good examples are the Tiger moths, the Burnets, the clearwings and the Cinnabar. It is this last species I want to focus on in this post.
The Cinnabar has a simple beauty; with a solid black background colour to the body and wings which is highlighted with strong, simple crimson marks that make a thick line and two dots on the forewings and cover all but the borders of the hindwings. As a child I would have great fun searching for the equally striking larvae on country walks, these were always found clustered on the stems of Ragwort, their black and yellow stripes matching the yellow of the flowers. This is probably the first moth species that I was able to identify as a child, it is quite unique in its pattern and being easy to find in the day helped too, it is a species which is ideal for getting kids into insects, moths and the wider natural world.
- The name ‘Cinnabar’ comes from the red marks on the wings which are a similar tint to the namesake mineral ore (which is perhaps more brick coloured). The Latin name ‘Tyria jacobaeae’ is a reference to the Common Ragwort, the main foodplant, which is ‘Jacobaea vulgaris’.
- The Cinnabar is superficially similar to the Burnet moths, with a bold black and red colouring, but is actually more closely related to the colourful Tiger and Ermine moths.
- Its flight season lasts from mid-May to early August, with larvae and adults visible at the same time. It overwinters as a pupae underground.
- Variation is rare but there are a few colour morphs including an all-red form, an all-black form and one where the red markings are coloured yellow.
- This moth has been introduced into Australasia and North America in order to control invasive Ragwort, which is a poisonous plant dangerous to livestock, which it apparently does quite efficiently.
- The larvae and adult moth are so brightly coloured as a warning to predators that they are toxic to eat, the moth absorbs alkaloids from Ragwort as it eats it and birds seem to leave it alone (except the Cuckoo).
- The females can lay up to 300 eggs, often on the same plant, this crowding can lead to large losses of larvae as they starve when the plant is all consumed, this can lead to cannibalism.