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The cinnabar moth (scientific name Tyria jacobaeae) is a moth in the family Eribidae and the genus Tyria. The moth is named for the red mineral cinnabar, whose pigment it bears on its wings that is similar to the ore of the metal Mercury. This pigment gives its name to this species of moth – “Cinnabar”. It is often mistaken for the similar Burnet moths, but cinnabars have broader wings and red bars instead of just pinky-red spots.

Cinnabar Moth Identification

Cinnabar moth, Tyria jacobaeae, resting in a meadow
Cinnabar moth resting in a meadow

The Tyria jacobaeae are one of the most striking yet gentle-looking moths that can be found. The cinnabar moth is a large, slate-black insect that is marked with red blotches across the wings. It has two red spots and two pinky-red stripes (or red bars) on the rounded forewings.

The underside of the wings has creamy white patches, but these may vary from pale cream to deep reddish-brown to aid in camouflage against its surroundings.

Males are generally lighter than females and have salmon-coloured hindwings with narrow dark borders. Females have dark hindwings with yellowish-orange borders bordered by black veins. The cinnabar moth is about 2.5 centimetres long with a wingspan of 34-46mm.

Cinnabar Caterpillar Identification

A pretty Cinnabar moth Caterpillar (Tyria jacobaeae)

Cinnabar caterpillars are another striking feature of this wonderful moth. These black and yellow caterpillars are as beautiful as the black and red moths.

Cinnabar larvae have black bodies with yellow stripes. Although the larvae’s bright colours warn predators, sometimes it isn’t enough. Therefore, it is covered in short forked spines or small spikes that are red or orange in colour. These spikes may be branched and up to 1 cm long at the end of each segment.

Cinnabar Moth Life Cycle

The females lay their eggs in groups of 30 to 80 on the underside of leaves of the host plant during spring or summer in clusters that are well camouflaged. After they hatch, the cinnabar caterpillars will feed in groups until Autumn, when they will live alone. During this time, they change colour from yellow to red and then hibernate for the winter in underground chambers where cinnabar moths start life, emerging the following spring as adults.

What Do Cinnabar Caterpillars Eat?

Cinnabar Moth (Tyria jacobaeae), caterpillars, feeding on Ragwort
Cinnabar caterpillars feeding on ragwort in Wales, United Kingdom

Cinnabar caterpillars spend plenty of time feeding. They love to eat the ragwort plant (Senecio jacobaea) and groundsel (Senecio vulgaris). These yellow and black caterpillars feed on these plants by rasping the foliage to extract food. They have been introduced to parts of Australia to help with biological control, as the growth of common ragwort plants and groundsel prevent other plants from growing.

Cinnabar larvae are known to display cannibalistic behaviour and often eat other cinnabar caterpillars.

What Do Cinnabar Moths Eat?

Flower cluster of a common ragwort or stinking willie
Common ragwort

The diet of the cinnabar moth consists of insects and pollen from ragwort plants and groundsel.

Cinnabar Moth Behavior

These large, intricately patterned moths are very active during the day, flying and clinging to foliage with their long legs and antennae. They prefer open-canopied forest types with high humidity and a mixture of deciduous and evergreen trees. They are non-migratory and are often found near cities and towns. They often stay close to water, as well as the flowers of their host plant.

Common Predators

The striking yellow and black stripes of cinnabar larvae are a common sight on ragwort plants, so they are easily found by hungry hunters. The bright colours warn predators, yet still, the cinnabar larvae and moth are preyed upon by various insects such as dragonflies, wasps, flies, and beetles. They are also eaten by birds, reptiles, bats and even humans.

Are Cinnabar Moths Dangerous?

This red and black winged moth is a cinnabar moth
Photograph captured in a garden in Staffordshire, UK in June

Adult moths are not dangerous to humans, but this enormous moth can often be found near houses and other locations where humans are. This can cause some alarm for people who do not know what it is. In some countries in Europe, where the species is more common, they have been associated with witchcraft and black magic.

The larvae of the cinnabar moth are poisonous to many animals due to their colourful skin and sharp spines, which may cause allergic reactions in some dogs and cats. However, birds usually take care of these caterpillars without any problems.

Are Cinnabar Moths Rare?

The cinnabar moth is not as rare as previously thought. They have been introduced to parts of Australia and some of the southern states of America, where they have interbred with other species and form a mixture referred to as “Tyria.”

Sources and References

  1. Cinnabar Moth – Tyria Jacobaea – first-nature.com
  2. The Cinnabar Moth and Caterpillar – wildlifeinsight.com

2 thoughts on “Cinnabar Moth (Tyria Jacobaeae)”

  1. Fantastic answers to my questions, which will be passed on to my granddaughter as she found the caterpillars. Many thanks.

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