Cinnabar moth
Encyclopedia
The Cinnabar moth is a brightly coloured arctiid
moth
, found in Europe and western and central Asia. It has been introduced into New Zealand
, Australia
and North America
to control poisonous ragwort
, which its larvae feed on. The moth is named after the red mineral cinnabar
because of the red patches on its predominantly black wings. Cinnabar moths are about 20mm long and have a wingspan of 32–42 mm (1.3-1.7 in).
Cinnabar moths are day-flying insects. Like many other brightly coloured moths, it is unpalatable; The larvae use members of the genus Senecio
as foodplants. Many members of the genus have been recorded as foodplants but for long term population success the presence of the larger species such as ragwort is needed. Smaller plant species such as groundsel are sometimes used but since the species lays its eggs in large batches survival tends to be reduced. The larvae absorb bitter tasting alkaloid
substances from the foodplants, and assimilate them, becoming unpalatable themselves. The bright colours of both the larvae and the moths act as a warning sign so that they are seldom eaten by predators.
Like several other Arctiidae moth larvae, the Cinnabar caterpillars can turn cannibalistic. This can be due to lack of food, but they can eat other Cinnabar larvae for no apparent reason. Females lay up to 300 eggs, usually in clusters of 30 to 60. Initially the larvae are pale yellow but later larval stages develop the jet black and orange/yellow striped colouring. They feed ravenously and can grow up to 30mm. Cinnabar caterpillars are voracious eaters and large populations can strip entire patches of ragwort clean, a result of their low predation.
Often very few survive to the pupa stage, mainly due to them completely consuming the food source before reaching maturity; this could be a possible explanation for their tendency to engage in seemingly random cannibalistic behaviour, as many will die from starvation.
The moth has proven to be particularly successful as a biocontrol agent for ragwort when used in conjunction with the ragwort flea beetle
in the western United States.
Image:Tyria_jacobaeae_caterpillar.jpg|Cinnabar moth caterpillar on ragwort
Image:Tyria jacobaeae pupa.jpg|Pupa
Image:Tyria jacobaeae (Edkins).jpg|Adult in resting posture
Image:Tyria jacobaeae-02 (xndr).jpg|Adult showing hindwings
File:Tyria jacobaeae mating.jpg|Mating
Image:Britishentomologyvolume5Plate499.jpg|Illustration from John Curtis's British Entomology Volume 5
Arctiidae
Arctiidae is a large and diverse family of moths with around 11,000 species found all over the world, including 6,000 neotropical species. This family includes the groups commonly known as tiger moths , which usually have bright colours, footmen , lichen moths and wasp moths...
moth
Moth
A moth is an insect closely related to the butterfly, both being of the order Lepidoptera. Moths form the majority of this order; there are thought to be 150,000 to 250,000 different species of moth , with thousands of species yet to be described...
, found in Europe and western and central Asia. It has been introduced into New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
and North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
to control poisonous ragwort
Senecio
Senecio is a genus of the daisy family that includes ragworts and groundsels. The flower heads are normally rayed, completely yellow, and the heads are borne in branched clusters...
, which its larvae feed on. The moth is named after the red mineral cinnabar
Cinnabar
Cinnabar or cinnabarite , is the common ore of mercury.-Word origin:The name comes from κινναβαρι , a Greek word most likely applied by Theophrastus to several distinct substances...
because of the red patches on its predominantly black wings. Cinnabar moths are about 20mm long and have a wingspan of 32–42 mm (1.3-1.7 in).
Cinnabar moths are day-flying insects. Like many other brightly coloured moths, it is unpalatable; The larvae use members of the genus Senecio
Senecio
Senecio is a genus of the daisy family that includes ragworts and groundsels. The flower heads are normally rayed, completely yellow, and the heads are borne in branched clusters...
as foodplants. Many members of the genus have been recorded as foodplants but for long term population success the presence of the larger species such as ragwort is needed. Smaller plant species such as groundsel are sometimes used but since the species lays its eggs in large batches survival tends to be reduced. The larvae absorb bitter tasting alkaloid
Alkaloid
Alkaloids are a group of naturally occurring chemical compounds that contain mostly basic nitrogen atoms. This group also includes some related compounds with neutral and even weakly acidic properties. Also some synthetic compounds of similar structure are attributed to alkaloids...
substances from the foodplants, and assimilate them, becoming unpalatable themselves. The bright colours of both the larvae and the moths act as a warning sign so that they are seldom eaten by predators.
Like several other Arctiidae moth larvae, the Cinnabar caterpillars can turn cannibalistic. This can be due to lack of food, but they can eat other Cinnabar larvae for no apparent reason. Females lay up to 300 eggs, usually in clusters of 30 to 60. Initially the larvae are pale yellow but later larval stages develop the jet black and orange/yellow striped colouring. They feed ravenously and can grow up to 30mm. Cinnabar caterpillars are voracious eaters and large populations can strip entire patches of ragwort clean, a result of their low predation.
Often very few survive to the pupa stage, mainly due to them completely consuming the food source before reaching maturity; this could be a possible explanation for their tendency to engage in seemingly random cannibalistic behaviour, as many will die from starvation.
The moth has proven to be particularly successful as a biocontrol agent for ragwort when used in conjunction with the ragwort flea beetle
Longitarsus jacobaeae
Longitarsus jacobaeae is a species of flea beetle known as the tansy ragwort flea beetle. It is used as an agent of biological pest control against the noxious weed known as ragwort ....
in the western United States.
Image:Tyria_jacobaeae_caterpillar.jpg|Cinnabar moth caterpillar on ragwort
Image:Tyria jacobaeae pupa.jpg|Pupa
Image:Tyria jacobaeae (Edkins).jpg|Adult in resting posture
Image:Tyria jacobaeae-02 (xndr).jpg|Adult showing hindwings
File:Tyria jacobaeae mating.jpg|Mating
Image:Britishentomologyvolume5Plate499.jpg|Illustration from John Curtis's British Entomology Volume 5