Tyria jacobaeae

Tyria jacobaeae (Linnaeus, 1758)
Cinnabar Moth
(one synonym : Callimorpha senecionis Godart, 1822)
ARCTIINI, ARCTIINAE, EREBIDAE, NOCTUOIDEA

Don Herbison-Evans
(donherbisonevans@yahoo.com)
and
Stella Crossley

Tyria jacobaeae larva
(Photo: Don Herbison-Evans)

The first instars of these Caterpillars are yellow with a black head. Later, they become more brightly coloured with black and yellow bands. There are two long white bristles near the head and the tail.

(Photo: Don Herbison-Evans)

When they are worried, the caterpillars curl into a tight circle. The caterpillars feed initially on the leaves of plants in ASTERACEAE, but as their foodplant matures, they move onto the flowers. The species has been introduced deliberately from Europe into Australia and other countries several times since 1930, especially to control the weed:

Ragwort (Jacobaea vulgaris, ASTERACEAE).

Ragwort contains many different alkaloids, making it poisonous to Horses and Cattle. The caterpillar has ostentatious colours warning that it too is poisonous, retaining in its body some of the alkaloids from the Ragwort. Curiously our attempts to rear these caterpillars to the adult moths have always been thwarted by the caterpillars being infected with parasitic wasps. Apparently, the poisons may deter some predators, but not wasps.

When fully grown, the caterpillars go walkabout, and pupate some distance from the foodplant in a loose flimsy cocoon in a dried curled leaf, or a crevice, or some other sheltered spot.

(Photo: courtesy of CBG Photography Group, Centre for Biodiversity Genomics, University of Guelph)

The adult moth is shiny black with a red line along the costa and two red spots on each forewing, and has red hindwings. It has a wingspan of about 3 cms.

(Picture: by Leroy Simon, Visuals Unlimited,
courtesy of Nature Conservancy)

The moths appear to be reluctant fliers, just moving on a metre or so when disturbed. Components of the pheromones have been determined.

Eggs are spherical and yellow when first laid, but become darker later. They are laid in groups of about 50, usually on the underside of leaves of a foodplant.

The species is endemic to Europe, occurring in

Great Britain,

Nederlands, and

Turkey,

and it has been introduced elsewhere into

Canada,

New Zealand,

United States,

and also into Australia, and now may occur in

Queensland,

New South Wales,

Victoria, and