Australian painted lady

Appearance

The Australian painted lady is remarkably similar to the painted lady. It is differentiated by its smaller size, rarely exceeding 2 inches across its wings, and the blue colouration at the centre of the four eyespots on its hindwings.

Its body is dark brown, almost black, all over, except the tips of the antenna which are white. The base of the wings are brown, which turns into a brick-red colouration, broken by bands of black. The tips of the forewing are black with four white dots running from the apex of the wing, and a white bar extending from the leading edge of the forewing. The hindwings have four round eyespots at their base, with a blue centre for at least three.

The underwings are almost identical to the upperwings, except the base of the underwings is brick red rather than brown. The Australian painted lady's colouration allows it to blend in effectively with the ground. Males and females look almost identical. The ovum is translucent green and barrel-shaped with 13 to 15 vertical ribs. Right before hatching, the black head and grey-tinted body appear through the shell.

The larva is grey with pale yellow stripes along each side of its body, yellow dots, and has rows of branched spines covering its body. Its head is typically brown or black, and the caterpillar grows to about 3 cm. The pupa is brown with darker markings, and four pairs of metallic silver or gold dots.

Naming

Some believe that the Australian painted lady should be a subspecies of the painted lady due to the similarity in lifestyle and behaviour. Furthermore, the painted lady is found around the globe, but Australia is the only location in which it varies enough to be considered a separate species.

However, due to the distinct genitalia of the males, and variation in colouration, many others consider the Australian painted lady to be a separate species. During spring, adult butterflies migrate south in large numbers from northern states of Queensland and New South Wales. To find mates, male Australian painted ladies exhibit territorial behaviour, which involves a male perching on vegetation in a sunny spot on a hilltop, waiting for females to fly by.

Despite urbanization and invasive plants altering its habitat, populations of Australian painted ladies have not been significantly impacted by these changes.

Distribution

The Australian painted lady's distribution is restricted to Australia. The closely related ''V. cardui'' is found throughout the rest of the world, so the two species have an allopatric distribution. Within Australia, the Australian painted lady is commonly found throughout southern Australia, below the Tropic of Capricorn. It is uncommon to find this butterfly in Queensland, and it is completely absent from the far north of the country, in the tropical rainforests. Although it is most common in Australia, it has also become common throughout New Zealand following periodic migrations across the sea, from Australia. Since the butterflies do not reproduce or overwinter in New Zealand, they are only considered an established species in Australia. Within its range, it is found in urban areas.

Habitat

Fragmented habitats due to urbanization, as well as disturbances to the environment from humans and introduced species, are harmful to most butterflies. Additionally, threats occur to local vegetation such as recreation, trampling of vegetation, fire regimes, and introduction of plant pathogens, which bring about changes to local plant community. Distribution of butterflies depends heavily on the site characteristics and the density of that species' host plants. Changing plant composition changes the distribution of most butterflies' range, isolating them to pockets where the vegetation is ideal. Because of the variety of host plants used by Australian painted ladies, it has not been significantly affected by these changes. It has been found to use some species of carduine thistles, which are invasive to Australia, as host plants in New South Wales. Australian painted ladies use the plants as hosts during their larval stage, and as food sources. However, they inflict little damage to the plant.

Food

The Australian painted lady typically uses the native Australian everlastings and other daisies as a host and food plant. However, it also feeds on several introduced species, including capeweed, Scotch thistle, and lavender. The adults feed on the nectar of flowers.

Evolution

The life cycle of the Australian painted lady lasts around 53 days in the summer. The females lay eggs in the centre of the leaf of food plants. The eggs are green and hatch in about three days. As a caterpillar, the Australian painted lady is only active at night, during which its main activity is feeding. During the day, it hides in a curled leaf or at the foot of a food plant. The pupa hangs vertically from the underside of the leaf of a food plant, and the duration of the pupal stage is about two weeks.