The accompanying photo shows a moth in a short-term condition not often witnessed. The moth is newly-emerged from pupation, with its wings not yet expanded. At first glance, it could easily be assumed to be deformed.
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It is a female Boisduval's autumn moth. She retains this appearance for only an hour or so.
The moth was first noticed crawling along the ground, before making its way a short distance up a tree trunk. The comparative safety of the tree trunk offered a place to rest while blood pumped into the wings to expand them so that normal flight might occur.
Full-sized wings would require a much larger cocoon, so the wings of the moth - like those of most winged insects - unfold and expand after emergence.
The wings would eventually reach the tip of the striped abdomen, with the black lengthwise stripe continuing to the tip as well. The wingspan will then be about 50mm.
The male Boisduval's autumn moth is mostly dull brown, so is very different in appearance from the more striking white-winged female.
The caterpillars feed on gum leaves, and pupation probably occurs in leaf litter on the ground.
In observations on another Australian moth, observers have noticed that an emperor gum moth needs to emerge from its cocoon unaided. The extended cutting process and struggle through the hole helps the insect to gain proper strength and wing formation. If assisted out of its cocoon by well-meaning humans, the moth is often unable to properly expand its wings and is deformed for its short adult life.
The emperor gum moth clings to a safe place on a tree as soon as it emerges, so that its wings can expand. The autumn moth in the photo is more vulnerable, having to crawl up to a safer spot after it has come from the ground.
Today's photo comes from bushland near Talbot.
STARRY STARLINGS
Most birds gain a new set of feathers prior to winter. The starling is no exception.
Starlings are now in their handsome new plumage, with white tips to their new feathers. These white tips are the "stars" that give the starling its name.
As the year progresses, the white spots gradually wear off, and by breeding time in spring, most of the spotted plumage has gone, leaving the starling basically black, with a strong green and purple sheen.
The bill changes colour through the year too, being black now, but yellow in spring and summer.
Last year's young brown starlings have now gained their handsome starry plumage for the first time.
NATURE QUERIES ANSWERED
We have lots of millipedes outside and even in the house sometimes. Why do they come inside? What do they eat? S.L., Buninyong.
These are Portuguese millipedes, accidentally introduced to Australia from Europe. Millipedes wander around a lot at night, taking shelter in cooler places such as under mulch and leaves before sunrise. They eat all sorts of material they find on their wanderings, including rotting plant material, fallen fruit - almost anything moist. They are beneficial in the decomposition process.
They are said to be attracted to light at night, but they probably also wander inside looking for shelter. However, a normal house environment is too dry for them to survive and they do not breed inside. There are native millipedes in the Ballarat district, but they seem to be uncommon. Most have rougher bodies, unlike the smooth cylindrical body of the Portuguese millipede.