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Saturnia pyretorum

Saturnia pyretorum. Found flying just the other night...look for them now. Can you find one?

One of the largest caterpillars we have here in Hong Kong, and

often seen in great numbers, all together, in May. This species is

"univoltine" which means it has only one brood of offspring per

year.The eggs are generally laid in February and March, with

the caterpillars emerging after a couple of weeks (mid March to

early April). These feed voraciously and grow substantially until

May or early June, when they are easy to spot at night hanging

from leaves and plants. Pupation takes place in an intricately

camouflaged hard protective cocoon, often on a tree trunk or

railings or fences, like in LNEC. These are normally completed in

mid June and, amazingly, the insects stay inside until the following

January or February. It has been noted that this is an easy species

to rear and a great way to introduce kids to bugs and lifecycles of insects. The moth is equally

impressive with large eyespots, and not really sexually dimorphic except the females are larger.

SEE THEM Look for the colourful caterpillars around May, and the hard dried cocoons soon after.

Very good chances of finding them on large camphor trees or a large sweet gum tree. Most adults

are recorded from mid January through to the beginning of March.


The silk was used in the past to make into natural fish lines, and it has an artificial-

breeding history dating back to 885 AD.

A large proportion of the larvae of this species can contain parasitic wasps. The

caterpillars keep growing slowly, but they never make it to pupation, with the

wasps emerging in summer, leaving their friendly host larvae for dead.

The many varied common names make the ID of this moth quite confusing.

One of the 300 bugs in my book of bugs. to find out more go to the shop at . And here is a sample page about this moth


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